Journal articles on the topic 'Weeds Control Queensland'
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1
Pope, VA, and PN McConville. "Efficacy of post-emergence herbicides for weed control in chemical fallows in southern Queensland." Australian Journal of Experimental Agriculture 30, no. 1 (1990): 79. http://dx.doi.org/10.1071/ea9900079.
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Out-of-patent herbicides (2,4-D, MCPA, dichlorprop, amitrole, ametryn, atrazine and linuron) were screened at 3 rates of post-emergence application for weed control during fallow periods in southern Queensland. Herbicide efficacy was assessed on 26 weeds at 1 or more stages of growth. Each herbicide had a limited spectrum of activity over the range of species encountered, with amitrole being the most effective. The chlorophenoxy compounds controlled only some of the broad-leaved species and had no effect on grass species. Where more than 1 growth stage for each weed was encountered, differences in susceptibility to the herbicides were evident amongst stages. Most herbicides were ineffective on large weeds. The rate of herbicide application also influenced the level of activity on most species. Most of the weeds in the Brassicaceae group were susceptible to all rates of the chlorophenoxy herbicides.
2
Manalil, Sudheesh, Jeff Werth, Rod Jackson, Bhagirath Singh Chauhan, and Christopher Preston. "An assessment of weed flora 14 years after the introduction of glyphosate-tolerant cotton in Australia." Crop and Pasture Science 68, no. 8 (2017): 773. http://dx.doi.org/10.1071/cp17116.
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Glyphosate-tolerant (GT) cotton offers a multitude of benefits such as broad-spectrum and cost-effective weed control, simple weed management, and reduced impact on the environment. However, high adoption rates of GT cotton have led to overreliance on glyphosate in weed management and have decreased the use of other herbicide options and non-chemical weed-management strategies, possibly leading to the emergence of many resistant weeds. Previous surveys in 2006 and 2011 in the cotton-growing regions of New South Wales (NSW) and Queensland, Australia, indicated changes in weed populations over the period and increased prevalence of several weeds. These two surveys indicated increased dominance of Conyza bonariensis, Echinochloa colona, and Chloris virgata in these regions. Periodic weed surveys are necessary to assess weed population dynamics and shifts due to overreliance on glyphosate for weed management. A survey was carried out in the cotton-growing regions of NSW and Queensland in 2014–15, covering 135 fields. Survey results indicated the emergence of volunteer GT cotton as the most common weed present across all of the cotton-growing regions, occurring in 85% of fields, followed by E. colona (67% of fields surveyed), and C. bonariensis and Sonchus oleraceus, which were present in 51% of fields. The most prevalent grass weed after E. colona was C. virgata (37%). Broadleaf weeds Ipomoea lonchophylla and Amaranthus mitchellii were present in 40% and 37% of fields, respectively. Regional-level analysis indicated greater prevalence of Sesbania cannabina and Parthenium hysterophorus in Emerald region of Queensland. Lolium rigidum was present in the Griffith and Warren area of NSW during summer, even though it is a winter weed. The results of this study indicate integration of diversified weed-management options and inclusion of both non-chemical and chemical options because many major weeds observed in this study are tolerant to glyphosate and have already evolved resistance to glyphosate.
3
Page, M., RJS Beeton, and JJ Mott. "Grass response to shrub removal in two semi-arid vegetation communities." Rangeland Journal 22, no. 2 (2000): 220. http://dx.doi.org/10.1071/rj0000220.
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The control of woody weeds in the mulga lands of south-west Queensland is commonly regarded as essential for restoration of degraded systems. However, these shrubs have become a dominant and stable component of many mulga land ecosystems, and their removal may have unknown ecosystem impacts. This paper reports an experiment to determine the effect of woody weeds and grazing pressure on grass recruitment, cover and diversity in two vegetation communities in Queensland's mulga lands. Both factors influence grass recruitment, cover and diversity, but the response differs between the two vegetation communities investigated. The overall grass cover is consistently greater in sites where woody weeds were removed, and where grazing pressure was lowest. However, in the Dunefields community the cover and frequency of grass plants responded more to the removal of woody weeds than in the Mulga Sandplain community. In contrast, in the Mulga Sandplain community the grasses responded more to reducing or removing grazing pressure. Results suggest that subtle differences between systems influence grass dynamics, highlighting the need for community-specific research and management. Key words: shrub removal, semi-arid vegetation, vegetation communities, woody weeds
4
Bortolussi, G., J. G. McIvor, J. J. Hodgkinson, S. G. Coffey, and C. R. Holmes. "The northern Australian beef industry, a snapshot. 4. Condition and management of natural resources." Australian Journal of Experimental Agriculture 45, no. 9 (2005): 1109. http://dx.doi.org/10.1071/ea03262.
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Natural resource management practices were surveyed on 375 northern Australian beef properties in 8 regions during 1996–97. These producers represented a broad cross section of the beef industry in terms of geographical location, size of enterprise, and herd and ownership structures. More than 48% of producers reported land degradation (erosion, salinity, weeds, etc.) and >68% reported woody weeds on their properties. Eucalypt (Eucalyptus and Corymbia spp.) and wattle (Acacia spp.) regrowth were universally common native woody weeds. Parkinsonia (Parkinsonia aculeata) was widespread across all survey regions occurring with the greatest frequency in northern regions. A range of native and exotic woody weed species were regionally significant. Brigalow (Acacia harpophylla) regrowth was mainly reported in the central Queensland and Maranoa South West regions. Prickly acacia (Acacia nilotica) was mainly reported in central and north-west Queensland. Rubber vine (Cryptostegia grandiflora) was mainly reported in northern Queensland with a significant presence in central coastal and north-west Queensland. Infestations with multiple weed species were common. Although many producers reported the presence of problem woody weeds, only 3–29% indicated that weed management was practised. Most producers (67–100%) used fire. The intended purpose of fire varied across survey regions but fire was commonly used to reduce rank material, reduce fire risk, control woody weeds and for grazing management. Seasonal conditions and variability restricted fire use. Assessment by visual observation was a commonly used practice for determining stocking rate. Between 4–20% of producers were using visual observation combined with some form of calculation of stocking rate at the end of the growing season to determine stocking rate. A majority (>67%) of producers used some form of paddock spelling or regeneration practice. Many producers (47–89%) considered that they used conservative stocking rates. Carrying sufficient stock to meet income requirements was significantly (P<0.05) correlated with the percentage of producers reporting woody weeds as a problem on their property. In the 5 years preceding the survey, >66% of producers had increased the number of stock watering points, and more than 85% of producers had erected fencing. Most fencing was for new paddocks and laneways, or to replace old fences, and was not associated with new stock watering points. However, the installation of new stock watering points was associated with the creation of new paddocks. Planned future fencing focused on creating new paddocks or laneways or replacing old fences. The results are discussed in relation to contemporary natural resource management issues and the future approaches to and challenges of implementing sustainable rangeland management.
5
Walker, S. R., I. N. Taylor, G. Milne, V. A. Osten, Z. Hoque, and R. J. Farquharson. "A survey of management and economic impact of weeds in dryland cotton cropping systems of subtropical Australia." Australian Journal of Experimental Agriculture 45, no. 1 (2005): 79. http://dx.doi.org/10.1071/ea03189.
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In dryland cotton cropping systems, the main weeds and effectiveness of management practices were identified, and the economic impact of weeds was estimated using information collected in a postal and a field survey of Southern Queensland and northern New South Wales. Forty-eight completed questionnaires were returned, and 32 paddocks were monitored in early and late summer for weed species and density. The main problem weeds were bladder ketmia (Hibiscus trionum), common sowthistle (Sonchus oleraceus), barnyard grasses (Echinochloa spp.), liverseed grass (Urochloa panicoides) and black bindweed (Fallopia convolvulus), but the relative importance of these differed with crops, fallows and crop rotations. The weed flora was diverse with 54 genera identified in the field survey. Control of weed growth in rotational crops and fallows depended largely on herbicides, particularly glyphosate in fallow and atrazine in sorghum, although effective control was not consistently achieved. Weed control in dryland cotton involved numerous combinations of selective herbicides, several non-selective herbicides, inter-row cultivation and some manual chipping. Despite this, residual weeds were found at 38–59% of initial densities in about 3-quarters of the survey paddocks. The on-farm financial costs of weeds ranged from $148 to 224/ha.year depending on the rotation, resulting in an estimated annual economic cost of $19.6 million. The approach of managing weed populations across the whole cropping system needs wider adoption to reduce the weed pressure in dryland cotton and the economic impact of weeds in the long term. Strategies that optimise herbicide performance and minimise return of weed seed to the soil are needed. Data from the surveys provide direction for research to improve weed management in this cropping system. The economic framework provides a valuable measure of evaluating likely future returns from technologies or weed management improvements.
6
Vitelli, J. S., and B. A. Madigan. "Evaluation of a hand-held burner for the control of woody weeds by flaming." Australian Journal of Experimental Agriculture 44, no. 1 (2004): 75. http://dx.doi.org/10.1071/ea02096.
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A hand-held burner (Atarus Ranger) was evaluated as a method for controlling woody weeds by flaming in sensitive or riparian areas where traditional methods, such as chemical or mechanical control, have limited usefulness. The equipment was trialled on 3 North Queensland weed species: bellyache bush (Jatropha gossypiifolia), parkinsonia (Parkinsonia aculeata) and rubber vine (Cryptostegia grandiflora), at 5 different heat durations (0, 10, 30, 60 and 120 s) and on 3 plant size classes based on basal diameter (15–25, >25–50 and >50 mm).No significant difference in percentage mortality was recorded between a 10 s treatment and longer heat treatments for bellyache bush and parkinsonia plants, or between a 60 s treatment and longer heat treatments for rubber vine. A 10 s treatment killed 92% of the treated bellyache bush plants and 83% of the parkinsonia plants, while a 60 s treatment killed 76% of the treated rubber vine plants (values are the means of all size classes combined).Flaming was least effective on rubber vine, which had the thickest bark, but was highly effective on bellyache bush, which had the highest bark moisture content. Weeds with a low capacity for root suckering, thin bark, high bark moisture content and low bark density appear the best candidates for flaming. Flaming is an effective technique for the control of woody weeds with efficacy varying among species. Individual plants are targeted, and the technique is accepted by organic farming groups.
7
Spennemann, D. H. R., and L. R. Allen. "Feral olives ( Olea europaea) as future woody weeds in Australia: a review." Australian Journal of Experimental Agriculture 40, no. 6 (2000): 889. http://dx.doi.org/10.1071/ea98141.
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Olives (Olea europaea ssp. europaea), dispersed from 19th century orchards in the Adelaide area, have become established in remnant bushland as a major environmental weed. Recent expansion of the Australian olive industry has resulted in the widespread planting of olive orchards in South Australia, Victoria, New South Wales, Western Australia, Queensland and parts of Tasmania. This paper reviews the literature on the activity of vertebrate (principally avian) olive predators and their potential as vectors for spreading this plant into Australian remnant bushland. The effects of feralisation on the olive plant, which enhances its capacity for dispersal as a weed, place wider areas of south-eastern Australia at risk. A number of approaches for the control of olives as woody weeds are addressed. Proponents of new agricultural crops have moral and environmental obligations to assess the weed potential of these crops.
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Rasool, Ghulam, Gulshan Mahajan, Rajpaul Yadav, Zarka Hanif, and Bhagirath Singh Chauhan. "Row spacing is more important than seeding rate for increasing Rhodes grass (Chloris gayana) control and grain yield in soybean (Glycine max)." Crop and Pasture Science 68, no. 7 (2017): 620. http://dx.doi.org/10.1071/cp17229.
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In Australia, soybean (Glycine max (L.) Merr.) is planted at a low density in wide rows, and weeds substantially reduce yield because of opportunities for their growth in the wide rows. Field studies were conducted over 2 years at the University of Queensland farm, Gatton, Australia, to assess the effect of row spacing and seeding rate on the competitiveness of soybeans with a model weed, Rhodes grass (Chloris gayana Kunth). The experiment was conducted in a split-split plot design, replicated three times. Main plots comprised two seeding rates (40 and 80 kg ha–1), subplots two row spacings (25 and 75 cm), and sub-subplots four Rhodes grass infestation periods (weedy from planting to maturity, weedy from 3 weeks after planting (WAP) to maturity, weedy from 6 WAP to maturity, and weed-free from planting to maturity). The results showed that seed rate did not influence Rhodes grass biomass or soybean yield. Soybean yield was greater and Rhodes grass biomass was less in the 25-cm rows than the 75-cm rows. For the 25-cm rows, Rhodes grass biomass in the plots infested beyond 3 WAP was 81–89% less than in the season-long weedy plots, whereas for the wider row crop, this reduction was only 60–75%. For the 25-cm rows, soybean yield in the plots infested with Rhodes grass beyond 3 WAP was 30–36% less than under weed-free condition. However, for the 75-cm rows, this reduction was 56–65%. The results suggest that planting soybean in wider rows caused greater reduction in yield and required an earlier weed management program than planting in narrow rows. The study also suggested that narrowing row spacing was more important than increasing seeding rates for improving weed control and soybean grain yield.
9
Felton, WL, GA Wicks, and SM Welsby. "A survey of fallow practices and weed floras in wheat stubble and grain sorghum in northern New South Wales." Australian Journal of Experimental Agriculture 34, no. 2 (1994): 229. http://dx.doi.org/10.1071/ea9940229.
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A survey undertaken in northern New South Wales after the 1989 wheat harvest investigated the effects of cultural practices used by dryland farmers on summer weed flora. Only 50% of fallow paddocks surveyed between December and February were weedfree, and by mid January 65% had inadequate stubble cover (<1000 kg/ha) for protection from soil erosion, mainly because of excessive tillage. By February, only 10% of paddocks were being sprayed with a herbicide to control weeds. Examination of 65 uncultivated fallow wheat stubble paddocks and 25 grain sorghum crops identified 87 and 51 different weed species, respectively. In fallow paddocks where no herbicide had been used, 69 and 61 species were found in ungrazed and grazed paddocks, respectively. Where glyphosate had been used the number of species was 37 (grazed) and 39 (ungrazed), and for glyphosate plus atrazine, 23 and 18 species. The number of weed species found in grain sorghum was 29 for cultivated without atrazine, 35 for cultivated with atrazine, and 35 for no-tillage with atrazine, The most important weeds found in fallow were liverseed grass, native millet, common sowthistle, wireweed, and barnyard grasses. Black bindweed was a problem where atrazine had not been used. Native millet was the most abundant species where atrazine had been applied. In grain sorghum the most common broadleaf weeds for cultivated paddocks with no atrazine treatment were Tribulus spp., Australian bindweed, pigweed, and Bathurst burr, while the most common grass weeds were barnyard grasses, liverseed grass, stinkgrass, and native millet. When cultivation plus atrazine was used, barnyard grasses, native millet, wild oats, and liverseed grass were the most common weeds. In minimum tillage or no-tillage paddocks treated with atrazine, native millet, Queensland blue grass, liverseed grass, common sowthistle, Australian bindweed, and windmill grass were the most common weeds.
10
Calvert, Brendan, Alex Olsen, James Whinney, and Mostafa Rahimi Azghadi. "Robotic Spot Spraying of Harrisia Cactus (Harrisia martinii) in Grazing Pastures of the Australian Rangelands." Plants 10, no. 10 (September 29, 2021): 2054. http://dx.doi.org/10.3390/plants10102054.
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Harrisia cactus, Harrisia martinii, is a serious weed affecting hundreds of thousands of hectares of native pasture in the Australian rangelands. Despite the landmark success of past biological control agents for the invasive weed and significant investment in its eradication by the Queensland Government (roughly $156M since 1960), it still takes hold in the cooler rangeland environments of northern New South Wales and southern Queensland. In the past decade, landholders with large infestations in these locations have spent approximately $20,000 to $30,000 per annum on herbicide control measures to reduce the impact of the weed on their grazing operations. Current chemical control requires manual hand spot spraying with high quantities of herbicide for foliar application. These methods are labour intensive and costly, and in some cases inhibit landholders from performing control at all. Robotic spot spraying offers a potential solution to these issues, but existing solutions are not suitable for the rangeland environment. This work presents the methods and results of an in situ field trial of a novel robotic spot spraying solution, AutoWeed, for treating harrisia cactus that (1) more than halves the operation time, (2) can reduce herbicide usage by up to 54% and (3) can reduce the cost of herbicide by up to $18.15 per ha compared to the existing hand spraying approach. The AutoWeed spot spraying system used the MobileNetV2 deep learning architecture to perform real time spot spraying of harrisia cactus with 97.2% average recall accuracy and weed knockdown efficacy of up to 96%. Experimental trials showed that the AutoWeed spot sprayer achieved the same level of knockdown of harrisia cactus as traditional hand spraying in low, medium and high density infestations. This work represents a significant step forward for spot spraying of weeds in the Australian rangelands that will reduce labour and herbicide costs for landholders as the technology sees more uptake in the future.
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Davidson, Bill, Tony Cook, and Bhagirath S. Chauhan. "Alternative Options to Glyphosate for Control of Large Echinochloa colona and Chloris virgata Plants in Cropping Fallows." Plants 8, no. 8 (July 24, 2019): 245. http://dx.doi.org/10.3390/plants8080245.
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The over-reliance on the herbicide glyphosate for knockdown weed control in fallows under minimum and zero-till cropping systems has led to an increase in populations of glyphosate-resistant weeds. Echinochloa colona and Chloris virgata are two major grass weeds in the cropping regions of northern New South Wales and southern Queensland, Australia, that have become harder to kill due to a steady rise in the occurrence of glyphosate-resistant weed populations. Therefore, to help growers contain these hard to kill fallow weeds, an alternate approach to glyphosate application is needed. With this purpose in mind, a pot study was carried out during the summer seasons of 2015 and 2016 at the Tamworth Agricultural Institute, Tamworth, NSW, Australia, to evaluate the efficacy of tank mixtures and sequential applications of Group H (4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor), Group C (inhibitors of photosynthesis at photosystem II), Group A (ACCase inhibitors) and Group L (photosystem I inhibitor) herbicides on late tillering E. colona and C. virgata plants. These herbicide groups are a global classification by the Herbicide Resistance Action Committee. Highly effective results were achieved in this study using combinations of Groups H, C, A and L herbicides applied as tank mixtures for controlling large E. colona plants. Additionally, sequential applications of Group H, C and A herbicides followed by (fb) paraquat were shown to be very effective on large E. colona plants. Late tillering C. virgata plants were generally well controlled by tank mixtures, and sequential applications proved to be highly effective on this grass weed as well. Haloxyfop in combination with paraquat as a tank mixture, via sequential application or as a stand-alone treatment, was highly effective for C. virgata control; however, using combinations of herbicide groups is the preferred choice when combating herbicide resistant weed populations. There was a clear synergy shown using Group H, Group C and Group A herbicides in combination with the Group L herbicide paraquat in this study for controlling advanced E. colona and C. virgata plants. These combinations were shown to be successful on plants grown under glasshouse conditions; however; these treatments would need to be tested on plants grown in a field situation to show whether they will be a useful solution for farmers who are trying to control these weeds in fallow.
12
Walker, SR, WH Hazard, AF Mich, and BA Silver. "Effect of herbicides on black pigweed and sesbania pea, and yields of five grain sorghum cultivars in central Queensland." Australian Journal of Experimental Agriculture 28, no. 3 (1988): 327. http://dx.doi.org/10.1071/ea9880327.
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Six experiments were conducted in central Queensland to compare the efficacy of some post-emergence herbicides and mixtures in controlling black pigweed (Trianthema portulacastrum) and sesbania pea (Sesbania cannabina). The herbicides tested were atrazine, 2,4-D, dicamba, picloram plus 2,4-D, and fluroxypyr and mixtures of atrazine with 2,4-D, dicamba, picloram plus 2,4-D, fluroxypyr or tridiphane. In addition, 4 experiments were conducted to assess the tolerance of 5 sorghum cultivars (Sorghum bicolor) to some of these individual herbicides and atrazine mixtures. Small black pigweed and sesbania pea (< 10 cm diameter) were controlled with atrazine at 1.0 kg a.i./ ha, while for larger black pigweed (up to 15 cm diameter) atrazine at 2.25 kg/ha and atrazine mixtures were effective and for sesbania pea (up to 12 cm high) atrazine at 2.25 kg/ha, picloram plus 2,4-D at 35 + 140 g a.i./ha, fluroxypyr at 0.3 kg a.i./ha and atrazine mixtures were effective. In general, control of both weeds by mixtures with atrazine at 1.0 kg/ha was as effective as atrazine at 2.25 kg/ha alone. In the tolerance experiments the treatments were applied at 18-20 days after planting when the number of sorghum leaves was 4-6. Spraying with 2,4-D, dicamba, MCPA, picloram plus 2,4-D and atrazine mixtures with 2,4-D, dicamba and picloram plus 2,4-D consistently caused injury symptoms, delayed flowering and sometimes reduced grain yield. However, the susceptibility of sorghum to these treatments varied with seasons and cultivars. Overall, yield reductions were less when 2,4-D, dicamba and MCPA were applied at lower rates in the atrazine mixtures than when applied alone. All sorghum cultivars were tolerant of atrazine at 4.5 kg/ha. For effective control of both weeds, for crop safety and for minimum atrazine residues after harvest, we recommend that the weeds black pigweed and sesbania pea be sprayed when less than 10 cm in diameter or height, respectively, with atrazine at 1.0 kg/ha.
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Crawford, M. H., V. Rincon-Florez, A. Balzer, Y. P. Dang, L. C. Carvalhais, H. Liu, and P. M. Schenk. "Changes in the soil quality attributes of continuous no-till farming systems following a strategic tillage." Soil Research 53, no. 3 (2015): 263. http://dx.doi.org/10.1071/sr14216.
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The adoption of no-till farming systems has greatly reduced energy and machinery inputs while significantly improving soil health and productivity. However, the control of crop weeds and diseases in no-till (NT) systems has become increasingly difficult for landholders in Australia’s northern grains regions, with occasional strategic tillage (ST) being considered as a potential management option. This study investigated the effects of occasional ST on physical, chemical and biological soil properties, productivity, and weed control on five long-term (7–44 years) NT-managed soils. The study area extended from Biloela (Vertosol, 666 mm annual rainfall), Condamine (Sodosol, 624 mm annual rainfall), Moonie (Dermosol, 636 mm annual rainfall) and Warwick (Vertosol, 675 mm annual rainfall) in Queensland to Wee Waa (Vertosol, 582 mm annual rainfall) in New South Wales. Tillage treatments included chisel, offset disc and prickle–disc chain with various timings and frequencies. Soil samples (0–0.3 m) obtained 3 and 12 months after occasional ST were analysed for total and particulate organic carbon (TOC, POC), available phosphorus (P), bulk density, soil water, and microbial enzymatic activity. In-crop weed density was also recorded. One-time tillage, with chisel tines, offset disc or chain harrows, in long-term NT helped to control winter weeds in the first year, with variable results in the second year. Grain yield overall showed no significant impact in either year, except on the Brown Sodosol (P = 0.08) in the first year. The initial impacts of strategic tillage on soil water were largely restricted to the 0–0.1 m depth range, with slight, non-significant decreases occurring. Available P, TOC, POC and total microbial enzymatic activity were not significantly impacted by either cultivation frequency or implement type. The use of an occasional ST for the purpose of weed control could be utilised as a viable management option for NT systems in the region without impacting on long-term productivity.
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Henderson, CWL, and MJ Webber. "Phytotoxicity to transplanted lettuce (Lactuca sativa) of three pre-emergence herbicides: metolachlor, pendimethalin, and propachlor." Australian Journal of Experimental Agriculture 33, no. 3 (1993): 373. http://dx.doi.org/10.1071/ea9930373.
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The phytotoxicity of the pre-emergence herbicides metolachlor, pendimethalin, and propachlor to heading lettuce was investigated in 5 experiments conducted in southern Queensland during 1990-91. Metolachlor was applied before transplanting lettuce seedlings in 2 experiments. On a krasnozem soil at Toowoomba, spraying >1.75 kg a.i./ha reduced lettuce growth and the number of marketable lettuce heads. When applied on a black earth at Gatton, 1.44 kg a.i./ha stunted the lettuce and reduced the number of marketable heads by 30% compared with hand-weeded treatments. On both soils, 2.2-2.9 kg a.i./ha of metolachlor is recommended for broadleaf weed control in other crops. The risks of phytotoxicity from such rates preclude its use in transplanted lettuce in this environment. Lettuce were severely stunted from application of 1 kg a.i./ha of pendimethalin after transplanting. Spraying at the same rate before transplanting initially reduced lettuce width in 1 of 4 experiments, but the lettuce recovered. Lettuce yields from areas treated with 1 kg a.i./ha before transplanting were unaffected. The number and size of harvested heads tended to decline where >1.3 kg a.i./ha was applied. Higher rates (up to 1.5 kg a.i./ha) may be acceptable on krasnozem soils. Use of pendimethalin at 1-1.3 kg a.i./ha would control or suppress many important broadleaf weeds in lettuce, as well as a range of grasses. Propachlor was less phytotoxic when applied immediately after transplanting the lettuce seedlings than when sprayed before transplanting. Yields were unaffected from application of 2-2.5 kg a.i./ha after transplanting on black earth and sandy soils. When sprayed before transplanting, >2 kg a.i./ha caused significant yield reductions in several experiments, although lettuce grown on a krasnozem soil appeared more tolerant. Use of 2 kg a.i./ha of propachlor would give a suppressive effect against several broadleaf weeds, but another herbicide would also be required to achieve effective weed control. A spraying strategy involving pendimethalin and propachlor herbicides in transplanted lettuce has the potential to reduce weed control costs by up to 80%.
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Khan, Asad M., Ahmadreza Mobli, Jeff A. Werth, and Bhagirath S. Chauhan. "Effect of emergence time on growth and fecundity of redroot pigweed (Amaranthus retroflexus) and slender amaranth (Amaranthus viridis): emerging problem weeds in Australian summer crops." Weed Science 69, no. 3 (February 1, 2021): 333–40. http://dx.doi.org/10.1017/wsc.2021.9.
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AbstractRedroot pigweed (Amaranthus retroflexus L.) and slender amaranth (Amaranthus viridis L.) are considered emerging problematic weeds in summer crops in Australia. An outdoor pot experiment was conducted to examine the effects of planting time on two populations of A. retroflexus and A. viridis at the research farm of the University of Queensland, Australia. Both species were planted every month from October to January (2017 to 2018 and 2018 to 2019), and their growth and seed production were recorded. Although both weeds matured at a similar number of growing degree days (GDD), they required a different number of days to complete their life cycles depending on planting date. The growth period was reduced and flowering occurred sooner as both species experienced cooler temperatures and shorter daylight hours. Both species exhibited increased height, biomass, and seed production for the October-sown plants compared with other planting times, and these parameters were reduced by delaying the planting time. The shoot and root biomass of A. retroflexus and A. viridis (averaged over both populations) was reduced by more than 70% and 65%, respectively, when planted in January, in comparison to planting in October. When planted in October, A. retroflexus and A. viridis produced 11,350 and 5,780 seeds plant−1, but these were reduced to 770 and 365 seeds plant−1 for the January planting date, respectively. Although the growth and fecundity of these species were dependent on planting time, these weeds could emerge throughout the late spring to summer growing season (October to March) in southeast Australia and could produce a significant number of seeds. The results showed that when these species emerged in the late spring (October), they grew vigorously and produced more biomass in comparison with the other planting dates. Therefore, any early weed management practice for these species could be beneficial for minimizing the subsequent cost and energy inputs toward their control.
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Mobli, Ahmadreza, Amar Matloob, and Bhagirath Singh Chauhan. "Glyphosate-induced hormesis: impact on seedling growth and reproductive potential of common sowthistle (Sonchus oleraceus)." Weed Science 68, no. 6 (October 12, 2020): 605–11. http://dx.doi.org/10.1017/wsc.2020.77.
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AbstractIn Australia, glyphosate is widely used in glyphosate-tolerant crops and fallows to control weeds such as common sowthistle (Sonchus oleraceus L.). It has been hypothesized that glyphosate at sublethal doses, as a consequence of herbicide drift, may have a stimulatory effect on S. oleraceus growth. In 2017, pot trials were conducted to evaluate the effect of low doses of glyphosate on growth and seed production of this weed at the Weed Science Screenhouse Facility at the University of Queensland, Australia. At the 4- to 5-leaf stage (3-wk-old rosette), plants were treated with low doses of glyphosate (0 [control], 5, 10, 20, 40, 80, and 800 g ae ha−1), and their responses were recorded until plant maturity. The study was repeated after completion of the first experimental run. An additional glyphosate dose (2.5 g ha−1) was added in the second run. The low doses of glyphosate (<40 g ha−1) caused a significant increase in S. oleraceus plant height and number of leaves compared with the no-glyphosate treatment. The highest stimulatory effect was observed at 5 g ha−1. At 5 g ha−1 glyphosate, S. oleraceus seed production increased by 154% and 101% in the first and second experimental runs, respectively, compared with the no-glyphosate treatment. The results of this study suggest that the sublethal doses of glyphosate produced hormetic effects on growth and seed production of S. oleraceus that changed the dynamics of weed–crop competition.
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Salgotra, Romesh, and Bhagirath Singh Chauhan. "The First Report of Target-Site Resistance to Glyphosate in Sweet Summer Grass (Moorochloa eruciformis)." Plants 10, no. 9 (September 11, 2021): 1885. http://dx.doi.org/10.3390/plants10091885.
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Sweet summer grass is a problematic weed in the central Queensland region of Australia. This study found glyphosate resistance in two biotypes (R1 and R2) of sweet summer grass. The level of resistance in these biotypes was greater than 8-fold. The glyphosate dose required to reduce dry matter by 50% (GR50) for the resistant populations varied from 1993 to 2100 g ha−1. A novel glyphosate resistance double point mutation in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene was identified for the first time in sweet summer grass. Multiple mutations, including multiple amino acid changes at the glyphosate target site, as well as mutations involving two nucleotide changes at a single amino acid codon, were observed. Both resistant biotypes exhibited a nucleotide change of CAA to ACA in codon 106, which predicts an amino acid change of proline to a threonine (Pro-106-Thr). In addition, the R1 biotype also possessed a mutation at codon 100, where a nucleotide substitution of T for G occurred (GCT to TCT), resulting in a substitution of serine for alanine (Ala-100-Ser). Understanding the molecular mechanism of glyphosate resistance will help to design effective management strategies to control invasive weeds.
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Landsberg, RG, AJ Ash, RK Shepherd, and GM Mckeon. "Learning From History to Survive in the Future: Management Evolution on Trafalgar Station, North-East Queensland." Rangeland Journal 20, no. 1 (1998): 104. http://dx.doi.org/10.1071/rj9980104.
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Managing rangeland enterprises requires balancing socio-economic goals within a production environment characterised by ecological complexity and large climatic variability. Trafalgar Station in north-east Queensland, has been trying to maintain this balance over a period of 80 years and three generations of the one family. This paper explores how management on Trafalgar Station has gone through four evolutionary phases and examines the advantages and disadvantages of each of these stages of development. The first 50 years of management was a technologically constrained era of low stock numbers and poor productivity but there were few resource management problems. Next followed a 20 year period of production maximisation which was made possible by improved cattle genetics and nutritional technologies. With drought feeding occurring more frequently and loss of perennial grasses and soil becoming more evident, there came the realisation that this high stocking strategy was unsustainable. The management of Trafalgar then embarked on a new philosophy based on conservative stocking (similar to historical levels) and increased emphasis on herd, pasture and financial management. This new management philosophy required a transitional phase where stock numbers. and income, were very low to allow pasture condition to improve. Current herd management focuses on maintaining quality rather than quantity, strategic use of supplements for production, and developing a diverse range of markets for sale cattle. Conservative stock numbers have increased opportunities in pasture management with 15 to 20% of the property now annually rested from grazing. Fire has been reintroduced to restrict "thickening" of native woody plants and to control exotic woody weeds. Together with long-term financial planning, these improvements in management are reducing economic risk. The perceived benefits of the current management philosophy are supported by simulation modelling studies of pasture and animal production and analyses of property economics.
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Sequeira, R. V., A. Shields, A. Moore, and P. De Barro. "Inter-seasonal population dynamics and pest status of Bemisia tabaci (Gennadius) biotype B in an Australian cropping system." Bulletin of Entomological Research 99, no. 4 (December 9, 2008): 325–35. http://dx.doi.org/10.1017/s000748530800638x.
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AbstractBemisia tabaci, biotype B, commonly known as the silverleaf whitefly (SLW) is an alien species that invaded Australia in the mid-90s. This paper reports on the invasion ecology of SLW and the factors that are likely to have contributed to the first outbreak of this major pest in an Australian cotton cropping system. Population dynamics of SLW within whitefly-susceptible crop (cotton and cucurbit) and non-crop vegetation (sowthistle, Sonchus spp.) components of the cropping system were investigated over four consecutive growing seasons (September–June) 2001/02–2004/05 in the Emerald Irrigation Area (EIA) of Queensland, Australia. Based on fixed geo-referenced sampling sites, variation in spatial and temporal abundance of SLW within each system component was quantified to provide baseline data for the development of ecologically sustainable pest management strategies. Parasitism of large (3rd and 4th instars) SLW nymphs by native aphelinid wasps was quantified to determine the potential for natural control of SLW populations. Following the initial outbreak in 2001/02, SLW abundance declined and stabilised over the next three seasons. The population dynamics of SLW is characterised by inter-seasonal population cycling between the non-crop (weed) and cotton components of the EIA cropping system. Cotton was the largest sink for and source of SLW during the study period. Over-wintering populations dispersed from weed host plant sources to cotton in spring followed by a reverse dispersal in late summer and autumn to broad-leaved crops and weeds. A basic spatial source-sink analysis showed that SLW adult and nymph densities were higher in cotton fields that were closer to over-wintering weed sources throughout spring than in fields that were further away. Cucurbit fields were not significant sources of SLW and did not appear to contribute significantly to the regional population dynamics of the pest. Substantial parasitism of nymphal stages throughout the study period indicates that native parasitoid species and other natural enemies are important sources of SLW mortality in Australian cotton production systems. Weather conditions and use of broad-spectrum insecticides for pest control are implicated in the initial outbreak and on-going pest status of SLW in the region.
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Reid, Nick, and Simon F. Shamoun. "Contrasting research approaches to managing mistletoes in commercial forests and wooded pasturesThis minireview is one of a collection of papers based on a presentation from the Stem and Shoot Fungal Pathogens and Parasitic Plants: the Values of Biological Diversity session of the XXII International Union of Forestry Research Organization World Congress meeting held in Brisbane, Queensland, Australia, in 2005." Botany 87, no. 1 (January 2009): 1–9. http://dx.doi.org/10.1139/b08-109.
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Many mistletoe species are pests in agricultural and forest ecosystems throughout the world. Mistletoes are unusual “weeds” as they are generally endemic to areas where they achieve pest status and, therefore, classical biological control and broad-scale herbicidal control are usually impractical. In North American coniferous forests, dwarf mistletoe ( Arceuthobium spp.) infection results in major commercial losses and poses a public liability in recreation settings. Hyperparasitic fungi have potential as biological control agents of dwarf mistletoe, including species which attack shoots, berries, and the endophytic systems of dwarf mistletoe. Development of an inundative biological control strategy will be useful in situations where traditional silvicultural control is impractical or undesirable. In southern Australia, farm eucalypts are often attacked and killed by mistletoes ( Amyema spp.) in grazed landscapes where tree decline and biodiversity loss are major forms of land degradation. Although long-term strategies to achieve a balance between mistletoe and host abundance are promoted, many graziers want short-term options to treat severely infected trees. Recent research has revisited the efficiency and efficacy of silvicultural treatments and selective herbicides in appropriate situations. The results of recent research on these diverse management strategies in North America and Australia are summarized.
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Radford, BJ, AJ Key, LN Robertson, and GA Thomas. "Conservation tillage increases in soil water storage, soil animal populations, grain yield, and response to fertiliser in the semi-arid subtropics." Australian Journal of Experimental Agriculture 35, no. 2 (1995): 223. http://dx.doi.org/10.1071/ea9950223.
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We compared 4 tillage practices (traditional, stubble mulch, reduced, no tillage) during 10 years under rainfed conditions on an alluvial soil in the semi-arid subtropics of central Queensland. In the final 4 years, responses to applied fertiliser nitrogen (N), sulfur (S), and zinc (Zn) were determined. We measured soil water storage, soil nitrate accumulation, grain yield (sorghum, wheat), grain protein content, and populations of soil macrofauna, with the aim of identifying soil-conserving practices that also produce high yields of high quality grain. Stubble mulch, reduced tillage, and no tillage all outyielded traditional tillage when soil fertility was adequate. With applied N, S, and Zn, the mean wheat yields from traditional, stubble mulch, reduced, and no tillage were 2.44, 3.32, 3.46, and 3.64 t/ha, respectively. The yield responses to tillage practices were due to increases in storage of soil water or efficiency of crop water use or both. Populations of soil macrofauna averaged (per m2) 19 (traditional tillage), 21 (stubble mulch), 33 (reduced tillage), and 44 (no tillage). The effect of the tillage practices on soil animal populations may be a factor contributing to the measured differences in soil water storage and water use efficiency. We conclude that conservation tillage practices can greatly increase grain yields, provided crop and fallow management practices are appropriate. Potential yield advantages are realised if crop establishment, crop nutrition; and control of weeds, bests, and diseases ark adequate.
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Ireland, K. B., N. A. Haji Mohamad Noor, E. A. B. Aitken, S. Schmidt, and J. C. Volin. "First Report of Glomerella cingulata (Colletotrichum gloeosporioides) Causing Anthracnose and Tip Dieback of Lygodium microphyllum and L. japonicum in Australia." Plant Disease 92, no. 9 (September 2008): 1369. http://dx.doi.org/10.1094/pdis-92-9-1369a.
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The Old World climbing fern, Lygodium microphyllum (Cav.) R. Br., and Japanese climbing fern, L. japonicum (Thunb.) Sw., are invasive noxious weeds in Florida (1). Exploratory surveys for classical biological control agents of L. microphyllum in the fern's native range of Australia and Asia have focused on aboveground herbivores (1). From February to August 2006, fungi were isolated from symptomatic foliage, including lesions associated with leaf curls caused by the mite Flocarus perrepae Knihinicki & Boczek., obtained from L. microphyllum at sites across southeast Queensland, Australia and from both fern species grown at the CSIRO Long Pocket Laboratories in Brisbane, Australia. Anthracnose symptoms with chlorotic margins, initiating at the tip or base of the individual pinnules, were observed on fronds. Dieback symptoms affected growing tips, with sunken lesions and a gradual necrotic wilt as far as the next growth junction of pinnae. Sections from diseased margins were surface sterilized, placed onto water agar, and incubated at 23°C with a 16-h photoperiod. Variable colonies of white-to-gray mycelia, felted or tufted with complete margins, grew well on oatmeal agar and potato dextrose agar. Conidia were hyaline to light salmon, aseptate, straight, and cylindrical (10.4 to 18.2 × 2.6 to 5.2 μm), borne in salmon-to-bright orange masses at 25°C, and consistent with previous descriptions of Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. (3), anamorph of Glomerella cingulata (2). Asci that formed after 3 to 4 weeks in culture were eight-spored, clavate to cylindrical (46.8 to 62.4 × 9.1 to 11.7 μm), and thickened at the apex, and ascospores were cylindrical (11.7 to 18.2 × 3.9 to 5.2 μm), slightly curved, unicellular and hyaline, which is consistent with descriptions of G. cingulata (2). No fruiting bodies were observed in planta; acervuli, setae, and perethecia were not observed. Identification was further confirmed by molecular analysis using the primer pair ITS1/ITS4 (4) (GenBank Accession No. EU697014), indicating 100% similarity to isolates of G. cingulata. To confirm pathogenicity, Koch's postulates were performed on three plants of L. japonicum and 12 plants of L. microphyllum, with an equal number of controls. Conidial suspensions were made to 1.7 × 106 conidia ml–1. During the experiments in the glasshouse, temperatures ranged from 12.6 to 40°C and relative humidity from 39 to 85%. Tips and fronds were collected after 2 to 8 weeks and isolation and identification performed. G. cingulata was consistently reisolated from diseased tissue. No symptoms appeared on controls and isolations did not yield the pathogen. To our knowledge, this is the first report of G. cingulata infecting L. microphyllum and L. japonicum in Australia. Its potential as a biological control agent in the ferns' introduced range remains to be tested. References: (1) J. A. Goolsby et al. Biol. Control. 28:33, 2003. (2) J. E. M. Mordue. Glomerella cingulata. No. 315 in: CMI Descriptions of Pathogenic Fungi and Bacteria. CAB, Kew, UK, 1971. (3) B. C. Sutton. The Genus Glomerella and its Anamorph Colletotrichum. In: Colletotrichum: Biology, Pathology and Control. J. A. Bailey and M. J. Jeger, eds. CAB International, Wallingford, UK, 1992. (4) T. M. White et al. Amplification and Direct Sequencing of Fungal Ribosomal RNA for Phylogenetics. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.
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Mahajan, Gulshan, Kerry McKenzie, and Bhagirath S. Chauhan. "Influence of row spacing and cultivar selection on annual ryegrass (Lolium rigidum) control and grain yield in chickpea (Cicer arietinum)." Crop and Pasture Science 70, no. 2 (2019): 140. http://dx.doi.org/10.1071/cp18436.
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Annual ryegrass (ARG) (Lolium rigidum Gaudin) is a problematic weed for chickpea (Cicer arietinum L.) production in Australia. Understanding the critical period of control of ARG in chickpea is important for developing effective integrated management strategies to prevent unacceptable yield loss. Experiments were conducted over 2 years at the research farm of the University of Queensland, Gatton, to evaluate the effect of chickpea row spacing (25 and 75cm) and cultivar (PBA Seamer and PBA HatTrick) and ARG infestation period (from 0, 3 and 6 weeks after planting (WAP), and weed-free) on ARG suppression and grain yield of chickpea. Year×treatment interactions were not significant for any parameter, and none of the treatment combinations showed any interaction for grain yield. Average grain yield was greater (20%) with 25-cm than 75-cm rows. On average, PBA Seamer had 9% higher yield than PBA HatTrick. Average grain yield was lowest in season-long weedy plots (562kg ha–1) and highest in weed-free plots (1849kg ha–1). Grain yield losses were lower when ARG emerged at 3 WAP (1679kg ha–1). Late-emerged ARG (3 and 6 WAP) had lower biomass (4.7–22.2g m–2) and number of spikes (5–24m–2) than ARG that emerged early; at 0 WAP, weed biomass was 282–337g m–2 and number of spikes 89–120m–2. Compared with wide row spacing, narrow row spacing suppressed ARG biomass by 16% and 52% and reduced number of spikes of ARG by 26% and 48% at 0 WAP and 3 WAP, respectively. PBA Seamer suppressed ARG growth more effectively than PBA HatTrick, but only in the season-long weedy plots. Our results imply that in ARG-infested fields, grain yield of chickpea can be increased by exploring narrow row spacing and weed-competitive cultivars. These cultural tools could be useful for developing integrated weed management tactics in chickpea in combination with pre-emergent herbicides.
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Campbell, Shane, Wayne Vogler, Dannielle Brazier, Joseph Vitelli, and Simon Brooks. "Weed leucaena and its significance, implications and control." Tropical Grasslands-Forrajes Tropicales 7, no. 4 (September 3, 2019): 280–89. http://dx.doi.org/10.17138/tgft(7)280-289.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena (Leucaena leucocephala) is widely recognized in many countries as a commercially valuable plant, particularly when used as a nutritious fodder in subtropical and tropical regions. However, it is also considered an environmental weed in some countries due to its ability to form dense infestations in disturbed areas, where it is not proactively managed or grazed. These different perspectives have made leucaena a contentious species. Ideally, landholders and relevant jurisdictions in charge of invasive species need to work together to minimize its spread as a weed and manage existing infestations. To date, the response has been varied, ranging from no action through to some jurisdictions formally recognizing leucaena as an environmental weed within relevant legislation and applying requirements to minimize its impact. Between these extremes, there are initiatives such as an industry Code of Practice (i.e. The Leucaena Network in Australia), recommending that those growing leucaena adhere to certain principles and practices to minimize the risk of spread from their operations. The biology of weed leucaena (e.g. large seed production, relatively long-lived seed banks) and the situations in which it spreads (e.g. roadsides and riparian systems) pose management challenges to landholders and relevant jurisdictions. Adaptive management and experimental research are necessary to identify effective control strategies for a range of situations.
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Belgeri, Amalia, Ali Ahsan Bajwa, Asad Shabbir, Sheldon Navie, Gabrielle Vivian-Smith, and Steve Adkins. "Managing an Invasive Weed Species, Parthenium hysterophorus, with Suppressive Plant Species in Australian Grasslands." Plants 9, no. 11 (November 16, 2020): 1587. http://dx.doi.org/10.3390/plants9111587.
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Parthenium weed has been invading native and managed Australian grasslands for almost 40 years. This study quantified the potential of selected plant mixtures to suppress the growth of parthenium weed and followed their response to grazing and their impact upon plant community diversity. The first mixture consisted of predominantly introduced species including Rhodes grass, Bisset bluegrass, butterfly pea and green panic. This mixture produced biomass rapidly and showed tolerance to weed species other than parthenium weed. However, the mixture was unable to suppress the growth of parthenium weed. The second mixture of predominantly native pasture species (including forest bluegrass, Queensland bluegrass, Buffel grass and siratro) produced biomass relatively slowly, but eventually reached the same biomass production as the first mixture 12 weeks after planting. This mixture suppressed parthenium weed re-establishment by 78% compared to the control treatment. Its tolerance to the invasion of other weed species and the maintenance of forage species evenness was also superior. The total diversity was five times higher for the mixture communities as compared to the plant community in the control treatment. Therefore, using the suppressive pasture mixtures may provide an improved sustainable management approach for parthenium weed in grasslands.
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Sendall, Marguerite C., Lauren Fox, and Darren Wraith. "University Staff and Students’ Attitudes towards a Completely Smoke-Free Campus: Shifting Social Norms and Organisational Culture for Health Promotion." International Journal of Environmental Research and Public Health 18, no. 13 (July 2, 2021): 7104. http://dx.doi.org/10.3390/ijerph18137104.
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A large university in Queensland, Australia with a diverse staff and student community introduced a campus wide smoke-free policy in 2016. The purpose of this enquiry was to understand attitudes about a new smoke-free policy, its potential impact and the shift in social norms and organizational culture to inform the next phase of implementation. An electronic survey was distributed to all staff and students approximately 12 weeks after the smoke-free policy was implemented. The survey consisted of multiple-choice questions about demographics, smoking behaviour, attitudes towards smoking and tobacco control, awareness of the smoke-free policy, and attitudes towards the effect of a completely smoke-free campus on quality of life, learning and enrolment. The survey was completed by 641 university staff and students. Respondents reported seeking out (80.4%) and socialising in smoke-free environments (86.6%) and supported smoke-free buildings (96.1%), indoor areas (91.6%), and outdoor areas (79%). The results revealed overwhelming support for a completely smoke-free campus (83%) and minority support for designated smoking areas (31%). Overall, respondents reflected positively towards a campus wide smoke-free policy. These findings suggest Queensland’s early adoption of tobacco control laws influenced the social environment, de-normalised smoking, changed behaviour, preference for smoke-free environments and shifted social norms. These findings provide convincing evidence for organisational change and suggest health promotion policy makers should progress the implementation of smoke-free policies nationally across the higher education sector.
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Ferguson, J. Connor, Bhagirath S. Chauhan, Rodolfo G. Chechetto, Andrew J. Hewitt, Steve W. Adkins, Greg R. Kruger, and Chris C. O’Donnell. "Droplet-Size Effects on Control of Chloris spp. with Six POST Herbicides." Weed Technology 33, no. 1 (January 15, 2019): 153–58. http://dx.doi.org/10.1017/wet.2018.99.
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AbstractChloris spp. are warm-season grasses that outcompete crops for scarce resources throughout Australia. In Queensland, mild winters and increased adoption of conservation tillage practices have led to an increase of this warm-season grass family in winter crops. The objective of this study is to understand whether droplet size (nozzle type) effects herbicide efficacy of summer perennial grasses, as previous research found no effect of droplet size (nozzle type) on herbicide efficacy of winter annual grasses. A study to compare droplet-size (nozzle type) effects on control of windmillgrass and its domesticated relative, rhodesgrass, was conducted at the University of Queensland in Gatton, QLD, Australia. Results showed little difference in dry weight reductions for windmillgrass or rhodesgrass across droplet size (nozzle type). Paraquat applications with the TTI nozzle resulted in significantly lower dry weight reductions compared with other droplet-size sprays (nozzle types) for rhodesgrass. Glyphosate, imazamox plus imazapyr, and clodinafop resulted in commercially acceptable control for both species, regardless of the droplet size (nozzle type) selected, indicating droplet size (nozzle type) has relatively little impact on the efficacy of these herbicides. Proper nozzle selection can result in control of Chloris spp., a hard to control weed species, while reducing the occurrence of spray drift to nearby sensitive areas.
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Barnes, JE. "Molinate (S-ethyl hexahydro-1H-azepine-1-carbothioate) controls red rice (Oryza sativa) in the Burdekin Valley of North Queensland." Australian Journal of Experimental Agriculture 30, no. 6 (1990): 841. http://dx.doi.org/10.1071/ea9900841.
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Molinate controlled red rice (Oryza sativa) in commercial rice (O. sativa cv. Starbonnet) giving an increasing response at rates of 3.6, 4.3, 5.0, 5.7, 6.4, 7.2, 7.9 kg a.i./ha in 1 summer and 2 winter crops. No crop injury was observed at any rate of molinate, and grain yield, grain moisture, 1000-grain weight, head counts, grain number per head, germination counts, percentage bran and head yield were not affected. In 2 experiments, the percentage of whole grain was not affected by the chemical but in 1 experiment percentage whole grain increased with the rate of chemical used. Molinate provides a substantial level of control of red rice in commercial rice but the response to the herbicide is variable. In some crops weed suppression up to about 50% control is all that can be achieved, but in other crops controls of >90% are achievable. With the low levels of infestation that usually occur in North Queensland these levels of control are acceptable.
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Sharman, K. V. "Herbicides for Container-grown Rain Forest Species." HortScience 28, no. 4 (April 1993): 303–5. http://dx.doi.org/10.21273/hortsci.28.4.303.
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Four granular formulations of preemergence herbicides-oxadiazon, oxadiazon in combination with simazine, dichlobenil, and oxyfluorfen + oryzalin-were evaluated for weed control and phytotoxic effects on 10 species of container-grown Australian rain forest plants. Herbicides were applied at half and at one and two times the manufacturer's recommended rate. Oxyfluorfen + oryzalin, oxadiazon, and oxadiazon + simazine controlled all weed species at half the recommended rates (1.0 + 0.5, 2.0, and 2.0 + 0.5 kg·ha-1, respectively) with no phytotoxic effects after 10 weeks to nine of the 10 rain forest species tested: broad-leafed lilly-pilly [Acmena hemilampra (F. Muell. ex Bailey) Merr. and Perry], red ash [Alphitonia excelsa (Cunn. ex Fenzl) Reisseck ex Benth.], rusty bean [Dysoxylum rufum (A. Rich.) Benth.], macaranga [Macaranga tanarius (L.) Muell. Arg.], fibrous satinash [Syzygium fibrosum (Bailey) T. Hartley and Perry], Queensland golden myrtle [Metrosideros queenslandica L.S. Smith], cluster fig [Ficus racemosa L.], corduroy tamarind [Arytera lautereriana (Bailey) Radlk.], and celerywood [Polyscias elegans (F. Muell and C. Moore) Harms]. Dichlobenil depressed plant growth of red ash and failed to control bittercress (Cardamine hirsuta L.) and green amaranth (Amaranthus viridus L.), even at twice the recommended rate (4.0 kg·ha-1). All herbicides applied at half the recommended rates produced minor to moderate plant injury within 5 weeks of the first application to corduroy tamarind and northern silky oak [Cardwellia sublimis F. Muell.]. A second application 10 weeks after the first caused no significant plant injury to corduroy tamarind but resulted in severe plant injury to northern silky oak. This finding validates the previously reported sensitivity of Proteaceous spp. to preemergence herbicides. Chemical names used: (2-tert-butyl-4-(2,4-dichloro-5-isopropoxyphenyl)-Δ2-1,3,4 oxadiazoline-5-one) (oxadiazon); (2-chloro-4,6-bisethylamino-1,3,5-triazine) (simazine); 2,6-dichlorobenzonitrile (dichlobenil); 2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene (oxyfluorfen); and 3,5-dinitro-N4,N4 -dipropylsulfanilamide (oryzalin).
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Gilmore, Rose, Leanne Sakzewski, Jenny Ziviani, Sarah Mcintyre, Hayley Smithers Sheedy, Nicola Hilton, Tracey Williams, et al. "Multicentre, randomised waitlist control trial investigating a parent-assisted social skills group programme for adolescents with brain injuries: protocol for the friends project." BMJ Open 9, no. 8 (August 2019): e029587. http://dx.doi.org/10.1136/bmjopen-2019-029587.
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IntroductionAdolescents with brain injury frequently have difficulties with social competence, which persist into adulthood affecting their participation in daily life. To date, there has been limited research into the efficacy of social competence interventions in this population. Research from the Program for the Education and Enrichment of Relational Skills (PEERS) has demonstrated significant improvements in social competence skills, maintained at 1-year to 5-year follow-up, for adolescents with autism spectrum disorder. PEERS has not yet been tested among adolescents with brain injury. This protocol describes a pragmatic, parallel two-group pre-test post-test randomised waitlist control trial across two sites in Australia, which aims to evaluate the feasibility, acceptability and efficacy of PEERS in adolescents with brain injury compared with usual care.Methods and analysisForty adolescents with an acquired brain injury or cerebral palsy will be randomly assigned to either the 14-week PEERS group or waitlist care as usual group. The waitlist group will then receive PEERS following the 26-week retention time point. Outcomes will be assessed at baseline, 14 weeks (immediately postintervention) and 26 weeks follow-up (retention). The primary outcomes are self-report and parent report on the Social Skills Improvement System Rating Scales immediately post PEERS at 14 weeks. Secondary outcomes include increased frequency of get-togethers with peers with reduced conflict and increased adolescent self-reported knowledge of social skills. Acceptability and feasibility will be examined through qualitative analysis of focus group data collected after the completion of each group.Ethics and disseminationEthics approval has been granted by the Medical Research Ethics Committee Children’s Health Queensland Hospital and Health Service Human Research Ethics Committee (HREC/17/QRCH/87), The University of Queensland (2017000864) and the Cerebral Palsy Alliance Ethics Committee (20170802/HREC:EC00402). The findings will be disseminated in peer-reviewed journals, by conference presentation and newsletters to consumers.Trial registration numberACTRN12617000723381.
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Walpole, Euan Thomas, Philippa Youl, Danica Cossio, Michelle Frances Morris, and Shoni Philpot. "Development of key performance indicator (KPI) for real-time monitoring of treatment of early breast cancer to control socioeconomic and indigenous systemic bias." Journal of Clinical Oncology 40, no. 16_suppl (June 1, 2022): 10566. http://dx.doi.org/10.1200/jco.2022.40.16_suppl.10566.
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10566 Background: Disparity in outcome for different cancer groups exist particularly for indigenous and poor socioeconomic background. Patient and treatment data on a population basis was examined. Methods: Population data for the state of Queensland, Australia (population 5.2M) collected by Cancer Alliance Queensland as part of government cancer registry roles plus additional linked data available as a gazetted quality assurance committee was examined to find patients with early breast cancer treated with surgery, chemotherapy (CT) and radiotherapy (RT) between 2005-2015. Results: A cohort of 8279 women received treatment with 89.3% having the surgery, CT, RT sequence. Time to completement threshold was 37 weeks using empirical cutpoint estimation in Stata. Overall survival (OS) was 94% at 5 years if < 37 weeks versus 88.5% if not. (p < 0.001). Multivariate analysis of socioeconomic and clinical characteristics for survival was also significant for increasing age, indigenous status, socioeconomic disadvantage, multiple co morbidities and advancing disease stage. Private hospital cases had a better outcome. When delay is analysed between treatments, only time to CT from surgery > 9.5 weeks was significant for OS (HR 1.42 p < 0.001). Indigenous status, socioeconomic status and private facility no longer were significant. Multiple co morbidities and advanced stage were still significantly associated with poorer survival. Funnel plots of treatment centre show the association with public hospital treatment and lower volume centre with delay. Conclusions: This data is retrospective so can inform local service evaluation but implementation of a KPI for delay to adjuvant chemotherapy of 9.5 weeks can provide real time targets for patient care. We measured delay in the recent 5 years (before survival available) which shows consistent delays and it will included as a reporting function of MDT management software. Whilst the increased use of neoadjuvant CT will assist, systematic reporting of this KPI has potential to remove treatment biases for indigenous and lower socioeconomic patients. More recent data will be available for presentation.
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Vitelli, Joseph S., Barbara A. Madigan, and Peter E. van Haaren. "Control Techniques and Management Strategies for the Problematic Navua sedge (Cyperus aromaticus)." Invasive Plant Science and Management 3, no. 3 (November 2010): 315–26. http://dx.doi.org/10.1614/ipsm-d-09-00036.1.
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AbstractNavua sedge, a member of the Cyperaceae family, is an aggressive weed of pastures in Fiji, Sri Lanka, the Malay Peninsula, Vanuatu, Samoa, the Solomon Islands, and Tahiti and is now a weed of pastures and roadsides in north Queensland, Australia. Primarily restricted to areas with an annual rainfall exceeding 2,500 mm (98.4 in), Navua sedge is capable of forming dense stands, smothering many tropical pasture species. Seventeen herbicides were field tested at three sites in north Queensland, with glyphosate, halosulfuron, hexazinone, imazapic, imazapyr, or MSMA as the most effective for Navua sedge control. Environmental problems, such as persistence in soil, lack of selectivity, and movement off-site, may occur using some herbicides at the predicted 90% lethal concentration (LC90) control level rates. A seasonality trial using halosulfuron (97.5 g ai ha−1[1.4 oz ac−1]) gave better Navua sedge control (84%) by spraying in March to September than by spraying at other times (50%). In a frequency trial, sequential glyphosate applications (2,160 g ae ha−1) every 2 mo was more effective for continued Navua sedge control (67%) than a single application of glyphosate (36%), although loss of ground cover would occur. In a management trial, single applications of glyphosate (2,160 to 3,570 g ae ha−1) using either a rope wick, ground foliar spraying, or a rotary rope wick gave 59 to 73% control, whereas other treatments (rotary hoe, 3%; slashing, −13%; crushing, −30%) were less effective. In a second management trial, four monthly rotary wick applications were much more effective (98%) than four monthly crushing applications (42%). An effective management plan must include the application of regular herbicide treatments to eliminate Navua sedge seed being added to the soil seed bank. Treatments that result in seed burial, for example, discing, are likely to prolong seed persistence and should be avoided. The sprouting activity of vegetative propagules and root fragmentation also needs to be considered when selecting control options.
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Stirling, GR, LL Vawdrey, and EL Shannon. "Options for controlling needle nematode (Paralongidorus australis) and preventing damage to rice in northern Queensland." Australian Journal of Experimental Agriculture 29, no. 2 (1989): 223. http://dx.doi.org/10.1071/ea9890223.
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Options for the control of Paralongidorus australis on paddy rice in northern Queensland were evaluated in a series of field and pot experiments. Soil fumigation with 1,3-dichloropropene at 220 and 358 kglha gave excellent control in the field and increased grain yields by more than 40%. In pots, carbofuran (5, 10 and 20 kg a.i./ha) applied to soil prior to sowing or in water at the time of permanent flooding gave good control but fenamiphos and CuSO4 did not. These results suggested that the amounts of 1,3-dichloropropene or carbofuran needed to control the nematode were too high for annual treatment with nematicides to be economic. Carbofuran and oxamyl applied as seed dressings at 0.75% and 0.36% a.i. respectively were much cheaper treatments, but failed to control P. australis or reduce nematode damage to root tips. P. australis was eliminated from moist soil by air-drying, but this effect could not be reproduced in the field by deep ripping followed by cultivation to break up clods. Amendment of nematode-infested soil with straw and various sulfur-containing compounds and flooding for 6 or 12 weeks, failed to reduce nematode numbers in the subsequent rice crop, indicating that products of anaerobic decomposition did not control the nematode. However, there was a marked reduction in the percentage of root tips damaged by the nematode in the straw + sulphur treatment. Additional pot experiments investigated practices that reduced losses from P. australis but did not necessarily control the nematode. When rice was flooded 1, 2, 3, 5 or 7 weeks after sowing, the degree of nematode damage was reduced as flooding was delayed, possibly because P. australis remained inactive during the period prior to flooding. Of the 14 rice cultivars and breeding lines tested for tolerance to P. australis, several cultivars were more tolerant than Starbonnet and Lemont, the cultivars currently being grown commercially in northern Queensland. Both delayed flooding and the use of tolerant varieties showed enough promise to warrant further testing in the field.
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Chadha, Aakansha, Singarayer K. Florentine, Kunjithapatham Dhileepan, and Christopher Turville. "Assessing Seed Longevity of the Invasive Weed Navua Sedge (Cyperus aromaticus), by Artificial Ageing." Plants 11, no. 24 (December 11, 2022): 3469. http://dx.doi.org/10.3390/plants11243469.
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Navua sedge (Cyperus aromaticus (Ridley) Mattf. & Kukenth) is a significant agricultural and environmental weed found in tropical island countries including north Queensland, Australia. It is a prolific seed producer and consequently forms a high-density seedbank, and therefore understanding the longevity and persistence of the seeds can provide critical information required for the management of this species. A laboratory-controlled artificial ageing experiment was conducted where the seeds were exposed to a temperature of 45 °C and 60% relative humidity for 125 days. Seeds were removed at various times (1, 2, 5, 9, 20, 30, 50, 75, 100 and 125 days) and their viability determined through standard germination tests. It took 20 days in the artificial ageing environment for the seeds to decline to 50% viability which indicates that Navua sedge has relatively short-lived persistent seeds. These findings will assist in developing a better understanding of the seedbank dynamics of this invasive species, allowing managers to tactically implement control strategies and prepare budgets for ongoing treatments, and have implications for the duration and success of management programs.
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Ergashev. "Analysis of Gross Margins in Queensland Tomatoes." Proceedings 36, no. 1 (January 16, 2020): 48. http://dx.doi.org/10.3390/proceedings2019036048.
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Tomato is an important vegetable crop that contributes significantly to income security and healthy diets of people worldwide. Queensland produces the majority of tomatoes for fresh consumption accounting for 40 per cent of national supply in Australia. The purpose of this study is to provide an analytical summary of the Queensland tomato supply chain, by focusing on margins along the supply chain. For that, a representative tomato gross margin model in Southern Queensland was used to analyse the estimated income, grouped variable costs and the gross margin for four tomato varieties: gourmet, round, grape, and cherry. The mean yields of the sampled varieties varied considerably, depending on climatic conditions, pests and diseases, the season and whether tomatoes are grown on the ground or trellises. Driven by high revenues and relatively low freight costs, grape tomatoes have the highest gross margin ($73 thousand per hectare) as well as the highest market price at $4.64 per kilo compared to other varieties. The cost of growing the crop up to harvest can exceed $10,000 per hectare with high labour requirement for harvesting and packing. While costs for machinery, fertiliser, herbicide, weed control, insecticide, and fungicide largely remain constant across four tomato varieties, it is planting and irrigation that makes a difference. With average value of $9,303 per hectare, planting costs range from $5,134 for round tomatoes to $12,241 for cherry tomatoes. The results of this gross margin analysis can be helpful to explore profitability at the farm level, allowing regional and international comparisons
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Dhileepan, K. "Biological Control of Parthenium (Parthenium hysterophorus) in Australian Rangeland Translates to Improved Grass Production." Weed Science 55, no. 5 (October 2007): 497–501. http://dx.doi.org/10.1614/ws-07-045.1.
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Biological control of parthenium, a major weed in grazing areas in Australia, was initiated in the mid 1970s. Since then, nine species of insects and two rust fungi have been introduced. Evaluation using pesticide exclusion at two sites (Mt. Panorama and Plain Creek) in Queensland, Australia, revealed that classical biological control had a significant negative effect on the target weed, but the impact varied between years. In this study, I quantified the effects of biological control of parthenium on grass production. Grass production declined with the increase in parthenium biomass. Significant increase in grass production due to biological control was observed, but only in 1 of 4 yr at Mt. Panorama and 2 of 4 yr at Plain Creek. At Mt. Panorama, there was a 40% increase in grass biomass in 1997 because of defoliation by Zygogramma bicolorata and galling by Epiblema strenuana. At Plain Creek, grass biomass increased by 52% in 1998 because of E. strenuana and by 45% in 2000 because of combined effects of E. strenuana and the summer rust Puccinia melampodii. This study provides evidence on the beneficial effects of biological control of parthenium in areas under limited grazing.
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Singh, Aseemjot, Gulshan Mahajan, and Bhagirath Singh Chauhan. "Germination ecology of wild mustard (Sinapis arvensis) and its implications for weed management." Weed Science 70, no. 1 (October 1, 2021): 103–11. http://dx.doi.org/10.1017/wsc.2021.66.
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AbstractWild mustard (Sinapis arvensis L.) is a widespread weed of the southeastern cropping region of Australia. Seed germination ecology of S. arvensis populations selected from different climatic regions may differ due to adaptative traits. Experiments were conducted to evaluate the effects of temperature, light, radiant heat, soil moisture, salt concentration, and burial depth on seed germination and seedling emergence of two populations (Queensland [Qld] population: tropical region; and Victoria [Vic] population: temperate region) of S. arvensis. Both populations germinated over a wide range of day/night (12-h/12-h) temperatures (15/5 to 35/25 C), and had the highest germination at 30/20 C. Under complete darkness, the Qld population (61%) had higher germination than the Vic population (21%); however, under the light/dark regime, both populations had similar germination (78% to 86%). At 100 C pretreatment for 5 min, the Qld population (44%) had higher germination than the Vic population (13%). Germination of both populations was nil when given pretreatment at 150 and 200 C. The Vic population was found tolerant to high osmotic and salt stress compared with the Qld population. At an osmotic potential of −0.4 MPa, germination of Qld and Vic populations was reduced by 85% and 42%, respectively, compared with their respective controls. At 40, 80, and 160 mM sodium chloride, germination was lower for the Qld population than the Vic population. Averaged over the populations, seedling emergence was highest (52%) from a burial depth of 1 cm and was nil from 8-cm depth. Differential germination behaviors of both populations to temperature, light, radiant heat, water stress, and salt stress suggest that populations of S. arvensis may have undergone differential adaptation. Knowledge gained from this study will assist in developing suitable control measures for this weed species to reduce the soil seedbank.
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Costello, Benjamin, Olusegun O. Osunkoya, Juan Sandino, William Marinic, Peter Trotter, Boyang Shi, Felipe Gonzalez, and Kunjithapatham Dhileepan. "Detection of Parthenium Weed (Parthenium hysterophorus L.) and Its Growth Stages Using Artificial Intelligence." Agriculture 12, no. 11 (November 2, 2022): 1838. http://dx.doi.org/10.3390/agriculture12111838.
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Parthenium weed (Parthenium hysterophorus L. (Asteraceae)), native to the Americas, is in the top 100 most invasive plant species in the world. In Australia, it is an annual weed (herb/shrub) of national significance, especially in the state of Queensland where it has infested both agricultural and conservation lands, including riparian corridors. Effective control strategies for this weed (pasture management, biological control, and herbicide usage) require populations to be detected and mapped. However, the mapping is made difficult due to varying nature of the infested landscapes (e.g., uneven terrain). This paper proposes a novel method to detect and map parthenium populations in simulated pastoral environments using Red-Green-Blue (RGB) and/or hyperspectral imagery aided by artificial intelligence. Two datasets were collected in a control environment using a series of parthenium and naturally co-occurring, non-parthenium (monocot) plants. RGB images were processed with a YOLOv4 Convolutional Neural Network (CNN) implementation, achieving an overall accuracy of 95% for detection, and 86% for classification of flowering and non-flowering stages of the weed. An XGBoost classifier was used for the pixel classification of the hyperspectral dataset—achieving a classification accuracy of 99% for each parthenium weed growth stage class; all materials received a discernible colour mask. When parthenium and non-parthenium plants were artificially combined in various permutations, the pixel classification accuracy was 99% for each parthenium and non-parthenium class, again with all materials receiving an accurate and discernible colour mask. Performance metrics indicate that our proposed processing pipeline can be used in the preliminary design of parthenium weed detection strategies, and can be extended for automated processing of collected RGB and hyperspectral airborne unmanned aerial vehicle (UAV) data. The findings also demonstrate the potential for images collected in a controlled, glasshouse environment to be used in the preliminary design of invasive weed detection strategies in the field.
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McKenzie, John, Dannielle Brazier, Shane Campbell, Joseph Vitelli, Angela Anderson, and Robert Mayer. "Foliar herbicide control of sticky florestina (Florestina tripteris DC.)." Rangeland Journal 36, no. 3 (2014): 259. http://dx.doi.org/10.1071/rj13091.
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Sticky florestina (Florestina tripteris DC.) is an annual exotic weed that has become naturalised near the townships of Tambo and Barcaldine in central western Queensland, Australia. Three experiments conducted near Barcaldine identified foliar herbicides effective in killing sticky florestina plants and in providing residual activity to reduce recruitment from the soil seed bank. An initial chemical screening experiment evaluated the efficacy of 28 herbicide treatments. The most promising herbicides were then further evaluated in two response-rate experiments. Overall, 2,4-D/picloram, aminopyralid/fluroxypyr, clopyralid, metsulfuron-methyl and triclopyr/picloram proved to be the most effective selective herbicides. Two of these, metsulfuron-methyl at 18 g active ingredient (a.i) ha–1 and 2,4-D + picloram at 900 g a.i. ha–1 + 225 g a.i. ha–1 have now been included in a minor use permit (PER11920) with the Australian Pesticides and Veterinary Medicines Authority (APVMA) for the control of sticky florestina in pasture, stock route, roadside and non-crop situations using both spot and boom-spray applications (APVMA 2010). The permit also allows the use of 2,4-D amine for the control of seedlings only.
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Cogle, AL, RJ Bateman, and DH Heiner. "Conservation cropping systems for the semi-arid tropics of North Queensland, Australia." Australian Journal of Experimental Agriculture 31, no. 4 (1991): 515. http://dx.doi.org/10.1071/ea9910515.
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A farming systems project was commenced in the semi-arid tropics of north-eastern Australia to assess the cropping potential and reliability of a newly developing region. Emphasis was placed on evaluation of conservation cropping systems, since it was expected that these would be the most successful and protective uses of the land. This paper discusses the agronomy of peanuts, maize and sorghum grown under different conservative cropping practices (reduced tillage, no tillage, ley) on the soil (red earth) most likely to be developed for large-scale cropping in the region. Crop yields with all practices were limited by establishment difficulties including high soil temperatures, poor weed control and climatic variability. Reduced tillage was more successful than no tillage due to higher yields in dry years; however, in wet years no tillage produced similar yields. The ley cropping system may have some advantages in this environment for integrated production and resource protection.
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Bebawi, F. F., and S. D. Campbell. "Effects of fire on germination and viability of bellyache bush (Jatropha gossypiifolia) seeds." Australian Journal of Experimental Agriculture 42, no. 8 (2002): 1063. http://dx.doi.org/10.1071/ea01125.
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If treatments imposed to control exotic plants also have a deleterious impact on their residual seed bank, the duration and extent of follow-up control may be reduced. Fire is one such technique that has this ability, particularly if seeds are located on or close to the soil surface. Three studies were undertaken in a riparian habitat in the dry tropics of northern Queensland to quantify the effects of spring burning on the seed bank of the exotic weed bellyache bush (Jatropha gossypiifolia). The first determined the distribution of seeds within the vertical profile of the trial site. The other 2 studies were experiments that quantified the effects of fire on germination and viability of both dispersed bellyache bush seeds and seeds held in mature capsules. Dispersed seeds of 2 types (intact and ant-discarded) were placed at the following 6 positions in the vertical profile of bellyache bush infestations: 0.5, 1, 2 and 4 cm depth below ground, on bare ground, and below fuel. Seeds held in capsules were located at random on the crown of bellyache bush plants. For both experiments, comparisons of burnt plots were made with unburnt controls. Fire was imposed in spring (September); the season in which burning for weed control in northern Queensland generally occurs. While maximum fire temperatures averaged 590 ± 46°C, the temperatures that seeds or capsules were exposed to depended on their location within the vertical profile, with temperatures decreasing in the following order: below fuel > crown of bellyache bush > 1 cm > 0.5 cm > bare ground > 2 cm > 4 cm below ground. There were negative correlations between seed germination and peak fire temperature and between viability and peak fire temperature. Seed viability was nil for seed under fuel but >80% for seeds placed on bare ground or ≥2 cm below ground. Fire reduced germination and viability of seeds held in capsules by 31 and 35%, respectively, when compared with unburnt seeds. While ant-discarded seeds generally had a higher germinability than intact seeds, they were more susceptible to fire. This may be attributed to loss of the external protective barrier of the seed coat (exotegmen) caused by the feeding of ants. Bellyache bush seeds were recorded across all soil depths, reaching a peak of 3.8 million seeds per hectare at 1–5 cm soil depth. These results suggest that while bellyache bush seeds are susceptible to fire, many are buried beyond the reach of lethal temperatures. Therefore, viable seeds will be available for post-fire recruitment and other measures, such as chemical control, may need to be employed in conjunction with burning.
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Dohn, Justin, Z. Carter Berry, and Timothy J. Curran. "A pilot project testing the effectiveness of three weed control methods on the removal ofLantana camarain Forty Mile Scrub National Park, Queensland, Australia." Ecological Management & Restoration 14, no. 1 (January 2013): 74–77. http://dx.doi.org/10.1111/emr.12031.
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Rafter, M. A., W. A. Palmer, and G. H. Walter. "Assessing the biological control potential of an adventitiously-established “pest”, Scirtothrips aurantii (Faure), on a weed, Bryophyllum delagoense (Eckl. & Zeyh.), in Queensland." Biological Control 58, no. 3 (September 2011): 346–53. http://dx.doi.org/10.1016/j.biocontrol.2011.05.004.
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Winks, R., MA Burns, DA Berrie, IJ East, JG Kelly, and KC Bremner. "Effect of repeated anthelmintic treatment on weight gain in Hereford and Brahman crossbred cattle in south-eastern Queensland." Australian Journal of Experimental Agriculture 27, no. 2 (1987): 189. http://dx.doi.org/10.1071/ea9870189.
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Hereford and Brahman crossbred steers were treated with the injectable anthelmintic, levamisole, at either 3-, 6- or 12-week intervals for 8 months after weaning. Throughout the studies, the different treatment groups were maintained on separate pastures with the exception of 1 group in which half of the animals were treated 3-weekly and the others were untreated. A further untreated group was grazed separately. The trial was repeated with different groups of weaners in 3 successive years. The major gastrointestinal nematodes infecting the cattle were Haemonchus placei, Oesophagostomum radiatum, Cooperia pectinata and Cooperia punctata. The Hereford weaners treated every 3 or 6 weeks showed significantly greater weight gains than untreated steers, but those treated every 12 weeks did not. In 2 of the 3 years. Brahman-cross weaners showed a significant increase in weight gain with the 3-week schedule but not with the 6- and 12-week schedules. Twelve months after treatment ended, the final liveweights of the treated groups did not differ significantly from those of the control groups for either Hereford or Brahman crossbred cattle.
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Walker, SR, JMT Marley, GR Robinson, and PA Hargreaves. "Initial activity of atrazine and chlorsulfuron residues is greater in the grey clays than in the black earths of southern Queensland." Australian Journal of Experimental Agriculture 34, no. 1 (1994): 67. http://dx.doi.org/10.1071/ea9940067.
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Commercial experience is that soil type appears to be a major factor influencing initial weed control from soil applications of atrazine and chlorsulfuron. We tested this by collecting 26 soils from the major cropping areas in southern Queensland. Initial activity was determined by measuring the dose required for 50% inhibition (ID50) of seedling growth in Wimmera ryegrass in controlled environment cabinets. The mean ID50 for atrazine and chlorsulfuron in black earths was 3 and 4 times greater, respectively, than in grey clays. Lower activity in the black earths was probably due to higher clay and cation contents and, consequently, greater adsorption of the herbicides. These results suggest that application rates of atrazine and chlorsulfuron can be adjusted for differences in initial activity between soil types.
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Kliese, Y. J., R. C. Dalal, W. M. Strong, and N. W. Menzies. "Piggery pond sludge as a nitrogen source for crops. 1. Mineral N supply estimated from laboratory incubations and field application of stockpiled and wet sludge." Australian Journal of Agricultural Research 56, no. 3 (2005): 245. http://dx.doi.org/10.1071/ar04187.
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Piggery pond sludge (PPS) was applied, as-collected (Wet PPS) and following stockpiling for 12 months (Stockpiled PPS), to a sandy Sodosol and clay Vertosol at sites on the Darling Downs of Queensland. Laboratory measures of N availability were carried out on unamended and PPS-amended soils to investigate their value in estimating supplementary N needs of crops in Australia’s northern grains region. Cumulative net N mineralised from the long-term (30 weeks) leached aerobic incubation was described by a first-order single exponential model. The mineralisation rate constant (0.057/week) was not significantly different between Control and PPS treatments or across soil types, when the amounts of initial mineral N applied in PPS treatments were excluded. Potentially mineralisable N (No) was significantly increased by the application of Wet PPS, and increased with increasing rate of application. Application of Wet PPS significantly increased the total amount of inorganic N leached compared with the Control treatments. Mineral N applied in Wet PPS contributed as much to the total mineral N status of the soil as did that which mineralised over time from organic N. Rates of CO2 evolution during 30 weeks of aerobic leached incubation indicated that the Stockpiled PPS was more stabilised (19–28% of applied organic C mineralised) than the Wet PPS (35–58% of applied organic C mineralised), due to higher lignin content in the former. Net nitrate-N produced following 12 weeks of aerobic non-leached incubation was highly correlated with net nitrate-N leached during 12 weeks of aerobic incubation (R2 = 0.96), although it was <60% of the latter in both sandy and clayey soils. Anaerobically mineralisable N determined by waterlogged incubation of laboratory PPS-amended soil samples increased with increasing application rate of Wet PPS. Anaerobically mineralisable N from field-moist soil was well correlated with net N mineralised during 30 weeks of aerobic leached incubation (R2 = 0.90 sandy soil; R2 = 0.93 clay soil). In the clay soil, the amount of mineral N produced from all the laboratory incubations was significantly correlated with field-measured nitrate-N in the soil profile (0–1.5 m depth) after 9 months of weed-free fallow following PPS application. In contrast, only anaerobic mineralisable N was significantly correlated with field nitrate-N in the sandy soil. Anaerobic incubation would, therefore, be suitable as a rapid practical test to estimate potentially mineralisable N following applications of different PPS materials in the field.
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Kliese, Y. J., R. C. Dalal, W. M. Strong, and N. W. Menzies. "Corrigendum to: Piggery pond sludge as a nitrogen source for crops. 1. Mineral N supply estimated from laboratory incubations and field application of stockpiled and wet sludge." Australian Journal of Agricultural Research 56, no. 12 (2005): 1415. http://dx.doi.org/10.1071/ar04187_co.
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Piggery pond sludge (PPS) was applied, as-collected (Wet PPS) and following stockpiling for 12 months (Stockpiled PPS), to a sandy Sodosol and clay Vertosol at sites on the Darling Downs of Queensland. Laboratory measures of N availability were carried out on unamended and PPS-amended soils to investigate their value in estimating supplementary N needs of crops in Australia's northern grains region. Cumulative net N mineralised from the long-term (30 weeks) leached aerobic incubation was described by a first-order single exponential model. The mineralisation rate constant (0.057/week) was not significantly different between Control and PPS treatments or across soil types, when the amounts of initial mineral N applied in PPS treatments were excluded. Potentially mineralisable N (No) was significantly increased by the application of Wet PPS, and increased with increasing rate of application. Application of Wet PPS significantly increased the total amount of inorganic N leached compared with the Control treatments. Mineral N applied in Wet PPS contributed as much to the total mineral N status of the soil as did that which mineralised over time from organic N. Rates of CO2 evolution during 30 weeks of aerobic leached incubation indicated that the Stockpiled PPS was more stabilised (19.28% of applied organic C mineralised) than the Wet PPS (35.58% of applied organic C mineralised), due to higher lignin content in the former. Net nitrate-N produced following 12 weeks of aerobic non-leached incubation was highly correlated with net nitrate-N leached during 12 weeks of aerobic incubation (R2 = 0.96), although it was <60% of the latter in both sandy and clayey soils. Anaerobically mineralisable N determined by waterlogged incubation of laboratory PPS-amended soil samples increased with increasing application rate of Wet PPS. Anaerobically mineralisable N from field-moist soil was well correlated with net N mineralised during 30 weeks of aerobic leached incubation (R2 = 0.90 sandy soil; R2 = 0.93 clay soil). In the clay soil, the amount of mineral N produced from all the laboratory incubations was significantly correlated with field-measured nitrate-N in the soil profile (0.1.5 m depth) after 9 months of weed-free fallow following PPS application. In contrast, only anaerobic mineralisable N was significantly correlated with field nitrate-N in the sandy soil. Anaerobic incubation would, therefore, be suitable as a rapid practical test to estimate potentially mineralisable N following applications of different PPS materials in the field.
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Armstrong, Ellen L., Roslyn N. Boyd, Megan J. Kentish, Christopher P. Carty, and Sean A. Horan. "Effects of a training programme of functional electrical stimulation (FES) powered cycling, recreational cycling and goal-directed exercise training on children with cerebral palsy: a randomised controlled trial protocol." BMJ Open 9, no. 6 (June 2019): e024881. http://dx.doi.org/10.1136/bmjopen-2018-024881.
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IntroductionChildren with cerebral palsy (CP) experience declines in gross motor ability as they transition from childhood to adolescence, which can result in the loss of ability to perform sit-to-stand transfers, ambulate or participate in leisure activities such as cycling. Functional electrical stimulation (FES) cycling is a novel technology that may provide opportunities for children with CP to strengthen their lower limbs, improve functional independence and increase physical activity participation. The proposed randomised controlled trial will test the efficacy of a training package of FES cycling, adapted cycling and goal-directed functional training to usual care in children with CP who are susceptible to functional declines.Methods and analysisForty children with CP (20 per group), aged 6–8 years and classified as Gross Motor Function Classification System (GMFCS) levels II–IV will be recruited across South East Queensland. Participants will be randomised to either an immediate intervention group, who will undertake 8 weeks of training, or a waitlist control group. The training group will attend two 1 hour sessions per week with a physiotherapist, consisting of FES cycling and goal-directed, functional exercises and a 1 hour home exercise programme per week, consisting of recreational cycling. Primary outcomes will be the gross motor function measure and Canadian occupational performance measure, and secondary outcomes will include the five times sit-to-stand test, habitual physical activity (accelerometry), power output during cycling and Participation and Environment Measure-Children and Youth. Outcomes will be assessed at baseline, postintervention (8 weeks) and 8 weeks following the intervention (retention).Ethics and disseminationEthical approval has been obtained from Griffith University (2018/037) and the Children’s Health Queensland Hospital and Health Service (CHQHHS) Human Research Ethics Committee (HREC/17/QRCH/88). Site-specific approval was obtained from CHQHHS research governance (SSA/17/QRCH/145). Results from this trial will be disseminated via publication in relevant peer-reviewed journals.Trial registration numberACTRN12617000644369p.
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Bebawi, Faiz F., Shane D. Campbell, and Robert J. Mayer. "Gamba grass (Andropogon gayanus Kunth.) seed persistence and germination temperature tolerance." Rangeland Journal 40, no. 5 (2018): 463. http://dx.doi.org/10.1071/rj17125.
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Gamba grass (Andropogon gayanus Kunth.) is a highly invasive, naturalised Weed of National Significance in Australia due to its economic, environmental and social impacts. It outcompetes native pastures and fuels intense fires in northern Australian rangelands. To aid management of current infestations and to better understand its potential distribution, this study determined the germination response of gamba grass under a range of constant (13°C−48°C) and alternating (11/7°C–52/42°C) temperature regimes and quantified the potential longevity of soil seed banks. The effect of different soil types, levels of pasture cover and burial depths on seed longevity was investigated in the Dry Tropics of northern Queensland. Germination of gamba grass occurred under a wide range of both constant (17°C−39°C) and alternating day/night temperatures (16/12°C–47/39°C), although the level of germination declined at the lower and higher temperature ranges. At the cooler temperatures, seed viability was not affected, but seeds went into a state of dormancy. The highest level of seed viability was recorded at the lowest constant temperature regime (13°C) and at the two lowest alternating temperatures (11/7°C and 16/12°C). A gradual but variable decline in viability occurred thereafter with increasing temperatures. At the higher temperature range (e.g. constant temperatures of 39°C−43°C and alternating temperatures of 47/39°C) both dormancy and loss of seed viability were occurring, but once alternating and constant temperatures reached above 47/39°C and 43°C all seeds were rendered unviable after 9 and 6 weeks respectively. In the Dry Tropics of northern Queensland, viability of seeds was <1% after 12 months and nil after 24 months, irrespective of soil type or vegetation cover. However, burial depth had a significant effect, with surface located seeds exhibiting a faster rate of decline in germination and viability than seeds buried below ground (i.e. 2.5–10 cm). These findings have implications for the duration of control/eradication programs (i.e. seed persistence) and also suggest that gamba grass has the potential to greatly expand its current distribution into the relatively cooler southern latitude areas of Australia.
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Shi, Boyang, Olusegun O. Osunkoya, Aakansha Chadha, Singarayer K. Florentine, and Kunjithapatham Dhileepan. "Biology, Ecology and Management of the Invasive Navua Sedge (Cyperus aromaticus)—A Global Review." Plants 10, no. 9 (September 7, 2021): 1851. http://dx.doi.org/10.3390/plants10091851.
Full textAbstract:
Navua sedge (Cyperus aromaticus (Ridley) Mattf. & Kukenth) is an invasive perennial sedge, native to tropical Africa, which is threatening many natural ecosystems and agroecosystems, especially in northern Queensland, Australia. Crop and pasture production have been impacted by Navua sedge and it is also directly causing reductions in dairy and beef production in affected regions. This review documents the biology, ecology and potential management options to minimise the spread and impact of Navua sedge. The weed reproduces both sexually (seeds) and vegetatively (via underground rhizomes). Its tiny seeds can be spread easily via wind, water, vehicles, farm machinery and animals, whilst the rhizomes assist with establishment of dense stands. The CLIMEX model (which uses distribution and climate data in native and novel ranges) indicates that in Australia, Navua sedge has the potential to spread further within Queensland and into the Northern Territory, New South Wales and Victoria. Several management strategies, including mechanical, chemical and agronomic methods, and their integration will have to be used to minimise agricultural production losses caused by Navua sedge, but most of these methods are currently either ineffective or uneconomical when used alone. Other management approaches, including biological control and mycoherbicides, are currently being explored. We conclude that a better understanding of the interaction of its physiological processes, ecological patterns and genetic diversity across a range of conditions found in the invaded and native habitats will help to contribute to and provide more effective integrated management approaches for Navua sedge.