Siga este link para ver outros tipos de publicações sobre o tema: Weeds South Australia.
Artigos de revistas sobre o tema "Weeds South Australia"
Crie uma referência precisa em APA, MLA, Chicago, Harvard, e outros estilos
Veja os 50 melhores artigos de revistas para estudos sobre o assunto "Weeds South Australia".
Ao lado de cada fonte na lista de referências, há um botão "Adicionar à bibliografia". Clique e geraremos automaticamente a citação bibliográfica do trabalho escolhido no estilo de citação de que você precisa: APA, MLA, Harvard, Chicago, Vancouver, etc.
Você também pode baixar o texto completo da publicação científica em formato .pdf e ler o resumo do trabalho online se estiver presente nos metadados.
Veja os artigos de revistas das mais diversas áreas científicas e compile uma bibliografia correta.
1
Spennemann, D. H. R., e L. R. Allen. "Feral olives ( Olea europaea) as future woody weeds in Australia: a review". Australian Journal of Experimental Agriculture 40, n.º 6 (2000): 889. http://dx.doi.org/10.1071/ea98141.
Texto completo da fonteResumo:
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.
2
Latif, Sajid, Saliya Gurusinghe, Paul A. Weston, William B. Brown, Jane C. Quinn, John W. Piltz e Leslie A. Weston. "Performance and weed-suppressive potential of selected pasture legumes against annual weeds in south-eastern Australia". Crop and Pasture Science 70, n.º 2 (2019): 147. http://dx.doi.org/10.1071/cp18458.
Texto completo da fonteResumo:
Mixed farming systems have traditionally incorporated subterranean clover (Trifolium subterraneum L.) and lucerne (Medicago sativa L.) as key components of the pasture phase across south-eastern Australia. However, poor adaptation of subterranean clover to acidic soils, insufficient and inconsistent rainfall, high input costs, soil acidification and the emergence of herbicide-resistant weeds have reduced efficacy of some traditional clover species in recent years. To overcome these challenges, numerous novel pasture species have been selectively improved and released for establishment in Australia. Despite their suitability to Australian climate and soils, limited knowledge exists regarding their weed-suppressive ability in relation to establishment and regeneration. Field trials were therefore conducted over 3 years in New South Wales to evaluate the suppressive potential of selected pasture legume species and cultivars as monocultures and in mixed stands against dominant annual pasture weeds. Pasture and weed biomass varied significantly between pasture species when sown as monocultures, but mixtures of several species did not differ with regard to establishment and subsequent weed infestation. Arrowleaf clover (T. vesiculosum Savi.) and biserrula (Biserrula pelecinus L.) cv. Casbah showed improved stand establishment, with higher biomass and reduced weed infestation compared with other pasture species. Generally, weed suppression was positively correlated with pasture biomass; however, yellow serradella (Ornithopus compressus L.) cv. Santorini exhibited greater weed suppression than other pasture legumes while producing lower biomass, thereby suggesting a mechanism other than competition for resources affecting weed-suppressive ability. Over the period 2015–17, arrowleaf clover and biserrula cv. Casbah were generally the most consistent annual pasture legumes with respect to yearly regeneration and suppression of annual pasture weed species.
3
Scott, John K. "Biology and climatic requirements of Perapion antiquum (Coleoptera: Apionidae) in southern Africa: implications for the biological control of Emexspp. in Australia". Bulletin of Entomological Research 82, n.º 3 (setembro de 1992): 399–406. http://dx.doi.org/10.1017/s0007485300041195.
Texto completo da fonteResumo:
AbstractThe potential distribution of the South African weevil, Perapion antiquum (Gyllenhal), a biological control agent for the weeds Emex spp., was deter mined by the computer program CLIMEX, using its native distribution, phenology and abundance together with development parameters. The predicted distribution included parts of Hawaii where the weevil successfully controlled Emex australis and E. spinosa. In Australia, sites of past unsuccessful releases have climates that this analysis indicates are unsuitable for the insect. The most favourable regions for establishment of the weevil are near the coast in the southern half of Australia, but most of these do not overlap with regions where Emex spp. are a problem. In western Cape Province, South Africa, E. australis plants are abundant and the weevil attacks the plant after seeds have formed. In Hawaii, a fortuitous combination of climatic conditions favours the weevil during the period after seed germination, and this may be the key to its control of the weed. Sites with climatic conditions similar to successful control sites in Hawaii are not found in Australia. It was concluded that P. antiquum will be of limited use as a biological control agent in Australia even in areas suitable for its establishment.
4
Graham, Sonia, e Sarah Rogers. "How Local Landholder Groups Collectively Manage Weeds in South-Eastern Australia". Environmental Management 60, n.º 3 (6 de abril de 2017): 396–408. http://dx.doi.org/10.1007/s00267-017-0859-7.
Texto completo da fonte
5
Hurst, Thomas, e Paul I. Boon. "Agricultural weeds and coastal saltmarsh in south-eastern Australia: an insurmountable problem?" Australian Journal of Botany 64, n.º 4 (2016): 308. http://dx.doi.org/10.1071/bt16027.
Texto completo da fonteResumo:
It is often assumed that saline coastal wetlands experience environmental conditions so severe that they are largely immune to invasion by exotic plant species. The belief is implicit in many older reviews of threats to mangroves and coastal saltmarshes, where a limited range of vascular plant taxa, often focussing on *Spartina, (throughout the paper an asterisk denotes an introduced (exotic) species as per Carr 2012) have been invoked as the major species of concern. Even though the weed flora of southern Australia is derived largely from agriculture and horticulture, neither of which includes many species tolerant of waterlogged, variably saline environments, a recent assessment of Victorian saline coastal wetlands indicated that exotic plants were the third-most pervasive threat, after land ‘reclamation’ and grazing. Tall wheat grass, *Lophopyrum ponticum (Podp.) A.Love., is one of the most severe and widely distributed weeds of saline coastal wetlands in south-eastern Australia. It is promoted by the agricultural extension arm of the Victorian government as a salt-tolerant pasture grass; however, its broad ecological amplitude and robust life form make it a most serious invader of upper saltmarsh in Victoria. We assessed the effectiveness of different control measures, including slashing and herbicides, for the management of *L. ponticum infestations (and their side effects on saltmarsh communities) in the Western Port region of Victoria. A nominally monocot-specific herbicide widely used to control *Spartina, Fluazifop-P, was ineffective in controlling *L. ponticum. The broad-spectrum systemic herbicide glyphosate was more effective in controlling *L. ponticum, but had undesirable impacts on native plant species. Controlling weeds in coastal wetlands using available herbicides for use near coastal waterways would seem to remain problematic.
6
Borger, Catherine P. D., Abul Hashem e Shahab Pathan. "Manipulating Crop Row Orientation to Suppress Weeds and Increase Crop Yield". Weed Science 58, n.º 2 (junho de 2010): 174–78. http://dx.doi.org/10.1614/ws-09-094.1.
Texto completo da fonteResumo:
Crop rows oriented at a right angle to sunlight direction (i.e., east–west within the winter cropping system in Western Australia) may suppress weed growth through greater shading of weeds in the interrow spaces. This was investigated in the districts of Merredin and Beverley, Western Australian (latitudes of 31° and 32°S) from 2002 to 2005 (four trials). Winter grain crops (wheat, barley, canola, lupines, and field peas) were sown in an east–west or north–south orientation. Within wheat and barley crops oriented east–west, weed biomass (averaged throughout all trials) was reduced by 51 and 37%, and grain yield increased by 24 and 26% (compared with crops oriented north–south). This reduction in weed biomass and increase in crop yield likely resulted from the increased light (photosynthetically active radiation) interception by crops oriented east–west (i.e., light interception by the crop canopy as opposed to the weed canopy was 28 and 18% greater in wheat and barley crops oriented east–west, compared with north–south crops). There was no consistent effect of crop row orientation in the canola, field pea, and lupine crops. It appears that manipulation of crop row orientation in wheat and barley is a useful weed-control technique that has few negative effects on the farming system (i.e., does not cost anything to implement and is more environmentally friendly than chemical weed control).
7
Lemerle, D., B. Verbeek e S. Diffey. "Influences of field pea (Pisum sativum) density on grain yield and competitiveness with annual ryegrass (Lolium rigidum) in south-eastern Australia". Australian Journal of Experimental Agriculture 46, n.º 11 (2006): 1465. http://dx.doi.org/10.1071/ea04233.
Texto completo da fonteResumo:
The variation in field pea grain yield and competitiveness with annual ryegrass due to crop density, row spacing and cultivar was determined to enable farmers to better manage weeds with cultural control tactics. Crop density varied with seeding rate, cultivar, row spacing and year. Higher seeding rates were required to reach equivalent plant densities in cv. Dinkum (short, semi-leafless) compared with cv. Dundale (tall, conventional-leaf), and at 36 cm compared with 18 cm row spacing. Field pea grain yield was reduced more at low crop densities, in Dinkum, at 36 cm row spacing, and in the presence of weeds. Percentage yield losses from weed competition were similar in both cultivars (about 70–80%) at a low density of 10 plants/m2 in 2 seasons. At higher crop densities Dinkum had a larger loss than Dundale (i.e. at 30 plants/m2 losses were 60 and 35%, respectively, compared with 50 and 5% at 60 plants/m2). Seasonal variation influenced the effect of crop density on yield loss from weeds. The percentage yield loss from weeds in 1993 ranged from about 90 to 40% at plant densities of 10 to 40 plants/m2, in contrast to 1995 when 40% yield loss occurred at all these densities. Ryegrass dry weight was reduced with increasing field pea density in both years, and in the tall more than the short cultivar in 1 year. Maintaining recommended field pea seeding rates has considerable financial benefits in both weed-free (around $100/ha) and weed-affected crops (to $400/ha). In weedy situations, integrating cultural practices such as higher seeding rates and choice of cultivar that enhance crop competitiveness will improve weed management in south-eastern Australia.
8
Walker, S. R., I. N. Taylor, G. Milne, V. A. Osten, Z. Hoque e 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, n.º 1 (2005): 79. http://dx.doi.org/10.1071/ea03189.
Texto completo da fonteResumo:
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.
9
Michael, Pippa J., Catherine P. Borger, William J. Macleod e Pip L. Payne. "Occurrence of Summer Fallow Weeds within the Grain Belt Region of Southwestern Australia". Weed Technology 24, n.º 4 (dezembro de 2010): 562–68. http://dx.doi.org/10.1614/wt-d-09-00060.1.
Texto completo da fonteResumo:
Field surveys were conducted on 319 sites of the Western Australian grain belt in 2006 to determine the occurrence and distribution of summer fallow weed species. Sites were located across five growing season regions (north, north central, central, south central, and south) and three annual rainfall zones (high, medium, and low). A total of 51 species (or species groups) from 18 families were identified, with the large majority of species (35%) belonging to the Poaceae family. The most prevalent species found, being present at more than 10% of all sites, were wheat, “melons” (weedy watermelon and paddymelon), rigid ryegrass, capeweed, clover, mintweed, wild radish, fleabane, windmill grass, and rolypoly. Correspondence analysis revealed that the north, central, and southern regions of the grain belt could be predominately segregated according to dominant weed species occurrence; however, no segregation by rainfall zone was apparent. This study has given an overview of summer fallow weed occurrence in the Western Australian grain belt and highlights those weed species that are common and yet lack sufficient research into their ecology and management.
10
Manalil, Sudheesh, Jeff Werth, Rod Jackson, Bhagirath Singh Chauhan e Christopher Preston. "An assessment of weed flora 14 years after the introduction of glyphosate-tolerant cotton in Australia". Crop and Pasture Science 68, n.º 8 (2017): 773. http://dx.doi.org/10.1071/cp17116.
Texto completo da fonteResumo:
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.
11
Scott, J. K., e P. B. Yeoh. "Bionomics and the predicted distribution of the aphid Brachycaudus rumexicolens (Hemiptera: Aphididae)". Bulletin of Entomological Research 89, n.º 1 (janeiro de 1999): 97–106. http://dx.doi.org/10.1017/s0007485399000127.
Texto completo da fonteResumo:
AbstractDevelopment rates of the aphid, Brachycaudus rumexicolens (Patch), a recent arrival in Australia and a potential biological control agent against weeds in the family Polygonaceae, were measured over a range of constant temperatures. The theoretical lower limit for development is 6.4°C and the upper limit 32°C. Maximum fecundity per day was reached at 19°C. The rate of increase peaked at about 28°C giving a population doubling time of less than two days. These values were used with the current distribution to develop a CLIMEX model to predict the potential world distribution of the aphid. The model predicts that the aphid has suitable periods of population growth in autumn and spring, and that survival is unlikely over summer in most of south-western Australia where the aphid has the potential to contribute to the biological control of the polygonaceous weeds, Emex and Rumexspecies. The model predicts that years with cool summer temperatures and late summer rains in south west Australia, such as in 1990 when the aphid was first abundant, will be particularly suitable for aphid development. These conditions occurred twice between 1985 and 1995. To increase the effectiveness of the aphid as a biological control agent of weeds in other years, augmentation by provision of alternative hosts and/or the release of mass reared individuals during autumn is proposed.
12
Leys, AR, RL Amor, AG Barnett e B. Plater. "Evaluation of herbicides for control of summer-growing weeds on fallows in south-eastern Australia". Australian Journal of Experimental Agriculture 30, n.º 2 (1990): 271. http://dx.doi.org/10.1071/ea9900271.
Texto completo da fonteResumo:
Eighteen herbicides or herbicide tankmixes were evaluated over 3 years (1987-89) for their control of 11 important summer-growing weeds on fallows in southern New South Wales and the Wimmera area of Victoria. Each of the weeds was effectively controlled by at least 1 herbicide. The tank-mixes of glyphosate plus metsulfuron (270 + 4.2 g a.i./ha) and glyphosate plus 2,4-D ester (270 + 320 g a.i./ha) were the most effective treatments, each giving an average of 68% control of all species. Hogweed (Polygolzunz avicu1ar.e L.), prickly paddy melon (Cucumis myriocarpris Naudin), spear thistle [Cirsium vulgare (Savi) Ten.] and skeleton weed (Chondrilla juncea L.) were the species most tolerant of these 2 tank-mixes. When these species were exluded, glyphosate plus metsulfuron and glyphosate plus 2,4-D ester gave an average of 90 and 88% control, respectively, of the remaining species [common heliotrope, Heliotropiunz europaeum L.; camel melon, Citrullus larzatus (Thunb.) Matsum. and Nakai var. lanatus; prickly lettuce, Lactuca serriola L.; sowthistle, Sonchus spp.; clammy goosefoot, Chenopodium pumilio R.Br.; caltrop, Tribulus terrestris L.; stink grass, Eragrostis ciliatiensis (All.) E. Mosher]. Hogweed was most effectively controlled by 2,4-D amine plus dicamba (750 + 100 g a.i./ha) or 2,4-D ester (800 g a.i./ha); prickly paddy melon by 2,4-D amine plus triclopyr (750 + 96 g a.i./ha); spear thistle by 2,4-D amine plus dicamba (750 + 100 g a.i./ha) or glyphosate plus clopyralid (270 + 60 g a.i./ha); and skeleton weed by 2,4-D amine plus clopyralid (750 + 60 g a.i./ha). A pot experiment confirmed field observations that, as common heliotrope ages, glyphosate and glyphosate plus metsulfuron become less effective for its control.
13
Ajamian, Chad, Hsing-Chung Chang, Kerrie Tomkins, William Farebrother, Rene Heim e Shahriar Rahman. "Identifying Invasive Weed Species in Alpine Vegetation Communities Based on Spectral Profiles". Geomatics 1, n.º 2 (1 de abril de 2021): 177–91. http://dx.doi.org/10.3390/geomatics1020011.
Texto completo da fonteResumo:
This study examined the use of hyperspectral profiles for identifying three selected weed species in the alpine region of New South Wales, Australia. The targeted weeds included Orange Hawkweed, Mouse-ear Hawkweed and Ox-eye daisy, which have caused a great concern to regional biodiversity and health of the environment in Kosciuszko National Park. Field surveys using a spectroradiometer were undertaken to measure the hyperspectral profiles of leaves and flowers of the selected weeds and companion native plants. Random Forest (RF) classification was then applied to distinguish which spectral bands would differentiate the weeds from the native plants. Our results showed that an accuracy of 95% was achieved if the spectral profiles of the distinct flowers of the weeds were considered, and an accuracy of 80% was achieved if only the profiles of the leaves were considered. Emulation of the spectral profiles of two multispectral sensors (Sentinel-2 and Parrot Sequoia) was then conducted to investigate whether classification accuracy could potentially be achieved using wider spectral bands.
14
Rozefelds, A. C. F., L. Cave, D. I. Morris e A. M. Buchanan. "The weed invasion in Tasmania since 1970". Australian Journal of Botany 47, n.º 1 (1999): 23. http://dx.doi.org/10.1071/bt97054.
Texto completo da fonteResumo:
Tasmanian Herbarium (HO) collections are shown to provide temporal and distributional data to monitor weed introductions into the State flora during the last 25 years. Information obtained from herbarium collections, the botanical literature, and anecdotal sources indicates that since 1970, 159 new plant taxa have been recorded as naturalised in Tasmania, bringing to a total over 740 weed species recorded from the State. Most of these species are from the families Poaceae (15.1%), Fabaceae (10.1%), Asteraceae (6.9%), Cyperaceae (5.7%), Rosaceae s.l. (5.0%), Caryophyllaceae and Liliaceae s.l. (3.8% each), Iridaceae (3.1%), and Juncaceae and Ranunculaceae (2.5% each). While for many taxa the mechanisms for introduction remain unknown, at least 35% were introduced as ornamentals, and some 5% arrived through agricultural practices. Of the 159 species, 19 are known only from Tasmania and have not been recorded from the Australian mainland. The majority of weeds are of European origin, with a high proportion being from Africa, North and South America, and mainland Australia, in that order. This study demonstrates that even with the current quarantine controls a large number of weed species have been introduced to the State flora in the last 25 years, and a considerable number of these species are recognised as potential environmental weeds. The number of new weed species recognised is also possibly due, in part, to more collections of weeds being undertaken in recent years. As a large percentage of the weeds identified are ornamentals, stricter controls on the introductions of new ornamentals may be needed. Some of the limitations of using herbarium collections to assess weed introductions are also discussed.
15
Metcalf, William (Bill). "The Fall and Rise of an Antipodean Utopia: Brisbane, Australia". Utopian Studies 19, n.º 2 (1 de janeiro de 2008): 189–211. http://dx.doi.org/10.2307/20719899.
Texto completo da fonteResumo:
Abstract This article describes and discusses a late-nineteenth century utopian text, The Curse and Its Cure, set in the city of Brisbane, capital of the state of Queensland, Australia. The first half of this book by Dr. Thomas Pennington Lucas posits how Brisbane was utterly destroyed in the early twentieth century so that by the time at which the story is set—in the year 2000—little remains of the abandoned city except scattered ruins overrun with weeds and vermin. In the second half, Lucas postulates how, by the year 2200, Brisbane had become the New Jerusalem in the South Pacific, a true Utopia leading the world to morality, affluence, peace, and sanity. The Curse and Its Cure has long been out of print and, as far as can be discovered, only one full copy and one partial copy remain, both held by the John Oxley Library, Brisbane. I uncovered it as part of my research into Australia's utopian literature. Although other Australian scholars such as Nan Albinski, Vincent Buckley, Verity Burgmann, Andrew Milner, Bruce Scates, Richard Trahair, and Robyn Walton (as well as an American academic, Lyman Tower Sargent) have all written about the prodigious amount of Australian utopian literature, none of them discovered Lucas's text.
16
Metcalf, William (Bill). "The Fall and Rise of an Antipodean Utopia: Brisbane, Australia". Utopian Studies 19, n.º 2 (1 de janeiro de 2008): 189–211. http://dx.doi.org/10.5325/utopianstudies.19.2.0189.
Texto completo da fonteResumo:
Abstract This article describes and discusses a late-nineteenth century utopian text, The Curse and Its Cure, set in the city of Brisbane, capital of the state of Queensland, Australia. The first half of this book by Dr. Thomas Pennington Lucas posits how Brisbane was utterly destroyed in the early twentieth century so that by the time at which the story is set—in the year 2000—little remains of the abandoned city except scattered ruins overrun with weeds and vermin. In the second half, Lucas postulates how, by the year 2200, Brisbane had become the New Jerusalem in the South Pacific, a true Utopia leading the world to morality, affluence, peace, and sanity. The Curse and Its Cure has long been out of print and, as far as can be discovered, only one full copy and one partial copy remain, both held by the John Oxley Library, Brisbane. I uncovered it as part of my research into Australia's utopian literature. Although other Australian scholars such as Nan Albinski, Vincent Buckley, Verity Burgmann, Andrew Milner, Bruce Scates, Richard Trahair, and Robyn Walton (as well as an American academic, Lyman Tower Sargent) have all written about the prodigious amount of Australian utopian literature, none of them discovered Lucas's text.
17
Seymour, M. "Narbon bean (Vicia narbonensis) agronomy in south-western Australia". Australian Journal of Experimental Agriculture 46, n.º 10 (2006): 1355. http://dx.doi.org/10.1071/ea04091.
Texto completo da fonteResumo:
Narbon bean (Vicia narbonensis L.) shows promise as a fodder, green manure and grain crop in south-western Australia. This study examines the effect of time of sowing (2 experiments), plant density (3 experiments) and reaction to herbicides (4 experiments on tolerance to herbicides and 1 experiment on removing narbon bean from a wheat crop) in 10 separate field experiments sown at 4 locations in the mallee region of Western Australia from 1998 to 2001. Narbon bean was found to be unresponsive to changes in sowing date with yield maintained until the first week of June. The optimum plant density (90% of fitted maximum) for seed yield was found to be 31 plants/m2, equivalent to sowing rates in the range of 75–100 kg/ha. A wide range of herbicides applied either before sowing or immediately after sowing and before emergence had no significant effect on grain yield. These included simazine (750 g a.i./ha), cyanazine (1.25 kg a.i./ha) and diuron (500 g a.i./ha), which were applied immediately before sowing, and imazethapyr (29 g a.i./ha), which was applied after sowing, before emergence. Diflufenican (75 g a.i./ha) was found to be the only available option for post-emergence control of broadleaf weeds. The use of the non-selective herbicides glyphosate (450 g a.i./L) and Sprayseed 250 (paraquat 135 g a.i./L and diquat 115 g a.i./L) as post-emergence herbicides was found to be unpredictable at a range of application rates. Results ranged from a yield loss of 47% to a yield increase of 23%. In an experiment to test a range of herbicides for the selective control of narbon bean within a wheat crop, numerous herbicides were found to effectively remove volunteer narbon bean indicating that narbon bean is unlikely to become a weed in most cereal cropping systems.
18
Taylor, AJ. "Influence of weed competition on autumn-sown lucerne in south-eastern Australia and the field comparison of herbicides and mowing for weed control". Australian Journal of Experimental Agriculture 27, n.º 6 (1987): 825. http://dx.doi.org/10.1071/ea9870825.
Texto completo da fonteResumo:
A field experiment in autumn-sown lucerne was conducted at Tatura to quantify the growth of winter weeds and the effects of weeds on lucerne seedling establishment, plant densities and hay production over the first year of cutting. In addition, mowing treatments and a range of herbicides were evaluated with respect to weed control. Weed growth rates in spring of up to 114 kg ha-l day-1 DM and high yields of annual winter weeds excluded lucerne (Medicago sativa L. cv. Delkalb 167) almost entirely from the first hay cut and significantly reduced seedling vigour and plant densities. The unsprayed control plots yielded 9.3 t ha-1 at the first hay cut and comprised 52% capeweed, 41% ryegrass and less than 1% lucerne. In other treatments where either capeweed or ryegrass remained uncontrolled, the proportion of lucerne in the hay was low. Weeds significantly reduced lucerne yields (P < 0.01) at the first and second hay cuts of 5 cuts taken in the first season. Combinations of herbicides gave the best weed control and highest lucerne yield at the first and second cuts and significantly higher total lucerne yield. The best herbicide combination was trifluralin and bromoxynil, which controlled all weed species on the site, reduced the weed yield at the first cut by 87% below that of the control and produced the highest total lucerne yield of 14 t ha-l. The hay composition of this treatment at the first cut comprised 59% lucerne, 27% ryegrass and 14% other weed species, while at the second hay cut lucerne comprised 95% of the DM. Lucerne was the highest yielding species in all treatments at the second cut. Lucerne plant densities were lowest on the unsprayed control plots, with 56% fewer plants than for the herbicide combination treatments. Mowing in August was effective in preventing the decline in lucerne plant density that occurred on the unsprayed control plots.
19
Osten, V. A., S. R. Walker, A. Storrie, M. Widderick, P. Moylan, G. R. Robinson e K. Galea. "Survey of weed flora and management relative to cropping practices in the north-eastern grain region of Australia". Australian Journal of Experimental Agriculture 47, n.º 1 (2007): 57. http://dx.doi.org/10.1071/ea05141.
Texto completo da fonteResumo:
The main weeds and weed management practices undertaken in broad acre dryland cropping areas of north-eastern Australia have been identified. The information was collected in a comprehensive postal survey of both growers and agronomists from Dubbo in New South Wales (NSW) through to Clermont in central Queensland, where 237 surveys were returned. A very diverse weed flora of 105 weeds from 91 genera was identified for the three cropping zones within the region (central Queensland, southern Queensland and northern NSW). Twenty-three weeds were common to all cropping zones. The major common weeds were Sonchus oleraceus, Rapistrum rugosum, Echinochloa spp. and Urochloa panicoides. The main weeds were identified for both summer and winter fallows, and sorghum, wheat and chickpea crops for each of the zones, with some commonality as well as floral uniqueness recorded. More genera were recorded in the fallows than in crops, and those in summer fallows exceeded the number in winter. Across the region, weed management relied heavily on herbicides. In fallows, glyphosate and mixes with glyphosate were very common, although the importance of the glyphosate mix partner differed among the cropping zones. Use and importance of pre-emergence herbicides in-crop varied considerably among the zones. In wheat, more graminicides were used in northern NSW than in southern Queensland, and virtually none were used in central Queensland, reflecting the differences in winter grass weed flora across the region. Atrazine was the major herbicide used in sorghum, although metolachlor was also used predominantly in northern NSW. Fallow and inter-row cultivation were used more often in the southern areas of the region. Grazing of fallows was more prominent in northern NSW. High crop seeding rates were not commonly recorded indicating that growers are not using crop competition as a tool for weed management. Although many management practices were recorded overall, few growers were using integrated weed management, and herbicide resistance has been and continues to be an issue for the region.
20
E. Twigg, Laurie, Tim J. Lowe e Gary R. Martin. "The presence and implications of viable seed in the faeces of invasive free-ranging European Rabbits and Red Foxes". Pacific Conservation Biology 15, n.º 3 (2009): 158. http://dx.doi.org/10.1071/pc090158.
Texto completo da fonteResumo:
Invasion by weeds and other undesirable plants threatens global biodiversity. However, the role of mammals in maintaining and spreading weeds is often overlooked. Here we confirm that two widely distributed and abundant Australian mammalian pests, the European Rabbit (Oryctolagus cuniculus) and the Red Fox (Vulpes vulpes), can spread viable seed. Our assessment mainly involved determining the number and viability of seeds recovered from faeces of free-ranging individuals inhabiting several areas within the Mediterranean region of south-western Australia, an internationally recognized biodiversity hotspot. In summer, viable seeds were recovered from 3?4% of the rabbit faecal pellets (n = 190) compared to 21?40% of pellets in autumn (n = 235). Ten (77%) of the 13 species of seed identified were weeds. Of the 1,136 seeds recovered, 16% germinated. In all, 13-30% of rabbits passed viable seeds in summer, increasing to 44?73% of rabbits in autumn. In captive wild rabbits, mean passage time of marked seed through the intestinal tract ranged from 4?7 h. This, together with the small home ranges of Australian European rabbits, suggests that they may generally disperse seeds over 1?2 km. Nine to 27% of foxes passed viable seed. Although 48% of scats (n = 62) contained whole seed, only 12.9% of all scats contained viable seed (range 9.1%?19.0%). Viable seeds (4/8) were also recovered from the hides of some shot foxes. In all, 63% (12/19) of seed species identified in the scats and pelts of foxes were weeds. Rabbits (primary dispersal) and foxes (primary, and secondary dispersal via seeds ingested with prey) may be important dispersers of viable seed, and may be essential for less common, but important, long-distance plant dispersal, particularly by some invasive species. Thus, suppression of weeds can be added to the benefits of reducing the abundance of rabbits and foxes to protect the unique biota and agricultural production in southwestern Australia.
21
Chejara, Vinod K., Paul Kristiansen, R. D. B. (Wal) Whalley, Brian M. Sindel e Christopher Nadolny. "The role of seedbanks in invasions by Hyparrhenia hirta (L.) Stapf in Australia". Rangeland Journal 41, n.º 5 (2019): 383. http://dx.doi.org/10.1071/rj19039.
Texto completo da fonteResumo:
Hyparrhenia hirta (L.) Stapf (also known as Coolatai grass, South African bluestem or thatching grass) has become a serious invasive weed in Australia. Within its native range, it is generally regarded as a useful grass particularly for thatching, and seed production is low with a low soil seed bank of from 2 to 200seedsm–2. Several hundred accessions of H. hirta were deliberately introduced into Australia up until the 1980s and nearly all were discarded because of poor seed production. However, at least one introduction in the 1890s in northern New South Wales (NSW), Australia, has possibly contributed to the present serious weed problem. Annual seed production from roadside stands in northern NSW ranged from 7000 to 92000seedsm–2 in 2015. The soil seed bank under dense H. hirta infestations in the same region in 2006 and 2007, was found to be ~30000seedsm–2 mostly confined to the top 2cm, with few dormant seeds and a large reduction of these numbers over the next 12 months when further seed input was prevented. Similar studies of other perennial grass weeds have found seed banks of similar sizes, but dormancy mechanisms ensure that their seed banks last for at least 10 years without further seed input. These results suggest that the present weedy populations of H. hirta have dramatically increased fecundity enabling a large seed bank to develop beneath dense stands. The development of seed dormancy and consequently a long-lived seed bank would make this weed even more difficult to control. Until seed dormancy develops, control of H. hirta in northern NSW can be effective provided further input into the seed bank can be prevented.
22
Robinson, D. E., J. T. O’Donovan, M. P. Sharma, D. J. Doohan e R. Figueroa. "The biology of Canadian weeds. 123. Senecio vulgaris L." Canadian Journal of Plant Science 83, n.º 3 (1 de julho de 2003): 629–44. http://dx.doi.org/10.4141/p01-124.
Texto completo da fonteResumo:
Senecio vulgaris L. is a native of Eurasia, and has been introduced to and become naturalized in North America, South America, Africa and Australia. In Canada, it is found in all provinces and the Northwest and Yukon Territo ries. High fecundity, rapid wind dispersal, continuous germination under a wide range of growing conditions, rapid growth rate, ability to set seed a number of times per growing season and lack of chemical control options has made this species an importan t weed of some horticultural crops. This species produces pyrrolizidine alkaloids that have been implicated as a cause of liver toxicity in livestock. Populations of S. vulgaris have displayed resistance to Group 5, 6 and 7 herbicides (triazines, uracils, substituted ureas and nitriles) and other photosynthetic-transport-inhibiting herbicides. Triazine resistance in S. vulgaris was the first reported case of herbicide resistance worldwide. A rust pathogen, Puccinia lagenophorae Cooke, is currently being evaluated for control of S. vulgaris in Europe. Key words:
23
Owen, Mechelle J., Neree J. Martinez e Stephen B. Powles. "Herbicide resistance in Bromus and Hordeum spp. in the Western Australian grain belt". Crop and Pasture Science 66, n.º 5 (2015): 466. http://dx.doi.org/10.1071/cp14293.
Texto completo da fonteResumo:
Random surveys conducted in the Western Australian (WA) grain belt have shown that herbicide-resistant Lolium rigidum and Raphanus raphanistrum are a widespread problem across the cropping region. In 2010, a random survey was conducted to establish the levels of herbicide resistance for common weed species in crop fields, including the minor but emerging weeds Bromus and Hordeum spp. This is the first random survey in WA to establish the frequency of herbicide resistance in these species. For the annual grass weed Bromus, 91 populations were collected, indicating that this species was present in >20% of fields. Nearly all populations were susceptible to the commonly used herbicides tested in this study; however, a small number of populations (13%) displayed resistance to the acetolactate synthase-inhibiting sulfonylurea herbicides. Only one population displayed resistance to the acetyl-coenzyme A carboxylase-inhibiting herbicides. Forty-seven Hordeum populations were collected from 10% of fields, with most populations being susceptible to all herbicides tested. Of the Hordeum populations, 8% were resistant to the sulfonylurea herbicide sulfosulfuron, some with cross-resistance to the imidazolinone herbicides. No resistance was found to glyphosate or paraquat, although resistance to these herbicides has been documented elsewhere in Australia for Hordeum spp. (Victoria) and Bromus spp. (Victoria, South Australia and WA).
24
Peterson, David J., e Raj Prasad. "The biology of Canadian weeds. 109. Cytisus scoparius (L.) Link". Canadian Journal of Plant Science 78, n.º 3 (1 de julho de 1998): 497–504. http://dx.doi.org/10.4141/p97-079.
Texto completo da fonteResumo:
Scotch broom (Cytisus scoparius [L.] Link.) is an exotic perennial, leguminous, deciduous shrub, which during the past century has greatly expanded its range along the Pacific and Atlantic coasts of North America, and in Australia, New Zealand, South Africa, Chile, Iran, and India. This shrub rapidly invades disturbed areas, forming dense thickets, which can suppress and inhibit native vegetation, including economically important conifer seedlings. The developmental characteristics whereby Scotch broom invades new sites include specialized stem photosynthesis, prolific seed production, longevity of seeds in the soil, and nitrogen fixation. Human activities such as planting along highways for beautification and prevention of soil erosion have accelerated the problem of rapid geographical dispersal. Various methods of control (chemical, manual, and biological) together with habitat, morphology, reproductive biology, growth and development are discussed. Key words: Cytisus scoparius, Ulex europaeus, Scotch broom, invasive weeds, bioherbicides, Fusarium tumidu
25
Freeman, Angela Joan, e Mohammad Aftab. "Effective management of viruses in pulse crops in south eastern Australia should include management of weeds". Australasian Plant Pathology 40, n.º 4 (1 de junho de 2011): 430–41. http://dx.doi.org/10.1007/s13313-011-0058-6.
Texto completo da fonte
26
Campbell, MH. "Extending the frontiers of aerially sown pastures in temperate Australia: a review". Australian Journal of Experimental Agriculture 32, n.º 1 (1992): 137. http://dx.doi.org/10.1071/ea9920137.
Texto completo da fonteResumo:
Over the past 40 years large areas of pastures on hill country in temperate Australia have been improved through aerial distribution of herbicides, pesticides, seed, and fertiliser, which has increased animal production and helped to control weeds. Refinements detailed in this review could extend the use of these techniques to promote sustainable systems by the establishment of perennial pasture species on unploughed land. It is argued that the most urgent requirement is ensuring that aerial spraying is not abolished by government regulation in response to demands by specialist groups, because perennial pasture species will not establish on hill country without prior aerial spraying of herbicides. The major technical refinement needed is the reduction of losses of establishing plants due to weed competition and dry periods during their first spring and summer. This could be accomplished by increasing the spectrum of weeds controlled by the most widely used herbicide, glyphosate; applying new herbicides that give longer weed control in spring than the presently used herbicides; using herbicides that can selectively remove annual grass weeds from establishing perennial grasses; or using strategic grazing with cattle or goats to reduce weed competition. Breeding, selecting or importing pasture species specifically designed for establishment from surface sowing has never been attempted. Attributes that could improve establishment include germination that occurs only under favourable conditions; seeds resistant to weathering on the soil surface; seedlings with fast radicle entry, hairs on the radicle, fast root development, and better seedling vigour; and for subtropical species sown in semi-arid New South Wales, tolerance of low winter temperatures. Improved distribution of herbicides, seeds and fertilisers, particularly in the more rugged hill country, is needed to ensure complete cover of the treated area with minimum drift. Techniques that allow establishment of aerially sown pastures on hill country with very acid soil are needed to facilitate the development of further, large areas of Australia.
27
Adair, R. J., e J. K. Scott. "Distribution, life history and host specificity of Chrysolina picturata and Chrysolina sp. B (Coleoptera: Chrysomelidae), two biological control agents for Chrysanthemoides monilifera (Compositae)". Bulletin of Entomological Research 87, n.º 4 (agosto de 1997): 331–41. http://dx.doi.org/10.1017/s0007485300037354.
Texto completo da fonteResumo:
AbstractThe southern African shrubs Chrysanthemoides monilifera monilifera and C. m. rotundata (Compositae) are serious weeds of native vegetation in Australia and are targets for classical biological control. In host specificity tests using 69 species from 25 families, two leaf-feeding chrysomelid beetles, Chrysolina picturata (Clark) and Chrysolina sp. B, were able to complete development on only Chrysanthemoides monilifera and C. incana. The subspecies Chrysanthemoides m. monilifera was the superior host for both Chrysolina picturata and Chrysolina sp. B. Feeding and limited development of both species occurred on Calendula officinalis; limited development by Chrysolina picturata larvae occurred on Helianthus annuus, Tussilago farfara and Cymbonotus priessianus. Chrysolina picturata and Chrysolina sp. B are considered to be Chrysanthemoides-specific and have been approved for release in Australia. Potential release sites for both Chrysolina species were chosen by comparing the climate of the insects' African distribution with climate stations within the range of Chrysanthemoides monilifera in Australia. Chrysolina picturata and Chrysolina sp. B are suited for release within the western distribution of Chrysanthemoides m. monilifera in coastal areas of south eastern South Australia.
28
Nitschke, Monika, David Simon, Keith Dear, Kamalesh Venugopal, Hubertus Jersmann e Katrina Lyne. "Pollen Exposure and Cardiopulmonary Health Impacts in Adelaide, South Australia". International Journal of Environmental Research and Public Health 19, n.º 15 (26 de julho de 2022): 9093. http://dx.doi.org/10.3390/ijerph19159093.
Texto completo da fonteResumo:
(1) Background: Limited research has suggested that cardiopulmonary health outcomes should be considered in relation to pollen exposure. This study sets out to test the relationship between pollen types (grasses, trees, weeds) and cardiovascular, lower respiratory and COPD health outcomes using 15 years (2003–2017) of data gathered in Adelaide, South Australia; (2) Methods: A time-series analysis by months was conducted using cardiopulmonary data from hospital admissions, emergency presentations and ambulance callouts in relation to daily pollen concentrations in children (0–17) for lower respiratory outcomes and for adults (18+). Incidence rate ratios (IRR) were calculated over lags from 0 to 7 days; (3) Results: IRR increases in cardiovascular outcomes in March, May, and October were related to grass pollen, while increases in July, November, and December were related to tree pollen. IRRs ranged from IRR 1.05 (95% confidence interval (CI) 1.00–1.10) to 1.25 (95% CI 1.12–1.40). COPD increases related to grass pollen occurred only in May. Pollen-related increases were observed for lower respiratory outcomes in adults and in children; (4) Conclusion: Notable increases in pollen-related associations with cardiopulmonary outcomes were not restricted to any one season. Prevention measures for pollen-related health effects should be widened to consider cardiopulmonary outcomes.
29
Zona, Scott. "The correct gender of Schinus (Anacardiaceae)". Phytotaxa 222, n.º 1 (7 de agosto de 2015): 75. http://dx.doi.org/10.11646/phytotaxa.222.1.9.
Texto completo da fonteResumo:
Species of the genus Schinus Linnaeus (1753) (Anacardiaceae) are native to the Americas but are found in many tropical and subtropical parts of the world, where they are cultivated as ornamentals or crops (“pink peppercorns”) or they are invasive weeds. Schinus molle L. (1753: 388) is a cultivated ornamental tree in Australia, California, Mexico, the Canary Islands, the Mediterranean, and elsewhere (US Forest Service 2015). In Hawaii, Florida, South Africa, Mascarene Islands, and Australia, Schinus terebinthifolia Raddi (1820: 399) is an aggressively invasive pest plant, costing governments millions of dollars in damages and control (Ferriter 1997).
30
Latham, L. J., L. J. Smith e R. A. C. Jones. "Incidence of three viruses in vegetable brassica plantings and associated wild radish weeds in south-west Australia". Australasian Plant Pathology 32, n.º 3 (2003): 387. http://dx.doi.org/10.1071/ap03031.
Texto completo da fonte
31
Harries, Martin, Ken C. Flower, Craig A. Scanlan, Michael T. Rose e Michael Renton. "Interactions between crop sequences, weed populations and herbicide use in Western Australian broadacre farms: findings of a six-year survey". Crop and Pasture Science 71, n.º 5 (2020): 491. http://dx.doi.org/10.1071/cp19509.
Texto completo da fonteResumo:
Six years of survey data taken from 184 paddocks spanning 14 million ha of land used for crop and pasture production in south-west Western Australia were used to assess weed populations, herbicide resistance, integrated weed management (IWM) actions and herbicide use patterns in a dryland agricultural system. Key findings were that weed density within crops was low, with 72% of cropping paddocks containing fewer than 10 grass weeds/m2 at anthesis. Weed density and herbicide resistance were not correlated, despite the most abundant grass weed species (annual ryegrass, Lolium rigidum Gaudin) testing positive for resistance to at least one herbicide chemistry in 92% of monitored paddocks. A wide range of herbicides were used (369 unique combinations) suggesting that the diversity of herbicide modes of action may be beneficial for reducing further development of herbicide resistance. However, there was a heavy reliance on glyphosate, the most commonly applied active ingredient. Of concern, in respect to the evolution of glyphosate resistant weeds, was that 45% of glyphosate applications to canola were applied as a single active ingredient and area sown to canola in Western Australia expanded from 0.4 to 1.4 million hectares from 2005 to 2015. In order to minimise the weed seed bank within crops, pastures were used infrequently in some regions and in 50% of cases pastures were actively managed to reduce weed seed set, by applying a non-selective herbicide in spring. The use of non-selective herbicides in this manner also kills pasture plants, consequently self-regenerating pastures were sparse and contained few legumes where cropping intensity was high. Overall, the study indicated that land use selection and utilisation of associated weed management actions were being used successfully to control weeds within the survey area. However, to successfully manage herbicide resistant weeds land use has become less diverse, with pastures utilised less and crops with efficacious weed control options utilised more. Further consideration needs to be given to the impacts of these changes in land use on other production factors, such as soil nutrient status and plant pathogens to assess sustainability of these weed management practices in a wider context.
32
Black, ID, CB Dyson e AR Fischle. "Applications of the herbicide sethoxydim increase wheat yield in the absence of weeds". Australian Journal of Experimental Agriculture 36, n.º 5 (1996): 555. http://dx.doi.org/10.1071/ea9960555.
Texto completo da fonteResumo:
In 11 experiments over 6 seasons the herbicide sethoxydim was applied to Machete, Spear and Blade wheat cultivars in the absence or near absence of weeds (10 sites) or where the weeds were controlled by selective herbicides (1 site), in the cropping area north of Adelaide, South Australia. The rates applied included 9-47 g a.i./ha at the 2-3 leaf growth stage and 9-74 g a.i./ha at early tillering. Except for the very long growing season of 1992, there was a highly significant positive linear correlation between the number of degree days in the growing season at each experimental site and relative mean yield increase of these sethoxydim treatments. Yield increases ranged from nil in growing seasons of about 1000 degree days to 32% in a growing season of 1480 degree days, with a median of 8% over the experiments.
33
Pérez-Fernández, María A., Byron B. Lamont, Anjanette L. Marwick e Wesley G. Lamont. "Germination of seven exotic weeds and seven native speciesin south-western Australia under steady and fluctuating water supply". Acta Oecologica 21, n.º 6 (novembro de 2000): 323–36. http://dx.doi.org/10.1016/s1146-609x(00)01084-5.
Texto completo da fonte
34
Cooke, JW. "Effect of fallowing practices on runoff and soil erosion in south-eastern Australia". Australian Journal of Experimental Agriculture 25, n.º 3 (1985): 628. http://dx.doi.org/10.1071/ea9850628.
Texto completo da fonteResumo:
The effect on runoff and soil loss of four methods of preparation of fallow was investigated at each of three sites in north-central Victoria. There was a chemical fallow treatment (uncultivated) and three scarified treatments (smooth, medium and rough cultivation). When the results from the three sites were combined, there was 10.7 mm runoff from the uncultivated treatment, 5.1 mm from the smooth, 0.8 mm from the medium and 0.3 mm from the rough scarified treatments. Soil loss from the uncultivated treatment was 103 g/m2 compared with 87 g/m2 from the smooth, 22 g/m2 from the medium and 13 g/m2 from the rough treatment. The concentration of sediment in the runoff was negatively correlated (R2 = -0.56 to -0.98) with runoff. It ranged from 1.21% (w/w) for the uncultivated to 5.06% (w/w) for the rough scarified treatment. The results show that a regimen of minimum scarification to produce a rough surface, and then use of herbicides to control weeds, reduces soil loss compared with either an uncultivated or a smoothly cultivated soil surface.
35
SPICER, K. W., e P. M. CATLING. "THE BIOLOGY OF CANADIAN WEEDS.: 88. Elodea canadensis Michx." Canadian Journal of Plant Science 68, n.º 4 (1 de outubro de 1988): 1035–51. http://dx.doi.org/10.4141/cjps88-125.
Texto completo da fonteResumo:
A review is provided of information on the biology of elodea (Elodea canadensis Michx.). This submersed aquatic develops dense beds that impede water traffic and restrict water-based recreation in the southern portions of Quebec, Ontario, in British Columbia and Alberta. In some regions the dense beds decrease the efficiency of irrigated agriculture. Native to North America, elodea has recently spread to other parts of the world including Europe, Asia, South Africa, Australia and New Zealand. Elodea is beneficial in providing food and cover for insects and other small aquatic organisms, and consequently it increases food availability for fish and ducks. It also has some potential as a source of food and forage because of its relatively high nutritional content. Elodea is most frequent in clear, nutrient-rich, alkaline water. Phosphorus levels in the plant have been utilized as an indication of trends in the nutrient enrichment of water bodies. Limiting nutrients include bicarbonate and iron. Although seed formation is rare, dispersal of overwintering dormant apices and stem fragments by water and by waterfowl can result in rapid spread. Mechanical controls, including boats equipped with cutters, are the preferred methods of managing elodea, but adequate harvesting of cut material is necessary because every fragment with an axillary or terminal bud may develop into a new plant. Biological control using nonreproductive plant-eating fish is a promising area of research.Key words: Elodea canadensis, weed biology, aquatic, Canada, distribution
36
Rew, L. J., R. W. Medd, R. Van de Ven, J. J. Gavin, G. R. Robinson, M. Tuitee, J. Barnes e S. Walker. "Weed species richness, density and relative abundance on farms in the subtropical grain region of Australia". Australian Journal of Experimental Agriculture 45, n.º 6 (2005): 711. http://dx.doi.org/10.1071/ea03273.
Texto completo da fonteResumo:
Weed management is one of the most important economic and agronomic issues facing farmers in Australia’s grain regions. Weed species occurrence and abundance was monitored between 1997 and 2000 on 46 paddocks (sites) across 18 commercial farms located in the Northern Grain Region. The sites generally fell within 4 disjunct regions, from south to north: Liverpool Plains, Moree, Goondiwindi and Kingaroy. While high species richness was found (139 species or species groups), only 8 species occurred in all 4 regions and many (56 species) only occurred at 1 site or region. No species were observed at every site but 7 species (Sonchus spp., Avena spp., Conyza spp., Echinochloa spp., Convolvulus erubescens, Phalaris spp. and Lactuca serriola) were recorded on more than 70% of sites. The average number of species observed within crops after treatment and before harvest was less than 13. Species richness tended to be higher in winter pulse crops, cotton and in fallows, but overall was similar at the different sampling seasons (summer v. winter). Separate species assemblages associated with the Goondiwindi and Kingaroy regions were identified by correspondence analysis but these appeared to form no logical functional group. The species richness and density was generally low, demonstrating that farmers are managing weed populations effectively in both summer and winter cropping phases. Despite the apparent adoption of conservation tillage, an increase in opportunity cropping and the diversity of crops grown (13) there was no obvious effect of management practices on weed species richness or relative abundance. Avena spp. and Sonchus spp. were 2 of the most dominant weeds, particularly in central and southern latitudes of the region; Amaranthus spp. and Raphanus raphanistrum were the most abundant species in the northern part of the region. The ubiquity of these and other species shows that continued vigilance is required to suppress weeds as a management issue.
37
Braschkat, J., e P. J. Randall. "Excess cation concentrations in shoots and roots of pasture species of importance in south-eastern Australia". Australian Journal of Experimental Agriculture 44, n.º 9 (2004): 883. http://dx.doi.org/10.1071/ea02078.
Texto completo da fonteResumo:
Excess cation concentrations (total cations – total inorganic anions) are reported for roots and shoots of 16 plant species of importance in pastures in south-eastern Australia. This information is required for the calculation of acidification in grazed pasture systems. The excess cation concentrations for shoots at flowering were [cmol(+)/kg]: perennial grasses — Lolium perenne (perennial ryegrass) 50, Phalaris aquatic (phalaris) 51, Danthonia richardsonii (wallaby grass) 30, Dactylus glomerata (cocksfoot) 62, Holcus lanatus (Fog grass) 60; annual grasses — Lolium rigidum 29, Vulpia bromoides (vulpia) 40, Hordeum leporinum (barley grass) 46, Bromus mollis (soft brome) 59; perennial legumes — Medicago sativa (lucerne) 115, Trifolium repens (white clover) 147; annual legumes — Trifolium subterraneum (subterranean clover) 142, Medicago truncatula (barrel medic) 114, Ornithopus sativus (serradella) 137; weeds — Arctotheca calendula (cape weed) 165, Echium plantagineum (Paterson’s curse) 169. Values for roots were in the same order as shoots in vulpia and wallaby grass but lower for the other species, varying between 26 and 62% of the shoot value in grasses and 29 and 49% in legumes. For a subset of 4 legumes and 3 grasses, the excess cation concentrations in shoots were measured over the main production period in spring. Excess cation concentrations generally declined during the season, with the change being relatively larger in grasses than legumes.
38
Ruttledge, Annemieke, Ralph D. B. Whalley, Gregory Falzon, David Backhouse e Brian M. Sindel. "The role of soil temperature and seed dormancy in the creation and maintenance of persistent seed banks of Nassella trichotoma (serrated tussock) on the Northern Tablelands of New South Wales". Rangeland Journal 42, n.º 2 (2020): 85. http://dx.doi.org/10.1071/rj20008.
Texto completo da fonteResumo:
A large and persistent soil seed bank characterises many important grass weeds, including Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock), a major weed in Australia and other countries. In the present study we examined the effects of constant and alternating temperatures in regulating primary and secondary dormancy and the creation and maintenance of its soil seed bank in northern NSW, Australia. One-month-old seeds were stored at 4, 25°C, 40/10°C and 40°C, in a laboratory, and germination tests were conducted every two weeks. Few seeds germinated following storage at 4°C, compared with seeds stored at 25°C, 40/10°C and 40°C. Nylon bags containing freshly harvested seeds were buried among N. trichotoma stands in early summer, and germination tests conducted following exhumation after each season over the next 12 months. Seeds buried over summer and summer plus autumn had higher germination than seeds buried over summer plus autumn plus winter, but germination increased again in the subsequent spring. Seeds stored for zero, three, six and 12 months at laboratory temperatures were placed on a thermogradient plate with 81 temperature combinations, followed by incubation at constant 25°C of un-germinated seeds. Constant high or low temperatures prolonged primary dormancy or induced secondary dormancy whereas alternating temperatures tended to break dormancy. Few temperature combinations resulted in more than 80% germination.
39
Schwinghamer, M. W., J. E. Thomas, M. A. Schilg, J. N. Parry, E. K. Dann, K. J. Moore e S. G. Kumari. "Mastreviruses in chickpea (Cicer arietinum) and other dicotyledonous crops and weeds in Queensland and northern New South Wales, Australia". Australasian Plant Pathology 39, n.º 6 (2010): 551. http://dx.doi.org/10.1071/ap10032.
Texto completo da fonte
40
Warwick, Suzanne I., e Ardath Francis. "The biology of Canadian weeds. 132. Raphanus raphanistrum L." Canadian Journal of Plant Science 85, n.º 3 (1 de julho de 2005): 709–33. http://dx.doi.org/10.4141/p04-120.
Texto completo da fonteResumo:
A review of biological information is provided for Raphanus raphanistrum L. Native to the Mediterranean region, the species is widely introduced and naturalized in temperate regions around the world. In Canada, it currently occurs in all provinces except Saskatchewan and Manitoba, has only a limited distribution in Alberta, and is also absent from the Yukon, the Northwest Territories and Nunavut. It is most abundant in the Atlantic and Pacific regions and is an important weed of field crops in the Maritime provinces and Quebec. A persistent seed bank, competitive annual growth habit and high fecundity all contribute to its weedy nature and ensure that it will be a continuing problem. It can easily hybridize with cultivated radish, R. sativus L., and commonly does so when they occur together. Limited hybridization with canola, Brassica napus L., has been reported from several experimental field and greenhouse trials. Selective herbicide control is most difficult in canola and other cruciferous crops. It is the most important dicot weed in the southwestern region of Australia, primarily due to the evolution of several different herbicide-resistant biotypes. These include biotypes resistant to the acetolactate synthase (ALS)-inhibitors (group 2 herbicides) and/or photosystem II-inhibitors (group 5), and a biotype with multiple resistance to ALS-inhibitors, photosystem II-inhibitors, an auxin (2,4-D amine), and a phytoene desaturase (PSDS)-inhibitor (diflufenican). A biotype resistant to the ALS-inhibiting herbicide chlorsulfuron has also been detected in South Africa. Key words: Wild radish, Raphanus raphanistrum, herbicide resistance, canola, hybridization, RAPRA
41
Hunt, James R. "Winter wheat cultivars in Australian farming systems: a review". Crop and Pasture Science 68, n.º 6 (2017): 501. http://dx.doi.org/10.1071/cp17173.
Texto completo da fonteResumo:
Winter wheat cultivars are defined as those that have an obligate vernalisation requirement that must be met before they will progress from the vegetative to reproductive phase of development i.e. they must experience a true winter before they will flower. Historically, very little breeding effort has been applied to the selection of winter cultivars suited to southern Australia, with the notable exception of the New South Wales Agriculture breeding program based in Wagga and Temora that ran from the 1960s until 2002. A shift by growers to earlier sowing, increased usage of dual-purpose cereals, and research highlighting the whole-farm benefits of winter cultivars to average farm wheat yield has increased grower interest and demand for winter cultivars. Three major wheat breeding companies operating in southern Australia have responded by commencing selection for milling quality winter cultivars, the first of which was released in 2017. Existing research relating to winter wheats in southern Australian farming systems is reviewed here, including interactions with agronomic management, environment and weeds and disease. It is concluded that winter wheats can offer significant production and farming system benefits to growers by allowing earlier establishment, which increases water-limited potential yield (PYw) by ~15% relative to later sown spring wheats, and makes forage available for dual-purpose grazing during vegetative development. Winter wheats sown early require agronomic management different to that of later sown spring wheats, including greater attention to control of grass weeds and certain diseases. There are significant research gaps that will prevent growers from maximising the opportunities from new winter cultivars once they are released. The first of these is a well-defined establishment window for winter cultivars, particularly in medium-low rainfall environments of South Australia, Victoria and Western Australia that have not historically grown them. There is circumstantial evidence that the yield advantage of early established winter wheats over later sown spring wheats is greatest when stored soil water is present at establishment, or the soil profile fills during the growing season. Explicit confirmation of this would allow growers to identify situations where the yield advantage of winter wheats will be maximised. Given the imminent release of several new winter wheat cultivars and the increases in PYw that they embody, it is critical to experimentally define the management and environmental conditions under which performance of these new genotypes are optimised, before their release and availability to growers. Optimising the genotype × environmental × management interactions possible with these cultivars will empower growers to make the best use of the technology and better realise the gains in water limited potential yield possible with these genotypes.
42
Reid, Nick. "Conserving Biodiversity: Threats and Solutions". Pacific Conservation Biology 3, n.º 2 (1997): 166. http://dx.doi.org/10.1071/pc970166.
Texto completo da fonteResumo:
This book records the proceedings of a similarly titled conference organized by the New South Wales National Parks and Wildlife Service in June 1993. According to the editors, the book is a "systematic attempt . . . to cover the current and future threats to biodiversity" in New South Wales and Australia, and "highlights the range of solutions needed to conserve biodiversity". The book contains 35 chapters structured in seven sections (conserving biodiversity, habitat loss, degradation and pollution of water resources, weeds and feral animals, commercial use of native biota, changes to fire regimes, can governments solve the problems?), with two to eight chapters in each. The book is a scientific treatise, chapters being written with other researchers and scientifically trained government officials in mind.
43
Davidson, Bill, Tony Cook e Bhagirath S. Chauhan. "Alternative Options to Glyphosate for Control of Large Echinochloa colona and Chloris virgata Plants in Cropping Fallows". Plants 8, n.º 8 (24 de julho de 2019): 245. http://dx.doi.org/10.3390/plants8080245.
Texto completo da fonteResumo:
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.
44
Brown, Sharon L., Nick Reid, Jackie Reid, Rhiannon Smith, R. D. B. (Wal) Whalley e David Carr. "Topsoil removal and carbon addition for weed control and native grass recruitment in a temperate-derived grassland in northern New South Wales". Rangeland Journal 39, n.º 4 (2017): 355. http://dx.doi.org/10.1071/rj17029.
Texto completo da fonteResumo:
Restoring the grassy understorey to temperate woodlands in south-eastern Australia is often disregarded due to a poor understanding of the techniques involved. The natural recruitment of native grasses is uncommon in the remnants of some of these woodlands, so the restoration of the grass layer is often dependent on interventions to overcome restoration barriers. Soil enrichment from agricultural fertilisers favours the invasion of exotic broadleaf weeds and grasses, and is one of the primary barriers to the successful recruitment and establishment of native grasses, which dominated before agricultural development. This study on the Northern Tablelands of New South Wales investigated the effects of different weed control treatments – scalping, glyphosate (Roundup®) herbicide, and combinations of glyphosate with carbon (sugar and sawdust) addition and a control (nil treatment) recruitment of native grasses and weed emergence after broadcast seeding. The experimental site was a mown grass lawn consisting of fescue (Festuca arundinacea Shreb.), cocksfoot (Dactylis glomerata L.) and paspalum (Paspalum dilatatum Poir). Native grass recruitment varied significantly between treatments. The maximum number of recruits in scalped plots was 29 recruits m–2 compared with an average of <2 recruits m–2 for the glyphosate and glyphosate carbon combinations. Scalping reduced soil nitrogen from 0.6% in non-scalped plots to 0.1% and phosphorus from 191.6 ppm to 40.3 ppm. Maximum weed cover occurred in the glyphosate herbicide treatment (45%), whereas combinations of glyphosate plus either sugar or sawdust maintained weed cover at 13%. The present study suggests that scalping may be a successful intervention strategy because it has the potential to significantly improve native grass recruitment compared with other restoration methods used in this study. Scalping allows more time for native grasses to germinate and establish in the absence of competitive fast-growing exotic weeds.
45
Zahid, Mohammad, Michael Hodda, Geoff Gurr, William Fulkerson, Jackie Nobbs, Alexander Nikandrow e Helen Nicol. "Effect of the clover root-knot nematode (Meloidogyne trifoliophila) on growth of white clover". Nematology 3, n.º 5 (2001): 437–46. http://dx.doi.org/10.1163/156854101753250764.
Texto completo da fonteResumo:
AbstractRoot-infecting nematodes are common on white clover (Trifolium repens) in dairy pastures on the north coast of New South Wales and southeastern Queensland, Australia, where they are thought to contribute to poor growth and persistence. The nematode responsible for causing root-knot symptoms on white clover was identified as Meloidogyne trifoliophila, a species not previously recorded from Australia. M. trifoliophila failed to reproduce on any of the standard North Carolina hosts used to identify M. javanica, M. hapla, M. arenaria and M. incognita , but caused severe galling and exhibited a high rate of reproduction on white clover. PCR primers for these Meloidogyne species also failed to amplify DNA of M. trifoliophila. Identity was confirmed by morphological measurements and plant symptoms. In a glasshouse test, increasing initial nematode density within the range 0 to 10 000 per 500 ml pot led to reduced shoot and root growth, fewer nodules and more severe root-knot symptoms. A second pot test screened weed species as potential alternative hosts of M. trifoliophila. None of the eight grass species was galled but M. trifoliophila reproduced on two of the eight dicotyledon weeds, spear thistle (Cirsium vulgare) and pigweed (Portulaca oleraceae).
46
KNIHINICKI, DANUTA K., KATHRYN L. MCCARREN e JOHN K. SCOTT. "A new species of Aceria (Acari: Eriophyidae) damaging sowthistles, Sonchus spp. (Asteraceae), in Australia with notes on Aceria sonchi (Nalepa, 1902)". Zootaxa 2119, n.º 1 (27 de maio de 2009): 23–38. http://dx.doi.org/10.11646/zootaxa.2119.1.2.
Texto completo da fonteResumo:
A new species of eriophyoid mite from Australia is described and illustrated. Aceria thalgi sp. n. causes severe curling and rolling of leaves of common introduced sowthistle, Sonchus oleraceus L. It also affects introduced Sonchus asper (L.) Hill and native Sonchus hydrophilus Boulos. The native species may be the original host for this mite. Aceria thalgi sp. n. is shown to be a separate species to Aceria sonchi (Nalepa), which forms distinctive leaf galls on Sonchus spp. in southern Europe. English translations of past descriptions of A. sonchi are included for comparison. Historical observations and records from New South Wales suggest that A. thalgi sp. n. has been known for at least 80 years prior to its recent rediscovery in Western Australia. This implies that the newly described species may be widespread across the continent. There is also a past record of similar damage symptoms occurring on sowthistles in New Zealand. Aceria thalgi sp. n. has the potential to be a useful biological control agent in Australia and Canada, where sowthistles are major weeds of agriculture.
47
Midgley, S. J., e J. W. Turnbull. "Domestication and use of Australian acacias: case studies of five important species". Australian Systematic Botany 16, n.º 1 (2003): 89. http://dx.doi.org/10.1071/sb01038.
Texto completo da fonteResumo:
Some Acacia species native to Australia and neighbouring countries are significant in the rural economy of many countries. Aspects of the domestication process and uses of A. mangium, A. crassicarpa, A. mearnsii, A.�saligna and A. colei are reviewed. Commercial plantations of A. mearnsii in tropical highlands and temperate areas provide high quality tannins for adhesives and leather making and wood for paper pulp, rayon, charcoal and small-utility timbers. Plantations of A. saligna in warm-temperate and semi-arid areas provide stock fodder, soil stabilisation, fuelwood and charcoal. In the humid tropical lowlands of South-east Asia, pulpwood is produced in extensive plantings of A. mangium and in smaller-scale plantations of A. crassicarpa in Indonesia. The human food value of seeds of some dry-zone Australian acacias, such as A. colei, is recognised. Domestication of these and other Australian acacias is at various stages and is influenced by the characteristics of the species, extent of planting and the commercial value of the products. The potential for many acacias to become weeds is recognised. The case studies highlight a number of important aspects in domesticating acacias.
48
Scott, John K., e Kathryn L. Batchelor. "Management of Chrysanthemoides monilifera subsp. rotundata in Western Australia". Invasive Plant Science and Management 7, n.º 1 (março de 2014): 190–96. http://dx.doi.org/10.1614/ipsm-d-13-00052.1.
Texto completo da fonteResumo:
AbstractOne of Australia's most serious weeds, Chrysanthemoides monilifera subsp. rotundata (bitou bush) was recently found for the first time in Western Australia as a well established population in Kwinana, a major port and industrial area south of Perth, the State's capital. This population is remote from other bitou bush infestations in Australia and had escaped detection despite extensive surveys in the same State for the other subspecies that is present in Australia, Chrysanthemoides monilifera subsp. monilifera (boneseed). The main reasons it went undetected are thought to be the tightly controlled access to this area because of mineral processing and port activities, the unusual invasion route via a heavy industrial area and the morphological similarity to a native species when it is not flowering. Two surveys defined the core population of 1038 plants that are spread along the coast over a 25-ha semi-circle with about a 500-m (1640 ft) diameter. Subsequent surveys of first a 500 m buffer zone and later a 1-km (0.621 mi) buffer found four additional plants, indicating that there is considerable potential for dispersal. We concluded that the survey has not delimited the distribution because of the potential and evidence for long distance dispersal. Cooperation by the various land managers has led to all plants being killed, as an initial step to management of this species. Other steps to be undertaken include an awareness campaign in the area that would need to be surveyed for delimitation of the spatial distribution and seed bank assessment to measure potential dispersal both in space and through time. It remains to be determined what is the best strategic response: eradication or containment.
49
Duong, Thi Tam, Tom D. Brewer, Jo Luck e Kerstin K. Zander. "Farmers’ assessment of plant biosecurity risk management strategies and influencing factors: A study of smallholder farmers in Australia". Outlook on Agriculture 48, n.º 1 (13 de fevereiro de 2019): 48–57. http://dx.doi.org/10.1177/0030727019829754.
Texto completo da fonteResumo:
Plant biosecurity threats such as pest, weeds and disease occurrences cause substantial economic damage to the agricultural sector, worldwide and in Australia. How smallholder farmers choose biosecurity management strategies remains poorly understood, particularly of smallholder cultural minority groups. In this study, we explore how Vietnamese smallholder farmers in Australia assess their biosecurity risk management strategies and the factors that explain their choice of different strategies. To do so, we conducted a survey of 101 Vietnamese farmers in the Northern Territory, South Australia and Western Australia. Based on the protection motivation theory, we assessed farmers’ perceived self-efficacy, response efficacy and response costs (all elements of their coping appraisal) using descriptive statistics, factor analysis and stepwise regression. Information sources related to biosecurity and farmers’ trust in public management explain how farmers assess their risk management strategies. Previous experience with biosecurity issues does not influence how farmers appraise their biosecurity risk coping capacity. Farmers use four types of biosecurity risk management strategies: chemical control, plant growth strategies, on-farm strategies and asset investment strategies. The first two are the most frequently used. We recommend tailoring relevant government policies to better support farmers’ adoption of risk management strategies based on their specific needs, more investment into biosecurity information dissemination and into trust building.
50
Fleet, Benjamin, e Gurjeet Gill. "Seed Dormancy and Seedling Recruitment in Smooth Barley (Hordeum murinum ssp. glaucum) Populations in Southern Australia". Weed Science 60, n.º 3 (setembro de 2012): 394–400. http://dx.doi.org/10.1614/ws-d-11-00203.1.
Texto completo da fonteResumo:
Weedy barley species have emerged as important weeds in southern Australia, where they can be particularly difficult to control in cereal crops. Knowledge of seed dormancy mechanisms, germination ecology, and recruitment behavior in the field would facilitate development of effective weed-control programs for these weed species. Based on somatic chromosome number, smooth barley was identified as the species infesting all the sites sampled in South Australia. Smooth barley populations from cropping fields and noncrop habitats showed large differences in their pattern of dormancy loss. Noncrop populations (EP2, EP3, and MN2) rapidly lost dormancy during dry after-ripening and showed 70 to 95% germination at 3 mo after maturity. Five populations collected from cropping fields (EP1, EP4, EP5, MN1, and MN3), on the other hand, showed < 30% germination, even at 8 mo after maturity, when germination was assessed at 20/12 C day/night temperatures. These dormant, smooth barley populations from cropping fields were found to be highly responsive to cold stratification, with germination increasing in response to the duration of the treatment. Germination of dormant, smooth barley populations increased with the addition of gibberellic acid (0.001 M GA3), but only when lemma and palea had been removed. Recruitment behavior of smooth barley in the field was influenced by the population and the tillage system. A nondormant population, collected from a long-term pasture (MN2), showed high seedling emergence (> 90%) during autumn, which was well before planting of the winter crop (lentil). In contrast, the other three populations sampled from cropping fields showed very little seedling establishment (< 10%) before crop planting, which would make them difficult to control in cereals because there are no selective herbicides available for the control of weedy barley species. There was a significant seeding system by emergence time interaction (P < 0.001), which was reflected in greater in-crop, smooth barley plant densities under zero-till than under conventional tillage and no-till systems.