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1

Légère, Anne, F. Craig Stevenson, and Diane L. Benoit. "The Selective Memory of Weed Seedbanks after 18 Years of Conservation Tillage." Weed Science 59, no. 1 (March 2011): 98–106. http://dx.doi.org/10.1614/ws-d-10-00092.1.

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A conservation tillage study provided the opportunity to test whether tillage effects on the germinable weed seedbank would be consistent across different crop rotations and to investigate the potential residual effects of herbicide treatments terminated 12 yr earlier. Our objective was to measure the effects of tillage (moldboard plow [MP] vs. chisel plow [CP] vs. no-till [NT]), crop rotation (2-yr barley–red clover followed by 4-yr barley–canola–wheat–soybean rotation, compared to a cereal monoculture), and of a prior weed management factor (three intensity levels of herbicide use) on the density, diversity, and community structure of weed seedbanks. Species richness, evenness (Shannon'sE), and diversity (Shannon'sH′) of spring seedbanks varied little across treatments and over time. Total seedbank density generally increased as tillage was reduced, with some variations due to weed management in 1993 and crop rotation in 2006. Crop rotations generally had smaller seedbanks with fewer species than the monoculture. In 1993, seedbanks with minimum weed management were twice as dense as those with intensive or moderate weed management (approximately 6,000 vs. 3,000 seed m−2). By 2006, seed density averaged 6,838 seed m−2across intensive and moderate weed management regardless of tillage, but was nearly twice as large in NT (12,188 seed m−2) compared to MP (4,770 seed m−2) and CP (7,117 seed m−2) with minimum weed management (LSD0.005= 4488). Species with abundant seedbanks responded differently to treatments. Barnyardgrass and green foxtail had larger seedbanks in the monoculture than in the rotation. Common lambsquarters and pigweed species had large seedbanks in tilled treatments in the rotation, whereas yellow foxtail and field pennycress contributed to the large seedbanks observed in NT treatments. The latter two species were also associated with residual effects of weed management treatments (terminated 12 yr earlier) in NT. The differential seedbank response of weed species, attributed in part to contrasting weed emergence patterns and agronomic practice effects on seed rain, explained some of the weak treatment effects observed for total seedbank density and diversity. The large weed seedbanks observed in NT plots after 18 yr confirms the importance of seed rain and seedbank management for the sustainability of NT systems.
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2

Cavers, Paul B., Marguerite Kane, and James J. O'Toole. "Importance of SeedBanks for Establishment of Newly Introduced Weeds—a Case Study of Proso Millet (Panicum miliaceum)." Weed Science 40, no. 4 (December 1992): 630–35. http://dx.doi.org/10.1017/s0043174500058239.

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Proso millet has become a major weed in North America during the past 20 yr. Experiments were conducted to assess the role of the soil seedbank in proso millet's success as a weed. Proso millet has at least eight distinct biotypes, all weeds, which exhibit a wide range of seedbank behavior. At one extreme, weed biotypes resembling crop varieties form transient seedbanks where all viable seed germinate or die before newly ripened seed enter the seedbank. In contrast, the black- and dark-red-seeded biotypes form persistent seedbanks that last several years in the soil. These latter seedbanks differ from those previously described in that there is always a fraction of the seedbank that is not capable of immediate germination. The black-seeded biotype of proso millet can establish a persistent seedbank quickly and that makes the weed very difficult to eradicate.
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3

Koffi, Kouablan Edmond, Saraka Didier Martial Yao, Nafan Diarrassouba, and Laopé Ambroise Casimir Siene. "Etat Des Lieux Et Gestion Des Semences Des Principales Céréales Cultivées Au Nord De La Côte d’Ivoire." European Scientific Journal, ESJ 13, no. 3 (January 31, 2017): 112. http://dx.doi.org/10.19044/esj.2017.v13n3p112.

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The survey aims at assessing current managing status of organizations involves in the conservation of local genetic diversity of rice, maize, sorghum and pearl millet in seedbanks located in northern Côte d’Ivoire. An investigation was conducted with 100 respondents in charge of cereal seedbanks managing from Ferkessedougou and Ouangolodougou areas. The results at regional scale revealed two co-existing informal and formal systems for seedbanks management in these areas. The farmers’ seedbanks system or informal system was the main source of cereal seed supply for farmers and more important than the national or formal seedbank system. Only, farmers’ seedbanks of two crops, rice and maize were found in visited localities. The management of these farmers’ seedbanks was enabled by associations or cooperatives gathering more men (78.27%) than women (21.73%). Ninety percent (90%) of respondents were identified as saving 1 to 3 traditional varieties of cereal in these seedbanks managed by farmers in the studied region. The reveled difficulties in the farmers’ seedbanks management appeared mainly as informally organized seed system that must be a complementary approach to formal system or national seed system for genetic diversity preservation of local cereal varieties and also as a distribution channel of improved cereal varieties.
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4

McIvor, J. G., I. Saeli, J. J. Hodgkinson, and H. M. Shelton. "Germinable soil seedbanks in native pastures near Crows Nest, south-east Queensland." Rangeland Journal 26, no. 1 (2004): 72. http://dx.doi.org/10.1071/rj04005.

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The soil seedbanks in three patch types (tall grassland, short sward and lawn) were measured in native pastures near Crows Nest, south-east Queensland in two experiments. In the first experiment, seedbanks were measured at four sites, and in the second, the variation in seedbanks during the year was measured at one site. In each experiment the size and composition of the seedbanks were determined by germinating the seeds in soil samples. In the first experiment, total seed numbers ranged from ~6000 to 12,000 per m2. There were no significant differences between sites for total seeds or for seeds of any species group except legumes which comprised only a small portion of the seedbanks. There were significant differences between patch types for total seeds and for the following species groups, medium tussock grasses, short tussock grasses, stoloniferous grasses, legumes and forbs but not large tussock grasses and sedges. Total seed numbers, and those of medium tussock grasses, stoloniferous grasses and forbs were highest in the lawn patches and lowest in the short sward patches. Legumes had higher numbers in the tall grassland patches than in other patch types. In the second experiment, there were large differences between total seed numbers at the different sample dates (January, May, September and November). Numbers were highest in January and then declined throughout the year. This pattern was largely a reflection of the changes in numbers of forb seeds, the species group with the most seeds. There were no significant differences between patch types for total seeds but there were for medium tussock grasses, stoloniferous grasses, sedges and forbs. There was no relationship between the composition of the pasture sward and the composition of the seedbank for any of the three patch types. Twenty-eight species were allocated to persistent and transient seedbank types; all seedbank types occurred in all three patch types. The major species in the seedbanks were sedges (Cyperus gracilis, C. sesquiflorus), forbs (Gamochaeta spp., Paronychia brasiliana, Daucus glochidiatus) and Eragrostis spp.
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5

Young, James A., James D. Trent, Robert R. Blank, and Debra E. Palmquist. "Nitrogen interactions with medusahead (Taeniatherum caput-medusaessp.asperum) seedbanks." Weed Science 46, no. 2 (April 1998): 191–95. http://dx.doi.org/10.1017/s0043174500090408.

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Medusahead is an invasive annual grass that, once established, severely affects range-land productivity and stability. Medusahead builds large seedbanks in the litter and on the soil surface. Effective weed control of medusahead involves either inhibiting germination from the seedbank, eliminating the seedbank, or enhancing germination so that plants are available for control. The purpose of this study was to determine the influence of nitrogen enrichment, immobilization, and nitrification inhibition treatments in the field on the size and germination status of medusahead seedbanks. The germination status of medusahead seeds in seedbanks was determined by periodically collecting field samples of surface soil and litter and bioassaying them in greenhouse emergence tests. Control seedbanks had increased seedling emergence with KNO3or GA3enrichment of the bioassay substrate. The combination of these two materials increased emergence. Nitrogen enrichment increased seedling establishment in the field. Carbon enrichment in the field decreased seedling establishment and increased medusahead seeds in seedbanks. Nitrapyrin treatment decreased medusahead in the field similar to carbon enrichment. In comparison to the control or other treatments, GA3enrichment was not as effective in increasing emergence from nitrapyrin-treated bioassay samples. The combination of carbon and nitrapyrin treatments was very effective in eliminating medusahead emergence in the field, but in wetter years, it never completely eliminated medusahead seedling recruitment and subsequent reproduction. These treatments have promise for influencing succession in medusahead infestations if an adapted perennial species, capable of competing under low nitrogen levels, becomes available.
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6

Cooke, J., J. E. Ash, and R. H. Groves. "Population dynamics of the invasive, annual species, Carrichtera annua, in Australia." Rangeland Journal 34, no. 4 (2012): 375. http://dx.doi.org/10.1071/rj12027.

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Carrichtera annua (L.) DC. (Brassicaceae) is a widespread weed of the southern rangelands of Australia and there is currently no effective control strategy for this weed outside agricultural systems. Field and glasshouse experiments were used to target various stages of the life cycle of C. annua that, from initial field observations and a review of the literature, appeared to be important or were poorly understood in Australia. Seed production was found to be prodigious with up to 30 000 seed m–2 recorded in the field and extensive collection of dry-dispersed seed by ants was documented, similar to that in the native range of C. annua. Two seedbanks, an aerial pod seedbank and a soil seedbank, are key features contributing to the success of this invasive species as the seedbanks are subject to, and protected from, contrasting pressures. The aerial seedbank, usually the larger of the two, protects seed from collection by ants but is susceptible to vertebrate grazing and fire, while the soil seedbank is depleted by ants and seed decay although the adhesive nature of wetted seeds helps stabilise this seedbank. The population can be replenished by either seedbank in one generation, hence both seedbanks need to be targeted to allow successful control. Inhibition of germination by high temperatures in unfavourable conditions and the potential to reach maturation and fruit production very quickly also contribute to the high seed production of this species.
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7

Hazelton, Eric L. G., Rebekah Downard, Karin M. Kettenring, Melissa K. McCormick, and Dennis F. Whigham. "Spatial and Temporal Variation in Brackish Wetland Seedbanks: Implications for Wetland Restoration Following Phragmites Control." Estuaries and Coasts 41, S1 (September 25, 2017): 68–84. http://dx.doi.org/10.1007/s12237-017-0289-z.

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Abstract Chesapeake Bay tidal wetlands are experiencing a broad-scale, aggressive invasion by the non-native, clonal grass Phragmites australis. The grass is often managed with herbicides in efforts to restore native plant communities and wildlife habitat. Management efforts, however, can act as a disturbance, resulting in increased light availability, potentially fostering reinvasion from soil seedbanks. If native vegetation establishes quickly from seedbanks, the site should have greater resiliency against invasion, while disturbed sites where native plants do not rapidly establish may be rapidly colonized by P. australis. We surveyed the soil seedbank of three vegetation cover types in five Chesapeake Bay subestuaries: areas where P. australis had been removed, where P. australis was left intact, and with native, reference vegetation. We determined the total germination, the proportion of the seedbank that was attributable to invasive species, the richness, the functional diversity, and the overall composition of the seedbanks in each of the cover types (i.e., plots). After 2 years of herbicide treatment in the P. australis removal plots, vegetation cover type impacted the total germination or the proportion of invasive species in the seedbank. In contrast, we also found that seedbank functional composition in tidal brackish wetlands was not influenced by vegetation cover type in most cases. Instead, plots within a subestuary had similar seedbank functional composition across the years and were composed of diverse functional groups. Based on these findings, we conclude that plant community recovery following P. australis removal is not seed-limited, and any lack of native vegetation recruitment is likely the result of yet-to-be-determined abiotic factors. These diverse seedbanks could lead to resilient wetland communities that could resist invasions. However, due to the prevalence of undesirable species in the seedbank, passive revegetation following invasive plant removal may speed up their re-establishment. The need for active revegetation will need to be assessed on a case-by-case basis to ensure restoration goals are achieved.
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8

Benoit, Diane L., Douglas A. Derksen, and Bernard Panneton. "Innovative Approaches to Seedbank Studies." Weed Science 40, no. 4 (December 1992): 660–69. http://dx.doi.org/10.1017/s0043174500058276.

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Seedbank studies often suffer from major methodological inadequacies such as absence of appropriate statistical data analysis and low sampling intensity. Multivariate analysis and computer mapping are innovative ways to treat seedbank data. Computer contour mapping was used to visualize spatial patterns of a population of common lambsquarters at three intervals during a growing season. At one site, high spring seed density of 600 000 seed m-2 was decreased to 18.3% of its original size by July, while at another site, low spring seedbank of common lambsquarters of 25 000 seed m-2 increased to 40 000 seed m-2 by autumn. Seedbank studies usually report results on total seed density or on densities of the most abundant species because of difficulties in analyzing large species matrices using parametric statistics. Multivariate analysis and specifically canonical discriminant analysis (CDA) are well suited for seedbank populations. The seedbanks of six agricultural habitats were demonstrated to be floristically different based on the analysis of the relative abundance of weed species in each site using CDA. Organic soils either under grassland or cultivated had significantly larger total seedbanks than mineral soils. If seedbanks are to be used in predictive population models, quantitative data that are reliable, rapidly obtained with limited resources, and logistically feasible for large sampling protocols are needed. Image analysis may be a potential rapid technique for weed seed recognition of washed soil samples.
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9

Schweizer, Edward E., Philip Westra, and Donald W. Lybecker. "Seedbank and Emerged Annual Weed Populations in Cornfields (Zea mays) in Colorado." Weed Technology 12, no. 2 (June 1998): 243–47. http://dx.doi.org/10.1017/s0890037x0004375x.

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Fifty irrigated cornfields in five eastern Colorado counties were sampled for their seedbanks and annual weed seedlings and mature populations between 1988 and 1992. Fourteen annual broadleaf species and seven annual grass species were identified in the 50 seedbanks sampled after the fields were tilled in the fall. Redroot pigweed and a mixture of green and yellow foxtail were the weed species encountered most, occurring in 90 and 54% of the fields, respectively. The single-plant populations of broadleaf and grass species in June and September were similar to those observed in the seedbanks. The number of weed species as seeds in the seedbank, June seedlings, and September plants per field ranged from zero to five grass species and zero to eight broadleaf species.
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10

Lodge, G. M. "Studies of soil seedbanks in native and sown pastures in northern New South Wales." Rangeland Journal 23, no. 2 (2001): 204. http://dx.doi.org/10.1071/rj01007.

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Total and germinable soil seedbanks (litter and soil) were studied for a native pasture and three sown pastures (dominated by Phalaris aquatica L. cv. Sirosa) in northern New South Wales from 1993 to 1996. Soil core samples were taken from continuously grazed plots for both pasture types and two oversown treatments in the native pasture and from a spring-autumn rest treatment at the sown pasture sites. At each site above ground herbage mass was also estimated regularly as part of the Temperate Pasture Sustainability Key Program. For all sites and treatments, the proportion of germinable seeds as a percentage of the total (dormant and germinable) seedbank ranged from 1–26% for the native pasture and 1–39% for the sown pastures. Germinable seed numbers ranged from 280 to 26,110 seeds per m2, while total seedbank numbers were from 6700 to 178,360 seeds per m2. Native pasture herbage mass was dominated by native perennial grasses, but seeds of these species were less than 20% of the total seed bank in all treatments in 1994 and 1995. At the sown pasture sites, most of the germinable (51–92%) and total (65–97%) seedbanks were either barnyard grass (Echinochloa crus-galli (L.) Beauv, annual ryegrass (Lolium rigidum Gaudin), subterranean clover (Trifolium subterraneum L.) or wireweed (Polygonum aviculare L.). Since seeds of annuals and other forbs generally dominated both the total and germinable seedbanks of these perennial grass-based pastures, these species were likely to increase over time. Seeds of the sown perennial grass Phalaris aquatica L, cv. Sirosa were less than 1% of the total seedbanks in pastures sown in 1990 and less than 3% of those sown in 1979. With above average summer rainfall at the native pasture site in 1996 and prolific growth of redgrass, seeds of this species were 38–63% of the total and 11–29% of the germinable seedbank in May 1996. Except at this site and time, the species composition of the total and germinable seedbanks did not generally reflect the dominance of the above ground herbage mass of these pastures by perennial grasses.
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11

Venn, Susanna E., and John W. Morgan. "Soil seedbank composition and dynamics across alpine summits in south-eastern Australia." Australian Journal of Botany 58, no. 5 (2010): 349. http://dx.doi.org/10.1071/bt10058.

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Alpine soil seedbanks are generally regarded as small and unimportant to regeneration. Here, we investigate for the first time the composition of the readily germinable soil seedbank across alpine summits in south-eastern Australia. We aimed to compare the species in the seedbank with the standing vegetation, show seasonal variations in seedbank composition and identify regeneration strategies of alpine seedbank species. By using standard glasshouse and cold-stratification germination techniques, the germinable soil seedbank across the study region was found to comprise 39 species from 25 families, with species from the Asteraceae the most common. Persistent seedbanks were found across all eight alpine summits (1668–1970 m), comparable in seed density (150 ± 27 to 1330 ± 294 per m2) with those of other alpine areas in the northern and southern hemispheres. The density of germinable seeds varied widely among sites and between collection times (autumn, spring) and there were no trends in seed density with altitude. The qualitative and quantitative similarity between the seedbank species and the standing vegetation was low. Correlations between the proportions of species in regeneration categories (from obligate seeders, through to vegetative regenerators) in the standing vegetation and the seedbank were also poor. Our results indicate a divergence between the species in the current standing vegetation and those present in the readily germinable soil seed bank. The current patterns and predominance of seed-regenerating species in the seedbank indicate that these species may have an important role to play in regulating and contributing to future changes in the vegetation assemblage.
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12

Légère, Anne, F. Craig Stevenson, Diane Lyse Benoit, and Nathalie Samson. "Seedbank–plant relationships for 19 weed taxa in spring barley–red clover cropping systems." Weed Science 53, no. 5 (October 2005): 640–50. http://dx.doi.org/10.1614/ws-04-146r.1.

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The objective of this study was to examine the effects of crop rotation (spring barley monoculture vs. spring barley–red clover 2-yr rotation), tillage (moldboard plow, chisel plow, no-till), and weed management (intensive, moderate, minimum) on plant–seedbank relationships for 19 weed species. Plant and seedbank density data were collected over 4 yr and analyzed by analysis of variance and correlation analysis to confirm treatment effects on plant–seedbank relationships. The relative frequency (difference between aboveground and seedbank frequency) of many species was more influenced by rotation, whereas species density appeared regulated more by weed management than by other factors. Frequency data confirmed that very few species were ubiquitous over time or treatment, aboveground or in the seedbank. The perennial species, field horsetail, quackgrass, white clover, and perennial sowthistle were more frequent aboveground than in the seedbank. This was also observed for annuals such as common hempnettle, sun spurge, catchweed bedstraw, and annual grasses. Treatment effects on abundance were inconsistent aboveground and in the seedbank across time for 12 of 19 species. The seven species that showed more consistent treatment response for abundance were frequent species present in 50% of the plots both aboveground and in the seedbank. For most species, plant density was correlated with either the previous or current year seedbank, but correlations were rarely of the same magnitude and significance over the years. Common chickweed was the only species for which treatment effects on the plant–seedbank relationship were confirmed for all 4 yr. Correlations between midseason plant populations and subsequent seedbanks confirmed the role of residual populations in replenishing the seedbanks, including those of perennials like quackgrass and dandelion. Overall, plant–seedbank relationships were tenuous for many weed species and varied over time with cropping practices and environment.
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13

Bagavathiannan, Muthukumar V., Jason K. Norsworthy, Kenneth L. Smith, and Nilda Burgos. "Seedbank Size and Emergence Pattern of Barnyardgrass (Echinochloa crus-galli) in Arkansas." Weed Science 59, no. 3 (September 2011): 359–65. http://dx.doi.org/10.1614/ws-d-10-00149.1.

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Barnyardgrass is one of the most problematic weeds in Arkansas, and with the documentation of herbicide-resistant biotypes, there is a need to gain a detailed understanding of its ecology. In particular, knowledge on barnyardgrass seedbank size and emergence pattern is vital. An extensive seedbank survey was carried out in 2008 in 12 counties in eastern Arkansas to determine barnyardgrass seedbank size across the region. There was a great variability in seedbank size with a maximum of 215,000 seeds m−2. Among the fields surveyed, barnyardgrass seedbank was found only in 7% of the cotton fields, while it was 22 and 20%, respectively, for rice and soybean. To examine the emergence pattern of barnyardgrass, experiments were conducted in Rohwer (two sites), Stuttgart (one site), and Fayetteville (one site), Arkansas in 2008 and 2009. In each site, barnyardgrass emergence was quantified from naturally occurring seedbanks. Barnyardgrass exhibited an extended period of emergence with days to 100% emergence ranging from 99 to 165 across sites and years. Nevertheless, effective management may be achieved by targeting the peak emergence periods, which range from mid-April to mid-June in Arkansas. The four-parameter Weibull model provided a better fit to the cumulative emergence data. However, the thermal time (growing degree days, GDDs) or hydrothermal time (HTT) models did not predict barnyardgrass emergence any better than calendar days, perhaps because of the inherent variations associated with natural seedbanks. This study establishes seedbank size and general emergence pattern for barnyardgrass in Arkansas. Additionally, these results will be useful for parameterizing herbicide-resistance simulation models for barnyardgrass.
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14

Schutte, Brian J., Nina Klypin, and Manoj K. Shukla. "Influence of Irrigation Timing on Disturbance-Induced Reductions in Soil Seedbank Density." Weed Science 64, no. 4 (December 2016): 613–23. http://dx.doi.org/10.1614/ws-d-15-00191.1.

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Studies suggest that disturbance-induced reductions in soil seedbank density are diminished by periods of water scarcity after soil disturbance; however, this hypothesis has yet to be tested. The objectives of this study were (1) to determine the effects of increasing time between soil disturbance and flood irrigation on disturbance-induced reductions in soil seedbank density, and (2) to identify specific soil moisture levels that cause seedbank reductions under flood irrigation. Weed species in this study were junglerice, Palmer amaranth, and yellow foxtail. For Objective 1, artificial seedbanks with known numbers of seeds were disturbed 10, 3, or 0 d prior to flood irrigations under field conditions. For Objective 2, seeds were buried in soil mesocosms that were hydrated to specific soil water potentials (flooded, 0 kPa, −30 kPa, −60 kPa, and −180 kPa) and placed in laboratory conditions favorable for germination. For both objectives, seeds were recovered to determine the percentages of buried seeds that survived the disturbance or moisture treatments. Results for the field study indicated that soil disturbances reduced seedbank persistence of Palmer amaranth but did not affect seedbank persistence of junglerice and yellow foxtail. Disturbance-induced reductions in seedbank density were greatest when soil was disturbed 0 and 3 d prior to flood irrigations. For the laboratory study, results showed that waterlogged soil was not required for seedbank losses because rates of seedbank persistence were greater in saturated soils (0 kPa and flooded) compared to the lower moisture levels. These studies indicate that delays in irrigation can reduce the seedbank reduction potentials of soil disturbance events. Further, irrigation timing effects on disturbed soil seedbanks are likely to occur in all irrigation systems, including those that reduce the amount of water applied compared to flood irrigation.
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15

White, Scott N. "Evaluation of herbicides for hair fescue (Festuca filiformis) management and potential seedbank reduction in lowbush blueberry." Weed Technology 33, no. 6 (August 29, 2019): 840–46. http://dx.doi.org/10.1017/wet.2019.71.

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AbstractHair fescue is a widespread, seed-limited perennial grass in lowbush blueberry fields. Growers rely on pronamide, an expensive and difficult herbicide to use, for hair fescue management. Recent herbicide registrations provide opportunity to reduce pronamide use, though effects of these herbicides on hair fescue suppression and seedbank reduction are not well understood. The objectives of this research were to determine (1) the effects of herbicides currently registered in lowbush blueberry on suppression of hair fescue tufts and (2) whether suppression of hair fescue with these herbicides reduces hair fescue seedbanks. Pronamide gave the most consistent reductions in flowering tuft density, though applications after both autumn pruning and autumn of the nonbearing year were required to reduce the hair fescue seedbank by >60% across sites. Nonbearing-year hexazinone applications did not control hair fescue or reduce the seedbank. Nonbearing-year terbacil applications reduced flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. Glufosinate applications following autumn pruning or in the spring of the nonbearing year did not suppress hair fescue or reduce the seedbank. Spring nonbearing-year foramsulfuron applications, alone or after autumn or spring glufosinate applications, reduced hair fescue flowering tuft density, but hair fescue recovered in the bearing year, and the seedbank was not reduced. In contrast, autumn and spring glufosinate applications followed by spring nonbearing-year foramsulfuron applications, when combined with autumn nonbearing-year pronamide applications, reduced flowering tuft density in both the nonbearing and bearing years and reduced the hair fescue seedbank by 58% to 83% across sites. Results indicate that hair fescue seedbanks can be reduced in lowbush blueberry fields and that a reduction in pronamide use will require alternative bearing-year treatments to prevent tuft recovery and seed production.
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16

Schutte, Brian J. "Measuring Interference from Midseason Tall Morningglory (Ipomoea purpurea) to Develop a Model for Teaching Weed Seedbank Effects on Chile Pepper." Weed Technology 31, no. 1 (January 2017): 155–64. http://dx.doi.org/10.1017/wet.2016.19.

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Tactics that target seedbanks are important components of weed management systems; however, such tactics can be difficult to adopt because consequences of seedbank reduction are often unclear. This study developed model-based software to provide insights on the economic outcomes, in the context of chile pepper production, of additions to tall morningglory seedbanks. Data for the model were derived from this and previous studies. In this study, field experiments were conducted to determine chile pepper yield and harvest efficiency responses to mid-season tall morningglory infestations. The experimental treatments were factorial combinations of herbicide (pendimethalin-treated, nontreated) and tall morningglory density (0, 4, 8, 12, 16, 20 plants 10-m row–1). Treatments were installed 9.5 weeks after crop seeding. Data collected included fresh weight of marketable chile peppers and time required for one individual to harvest 10-m of crop row, which was used to calculate the amount of chile pepper harvested in 1 min (harvest efficiency). Results indicated that crop yield was not influenced by tall morningglory density, pendimethalin treatment and interactions between tall morningglory density and pendimethalin. Harvest efficiency was influenced by tall morningglory density but was not influenced by herbicide treatment or interactions between herbicide treatment and tall morningglory density. Each additional tall morningglory plant decreased the amount of chile pepper harvested in 1 min by 9.7 g. The results of this and previous studies were used to develop model-based software that presents tall morningglory seedbank density effects on: (1) tall morningglory seedling densities after pendimethalin, (2) time requirements for hand-hoeing after pendimethalin, and (3) time requirements for hand-harvesting to acquire yield goals. The model-based software is intended to be used in the instruction of weed seedbank management strategies. By presenting seedbank density effects on weed control outcomes and crop production expenses, the model-based software might promote adoption of seedbank reduction strategies.
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Khanghahi, Mohammad Yaghoubi, Hemmatollah Pirdashti, Mohsen Mohseni‑Moghadam, and Raheleh Roham. "Vertical Distribution of Nutsedge (Cyperus spp. L.) and Bahiagrass (Paspalum notatum L.) Seed Bank in Rice Growth Cycle." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 67, no. 3 (2019): 787–95. http://dx.doi.org/10.11118/actaun201967030787.

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Weed management in rice continues to be a major challenge to the success of rice growers in northern Iran. Field experiments were conducted at Sari Agricultural Sciences and Natural Resources University to investigate the spatial distribution of weed seeds in the rice growth cycle in 2010 and 2011. Transplanting was done on June 6 in both years. Samples for seedbank analysis were collected 10 days before transplanting and emerged weed density was determined on three different dates during the growing season. Results indicated that nutsedge (Cyperusspp) and bahiagrass (Paspalum notatum) were the two most abundant weed species. The vertical distribution of weed seeds decreased by depth from 0.1 to 0.3 m, while weed pressure was the highest at the 0–0.1 m soil depth. There was no relationship between soil weed seedbanks (at different depths) and emerged weed populations, suggesting that weed seedbank data are not good predictors of weed seedling densities. Nevertheless, Kriging maps indicated that the spatial distribution of weed seeds was in accordance with seedling germination pattern. Also the regression coefficient for 0–0.1 m soil depth was R2= 0.17 and R2= 0.34 for relation between nutsedge and bahiagrass seedlings and their seedbank in 2010 and also, R2= 0.18 and R2= 0.05 in 2011, respectively. Therefore, results achieved from this depth can be used to predict the relationship between nutsedge and bahiagrass seedlings densities and weed seedbanks. The results of this study provide an option for the farmers growing rice to understand the dynamics of weed populations in a cost effective way.
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Rahman, A., T. K. James, J. Mellsop, and N. Grbavac. "Weed seedbank dynamics in maize under different herbicide regimes." New Zealand Plant Protection 54 (August 1, 2001): 168–73. http://dx.doi.org/10.30843/nzpp.2001.54.3716.

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The influence of different herbicide regimes on the size and composition of the soil weed seedbank in maize was studied over three years Preemergence atrazine alachlor atrazine alachlor or no herbicide treatments were imposed on the same plots each year Soil samples to 100 mm depth were collected each autumn and spring and the seedbank was estimated by seed extraction and seedling emergence Data showed strong positive correlation between the two methods Soil seedbank increased dramatically by each autumn but declined by spring The total seedbank increased over three years in the no herbicide treatment Good weed control by atrazine alachlor kept seedbank density at low levels However seed numbers increased particularly in the first two years with only partial weed control using atrazine or alachlor singly A sharp increase of fathen (Chenopodium album) seeds illustrated the danger of building seedbanks of weeds which become tolerant to the strategies used
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19

Davis, Adam S., Brian J. Schutte, James Iannuzzi, and Karen A. Renner. "Chemical and Physical Defense of Weed Seeds in Relation to Soil Seedbank Persistence." Weed Science 56, no. 5 (October 2008): 676–84. http://dx.doi.org/10.1614/ws-07-196.1.

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Effective weed seedbank management requires mechanistic understanding of ecological determinants of seed persistence in the soil seedbank. Chemical and physical defense of common lambsquarters, field pennycress, giant foxtail, kochia, velvetleaf, and yellow foxtail seeds were quantified in relation to short- and long-term seedbank persistence. Seed content ofortho-dihydroxyphenols (o-DHP), a class of putative seed defense compounds, varied more than threefold between the least protected species (common lambsquarters, 9.2 µg g seed−1) and the most protected species (kochia, 34.1 µg g seed−1). Seedo-DHP was inversely related (r= −0.77, P < 0.001) to seed half-life in the soil and to short-term seed persistence in burial assays (r= −0.82, P < 0.05). The relative importance of chemical seed protection in comparison to physical seed protection, as represented by the ratio of seedo-DHP concentration to seed coat thickness, decreased linearly with increasing short-term seed persistence (r= −0.96, P < 0.01) and nonlinearly with increasing long-term seed persistence in the soil seedbank (y = 0.16 + 0.21/(0.0432 + x),R2= 0.99, P < 0.001). Mechanical damage to the seed coat, via piercing, slicing, or grinding treatments, increased short-term mortality during burial for all six species. Mortality of pierced seeds was negatively associated (r= −0.35, P < 0.05) with seed phenol concentration and positively associated with seed half-life (r= 0.42, P < 0.01) and seed coat thickness (r= 0.36, P < 0.05). Seed phenolics, as a class, supported the results foro-DHPs. Overall, these findings suggest a potential weakness, with respect to seedbank management, in the way weed seed defenses are constructed. Weed species with transient seedbanks appear to invest more in chemical defense than those species with highly persistent seedbanks. As a result, seeds in the latter category are relatively more dependent upon physical seed protection for persistence in the soil seedbank, and more vulnerable to management tactics that reduce the physical integrity of the weed seed coat.
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Smith, Richard G., Sonja K. Birthisel, Sidney C. Bosworth, Bryan Brown, Thomas M. Davis, Eric R. Gallandt, Ann Hazelrigg, Eric Venturini, and Nicholas D. Warren. "Environmental Correlates with Germinable Weed Seedbanks on Organic Farms across Northern New England." Weed Science 66, no. 1 (August 24, 2017): 78–93. http://dx.doi.org/10.1017/wsc.2017.40.

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The northern New England region includes the states of Vermont, New Hampshire, and Maine and encompasses a large degree of climate and edaphic variation across a relatively small spatial area, making it ideal for studying climate change impacts on agricultural weed communities. We sampled weed seedbanks and measured soil physical and chemical characteristics on 77 organic farms across the region and analyzed the relationships between weed community parameters and select geographic, climatic, and edaphic variables using multivariate procedures. Temperature-related variables (latitude, longitude, mean maximum and minimum temperature) were the strongest and most consistent correlates with weed seedbank composition. Edaphic variables were, for the most part, relatively weaker and inconsistent correlates with weed seedbanks. Our analyses also indicate that a number of agriculturally important weed species are associated with specific U.S. Department of Agriculture plant hardiness zones, implying that future changes in climate factors that result in geographic shifts in these zones will likely be accompanied by changes in the composition of weed communities and therefore new management challenges for farmers.
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21

Firbank, L. G., P. Rothery, M. J. May, S. J. Clark, R. J. Scott, R. C. Stuart, C. W. H. Boffey, et al. "Effects of genetically modified herbicide-tolerant cropping systems on weed seedbanks in two years of following crops." Biology Letters 2, no. 1 (September 27, 2005): 140–43. http://dx.doi.org/10.1098/rsbl.2005.0390.

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The Farm Scale Evaluations (FSEs) showed that genetically modified herbicide-tolerant (GMHT) cropping systems could influence farmland biodiversity because of their effects on weed biomass and seed production. Recently published results for winter oilseed rape showed that a switch to GMHT crops significantly affected weed seedbanks for at least 2 years after the crops were sown, potentially causing longer-term effects on other taxa. Here, we seek evidence for similar medium-term effects on weed seedbanks following spring-sown GMHT crops, using newly available data from the FSEs. Weed seedbanks following GMHT maize were significantly higher than following conventional varieties for both the first and second years, while by contrast, seedbanks following GMHT spring oilseed rape were significantly lower over this period. Seedbanks following GMHT beet were smaller than following conventional crops in the first year after the crops had been sown, but this difference was much reduced by the second year for reasons that are not clear. These new data provide important empirical evidence for longer-term effects of GMHT cropping on farmland biodiversity.
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22

A. Offord, C., M. L. McKensy, and P. V. Cuneo. "Critical review of threatened species collections in the New South Wales Seedbank: implications for ex situ conservation of biodiversity." Pacific Conservation Biology 10, no. 4 (2004): 221. http://dx.doi.org/10.1071/pc040221.

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This article reviews the germinability and viability of seeds of threatened species collections in the New South Wales (NSW) Seedbank with the manifold aims of: ensuring that existing storage treatments and conditions provide effective ex situ storage of threatened species seed; providing baseline viability and seed storage life data on threatened species; and, identifying research gaps in seed germination and storage protocols for threatened species and communities. The germinability and viability of a range of seed accessions, of various ages and stored under different (although mainly identifiable) conditions in the NSW Seedbank, was determined through germination and cut-tests. The results indicated that many of the Fabaceae, Myrtaceae and Proteaceae species tested are orthodox and can be stored at 5 to 10% moisture content at 5�C for up to ten years without significant loss of viability (short- to medium-term storage). The best results were obtained in the lower seed moisture content range (2 to 9%), which appeared to be especially critical for long-term storage of many Proteaceae accessions, reinforcing the need to attain the correct seed moisture content for long-term storage. Around 10% of accessions exhibited some degree of dormancy even after long storage periods. Storage of the widest range of species, for periods greater than ten years for long-term conservation purposes, is generally best conducted by storing at sub-zero temperatures. Freezing at -18�C had little effect on the germinability of a range of seeds tested and is recommended over storage at 5�C. Collection and seed banking procedures for the NSW Seedbank will be regularly reviewed and procedures modified in order to identify the best long-term storage conditions for species within this and other seedbanks. Seed collection strategies to maximize diversity and uses of seedbanks in conservation are discussed.
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23

Robyn, Adele, Gail M. Littlejohn, and Henry Allies. "SEEDBANKS OF SOUTHERN AFRICAN PROTEACEAE." Acta Horticulturae, no. 545 (February 2001): 29–33. http://dx.doi.org/10.17660/actahortic.2001.545.2.

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Schutte, Brian J., and Ashley Cunningham. "Tall Morningglory (Ipomoea purpurea) Seedbank Density Effects on Pendimethalin Control Outcomes." Weed Technology 29, no. 4 (December 2015): 844–53. http://dx.doi.org/10.1614/wt-d-14-00161.1.

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Pendimethalin control failures on tall morningglory are critical shortcomings in weed-control programs for chile pepper in New Mexico. Using weed seedbank augmentation, we conducted a field study to (1) determine if pendimethalin control of tall morningglory is affected by tall morningglory seedbank density, and (2) identify weed community factors that influence labor for removing the tall morningglory plants that escape pendimethalin. The field study was complemented with a growth chamber study conducted to clarify the effects of pendimethalin rate on the putative association between tall morningglory seedbank density and pendimethalin control outcomes. Under field conditions and after square-root transformation of the dependent variable, the effects of seedbank density on seedling escape density were described with natural logarithmic functions. Although pendimethalin control of tall morningglory decreased with increasing seedbank density, seedbank additions increased labor requirements for removing tall morningglory at only a site-year characterized by low population densities in the indigenous weed community. In growth chambers, increasing pendimethalin rate negatively influenced the effects of increasing seedbank density on pendimethalin control failures. This study shows that pendimethalin control of tall morningglory is reduced when seedbank densities of this species are high. Knowledge of seedbank density effects on specific control outcomes may influence grower attitudes on management strategies that target weed seedbanks.
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25

Bhowmik, Prasanta C. "Weed biology: importance to weed management." Weed Science 45, no. 3 (June 1997): 349–56. http://dx.doi.org/10.1017/s0043174500092973.

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Knowledge of weed biology is essential for development of both economically and environmentally acceptable weed management systems. Weed biology relates to plant attributes such as morphology, seed dormancy and germination, physiology of growth, competitive ability, and reproductive biology. Concepts of population biology such as seedbank dynamics for annuals and root reserves, dormancy, and longevity of vegetative propagules for perennials can be used to predict weed infestations better and to evaluate sustainable management strategies. Integrated approaches that give priority to depletion of root reserves or seedbanks through interfering with dormancy or germination requirements have great potential to enhance weed management strategies in the future.
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26

Chick, Matthew P., Janet S. Cohn, Craig R. Nitschke, and Alan York. "Lack of soil seedbank change with time since fire: relevance to seed supply after prescribed burns." International Journal of Wildland Fire 25, no. 8 (2016): 849. http://dx.doi.org/10.1071/wf15013.

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Soil seedbanks play a key role in the post-fire recruitment of many plant species. Seedbank diversity can be influenced by spatial variability (e.g. geographic location), environmental variability (e.g. soils) and temporal disturbance heterogeneity (e.g. time since fire, TSF) across the landscape. Unlike for aboveground vegetation, relationships between these factors and soil seedbank diversity remain largely unknown. Partitioning the influence of spatial and environmental variability from that of TSF, and explaining how these factors interact with seedbank diversity, will assist conservation managers in their application of prescribed burning. We germinated soil seedbank samples from sites ranging from 1 to 75 years since fire in a heathy-woodland ecosystem across the Otway Ranges in Victoria, Australia. We also measured spatial and environmental variability across sites to partition the influence of these variables and TSF on propagules available for recruitment. We found weak positive relationships between seedbank richness and TSF; however, these relationships varied across the landscape. We found composition did not change considerably over time, suggesting, in this ecosystem, pre-fire age is not strongly influencing propagules available for recruitment post-fire. Our results suggest that spatial and environmental variability influence seedbank composition more than TSF.
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Forcella, Frank, Robert G. Wilson, Karen A. Renner, Jack Dekker, Robert G. Harvey, David A. Alm, Douglas D. Buhler, and John Cardina. "Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application." Weed Science 40, no. 4 (December 1992): 636–44. http://dx.doi.org/10.1017/s0043174500058240.

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Seedbanks and seedling emergence of annual weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m-2among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when < 10 cores were examined per plot, but stabilized at all locations when ≥ 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from < 1% for yellow rocket to 30% for giant foxtail. Redroot pigweed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for weed control.
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28

Jordan, Nicholas. "Simulation Analysis of Weed Population Dynamics in Ridge-Tilled fields." Weed Science 41, no. 3 (September 1993): 468–74. http://dx.doi.org/10.1017/s0043174500052206.

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Effects of nonchemical weed control on weed and seedbank demography in ridge-tilled fields were simulated to examine long-term effects on weed population dynamics. Ridge tillage entails active seedbank management, including removal of much of the seedbank from the crop growth zone (ridge) to the interridge zone (furrow) at planting, and other seedbank manipulations. Dynamics of simulated yellow foxtail and velvetleaf populations were sharply sensitive to the rate of seed removal from the ridge. Variation in winter seed survival, ridge plant demography (emergence, survival, and seed production), and seed survival in the furrow after removal from the ridge also had strong effects on simulated dynamics. To prevent rapid population growth in a simulated corn-soybean rotation, very effective control of seedlings emerging with each crop was necessary to offset seed production from seedlings emerging after ridge rebuilding in corn years. Dynamics of both species were highly sensitive to cultivation efficiency. Effective “rescue” weed control must be available to prevent sharp increases in weed seedbanks during years when cultivation is ineffective.
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29

Callister, Kate E., Singarayer K. Florentine, and Martin E. Westbrooke. "An investigation of the soil seedbank and seed germination of perennial species in Belah (Casuarina pauper) woodlands in north-west Victoria." Australian Journal of Botany 66, no. 3 (2018): 202. http://dx.doi.org/10.1071/bt17160.

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Semiarid and arid woodlands across much of southern Australia have been subject to prolonged high total grazing pressure leading to loss of species diversity and a lack of recruitment of long-lived perennial species. Regeneration of perennial species requires grazing pressure to be maintained at low levels, but gaps remain in our ecological understanding of regeneration potential. The present study investigated the abundance of germinable seed in the soil seedbank in high quality remnants of Casuarina pauper F.Muell. ex L.A.S.Johnson (Belah) woodlands in north-west Victoria. Seed viability and response to six seed pretreatments including dry heat, wet heat, smoky water, soaking in distilled water, cold stratification and sand scarification were also tested to determine whether seed factors may be limiting regeneration. Results suggest that seed viability was not a limiting regeneration factor for nine out of the 10 perennial species tested with the exception of Alectryon oleifolius S.T. Reynolds. Only small amounts of seed from perennial species, largely Chenopodiaceae species and C. pauper, were found in the soil seedbanks of intact sites, suggesting component perennial species do not maintain long-term soil seedbanks. Results suggest that natural recovery of perennial species diversity in depauperate sites will depend on seed dispersal.
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30

Grace, B. S., A. W. Sheppard, R. D. B. Whalley, and B. M. Sindel. "Seedbanks and seedling emergence of saffron thistle (Carthamus lanatus) in eastern Australian pastures." Australian Journal of Agricultural Research 53, no. 12 (2002): 1327. http://dx.doi.org/10.1071/ar02030.

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Weed management has often proved difficult because of persistent seedbanks that allow recruitment to occur for many years after the weed has otherwise been controlled. The number of seeds in seedbanks of Carthamus lanatus, a widespread and troublesome weed, has not been investigated. Little is known about longevity of its seedbanks in pastures of eastern Australia.The numbers of seeds in the soil and the rate of seed loss were investigated at 3 sites in eastern Australia. Seedbanks were found to be patchy, and they had mean densities between 815 and 2290 seeds/m2 after the main germination flush. These seedbanks decreased over time and between 11 and 15% of seeds remained in the soil after 2 years without further input. More seeds were lost in the first year than in the second year, and pasture cover did not affect the rate of seed loss.Seeds buried in mesh bags and exhumed regularly showed that dormancy was lost, induced, then lost again within the 2-year experiment. Maximum seed germinability coincided with peak germination times. The likelihood of a seed producing a seedling was reduced when seeds were sown at high density. C. lanatus seeds appear to be well adapted for persistence in eastern Australian pastures by maintaining a bank of seeds that generally germinate when conditions favour seedling survival.
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31

Osca, José M., Felip Galán, and Héctor Moreno-Ramón. "Rice Paddy Soil Seedbanks Composition in a Mediterranean Wetland and the Influence of Winter Flooding." Agronomy 11, no. 6 (June 12, 2021): 1199. http://dx.doi.org/10.3390/agronomy11061199.

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Soil seedbanks are defined in composition and quantity by many environmental factors inherent to a specific area, and they can be an indicator of the potential problems of weeds in crops. In Valencia (Spain), rice is cultivated with continuous flooding during the growing season, and after harvesting, many of the paddy fields are flooded again during the winter. This study investigates the paddy fields’ soil seedbank composition in this Mediterranean paddy area and the effect of winter flooding on the soil seedbank. Multispectral images from the Sentinel-2 satellite were used to characterise the water level of paddies in winter. Satellite images facilitated the characterisation of winter flooding in fields. Soil samples from sixty-nine points distributed over 15,000 ha of paddies were used to determine the composition of the seedbank plots. The data were spatially represented by geographic information systems. The species that contributed most to the paddy seedbank were Cyperus difformis L., an important rice weed in the Mediterranean area, and other rice weeds such as Echinochloa sp. and Leptochloa fusca subspecies. Other species with a great contribution to the seedbank are species that develop in paddy fields that produce a large quantity of small seeds, such as Lemna sp., Polypogon monspeliensis (L.) Desf., and Nasturtium officinale R. Br. These species interfere little or do not interfere with the rice crop. The study revealed that in general, flooding reduced seedbank density with differences between species. Furthermore, the influence of winter flooding on the different plant species obtained as well as their distribution maps are a further step in this protected area from the point of view of weed management in rice crop, as well as in the management of this Mediterranean wetland.
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32

Koch, John M., Alex M. Ruschmann, and Tim K. Morald. "Effect of time since burn on soil seedbanks in the jarrah forest of Western Australia." Australian Journal of Botany 57, no. 8 (2009): 647. http://dx.doi.org/10.1071/bt09101.

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Bauxite is mined in the jarrah (Eucalyptus marginata Sm.) forest of south-western Australia and 700–800 ha each year are rehabilitated by mining companies. As well as broadcasting seeds and planting, the mine restoration relies heavily on the natural soil seedbank as a means of reinstating plant diversity after mining. The natural soil seedbank is a large but highly variable resource, both spatially and temporally. In the present study, we used 32 sites paired across burn boundaries to determine changes in soil seedbanks due to time since burn. At each site, we took one hundred 100-cm2 soil samples down to 5-cm depth and recorded germinable seeds. The mean total seedbank over all sites was 472 seeds m–2 (90–1210 seeds m–2). Five months after a spring burn, there was a significant decrease in the seedbank of legumes, compared with unburnt sites, probably due to germination in spring immediately after burning. Non-legumes (mostly non-heat-responsive species) did not show this decrease. One year after burning, there was a significant reduction in the total seedbank, presumably due to germination of most species in the winter following the burn. Legumes and non-legumes both showed this decrease. There was a recovery of the soil seedbank by 3 years after burning. This recovery was associated with higher densities of species from the families Apiaceae, Rhamnaceae (Trymalium ledifolium Fenzl), Stylidiaceae, Rutaceae, Centrolepidaceae and Sterculiaceae (Lasiopetalum floribundum Benth.). These families represent annuals, herbaceous species and small perennial shrubs. The recovery was likely due to vigorous flowering, and seed set by seedlings and sometimes resprouts following the burn. Once recovered, the soil seedbank stayed reasonably consistent up to 22 years after burning. Soils stripped 1 year after burning may contribute less plant density and diversity to rehabilitated areas. There is no evidence that the soil seedbank significantly decreases in the longer term with increasing time since burning up to 22 years. The community composition of the soil seedbank was strongly affected by geographical location, with sites closer to each other having similar composition. Only sites 1-year-since burn showed changes in the community composition due to burning.
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Brainard, Daniel C., Robin R. Bellinder, Russell R. Hahn, and Denis A. Shah. "Crop Rotation, Cover Crop, and Weed Management Effects on Weed Seedbanks and Yields in Snap Bean, Sweet Corn, and Cabbage." Weed Science 56, no. 3 (June 2008): 434–41. http://dx.doi.org/10.1614/ws-07-107.1.

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Three major hypotheses were examined in this study: (1) the density of summer annual weeds is reduced in crop rotation systems that include winter wheat compared to those with strictly summer annual crops, (2) the integration of a red clover in cropping systems reduces weed seedbank densities, and (3) changes in weed seedbanks due to crop rotation system have greater impact on future crops that are managed with cultivation alone, compared to those managed with herbicides. To test these hypotheses, five 3-yr rotation sequences were examined in central New York state: continuous field corn (FC); field corn with red clover (FC + CL); field corn–oats–wheat (FC/O/W); sweet corn–peas–wheat (SC/P/W), and SC/P/W with red clover (SC/P/W + CL). In the fourth year, sweet corn, snap beans, and cabbage were planted in subplots with three levels of weed management as sub-subplots: cultivation alone, reduced-rate herbicides (1/2×), and full-rate herbicides (1×). The trial was carried out in two separate cycles, from 1997 to 2000 (cycle 1) and from 1998 to 2001 (cycle 2). Crop rotations with strictly summer annual crops (FC) did not result in consistently higher weed seedbank densities of summer annual weeds compared to rotations involving winter wheat (FC/O/W; SC/P/W; SC/P/W + CL). Integration of red clover in continuous field corn resulted in higher weed seedbanks (cycle 1) or emergence (cycle 2) of several summer annual weeds compared to field corn alone. In contrast, integration of red clover in the SC/P/W rotation led to a 96% reduction in seedbank density of winter annuals in cycle 1, although this effect was not detected in cycle 2. Observed changes in weed seedbank density and emergence due to crop rotation resulted in increased weed biomass in the final year in only one case (sweet corn, cycle 2), and did not result in detectable differences in crop yields. In contrast, final year weed management had a strong effect on weed biomass and yield; cultivation alone resulted in yield losses for sweet corn (32 to 34%) and cabbage (0 to 7%), but not snap beans compared to either 1/2× or 1× herbicides.
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34

Jabbour, Randa, Eric R. Gallandt, Sarah Zwickle, Robyn S. Wilson, and Doug Doohan. "Organic Farmer Knowledge and Perceptions are Associated with On-Farm Weed Seedbank Densities in Northern New England." Weed Science 62, no. 2 (June 2014): 338–49. http://dx.doi.org/10.1614/ws-d-13-00098.1.

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Weed management remains a high priority for organic farmers, whose fields generally have higher weed density and species diversity than those of their conventional counterparts. We explored whether variability in farmer knowledge and perceptions of weeds and weed management practices were predictive of variability in on-farm weed seedbanks on 23 organic farms in northern New England. We interviewed farmers and transcribed and coded interviews to quantify their emphasis on concepts regarding knowledge of ecological weed management, the perceived risks and benefits of weeds, and the perceived risks and benefits of weed management practices. To characterize on-farm weed seedbanks, we collected soil samples from five fields at each farm (115 fields total) and measured germinable weed seed density. Mean weed seed density per farm ranged from 2,775 seeds m−2to 24,678 seeds m−2to a soil depth of 10 cm. Farmers most often reported hairy galinsoga and crabgrass species (Digitariaspp.) as their most problematic weeds. The proportion of the sum of these two most problematic weeds in each farm's seedbank ranged from 1 to 73% of total weed seed density. Farmer knowledge and perceptions were predictive of total seed density, species richness, and proportion of hairy galinsoga and crabgrass species. Low seed densities were associated with farmers who most often discussed risks of weeds, benefits of critical weed-free management practices, and learning from their own experience. These farmers also exhibited greater knowledge of managing the weed seedbank and greater understanding of the importance of a long-term strategy. Targeted education focusing on this set of knowledge and beliefs could potentially lead to improved application and success of ecological weed management in the future, thus decreasing labor costs and time necessary for farmers to manage weeds.
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35

Ball, Daniel A. "Weed Seedbank Response to Tillage, Herbicides, and Crop Rotation Sequence." Weed Science 40, no. 4 (December 1992): 654–59. http://dx.doi.org/10.1017/s0043174500058264.

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Changes in the weed seedbank due to crop production practices are an important determinant of subsequent weed problems. Research was conducted to evaluate effects of primary tillage (moldboard plowing and chisel plowing), secondary tillage (row cultivation), and herbicides on weed species changes in the soil seedbank in three irrigated row crop rotational sequences over a 3-yr period. The cropping sequences consisted of continuous corn for 3 yr, continuous pinto beans for 3 yr, or sugarbeets for 2 yr followed by corn in the third year. Cropping sequence was the most dominant factor influencing species composition in the seedbank. This was partly due to herbicide use in each cropping sequence producing a shift in the weed seedbank in favor of species less susceptible to applied herbicides. A comparison between moldboard and chisel plowing indicated that weed seed of predominant species were more prevalent near the soil surface after chisel plowing. The number of predominant annual weed seed over the 3-yr period increased more rapidly in the seedbank after chisel plowing compared to moldboard plowing unless effective weed control could be maintained to produce a decline in seedbank number. In this case, seedbank decline was generally more rapid after moldboard plowing. Row cultivation generally reduced seedbanks of most species compared to uncultivated plots in the pinto bean and sugarbeet sequences. A simple model was developed to validate the observation that rate of change in the weed seedbank is influenced by type of tillage and weed control effectiveness.
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36

CardiNa, John, Denise H. Sparrow, and Edward L. McCoy. "Spatial Relationships Between Seedbank and Seedling Populations of Common Lambsquarters (Chenopodium album) and Annual Grasses." Weed Science 44, no. 2 (June 1996): 298–308. http://dx.doi.org/10.1017/s0043174500093929.

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Predictions of weed seedling populations from seedbank data should characterize the spatial distribution as well as the composition and abundance of weeds. The spatial distribution of seedbank and seedling populations of common lambsquarters and annual grasses (giant foxtail, large crabgrass, and fall panicum) were described in moldboard plow and no-tillage soybean fields from 1990 to 1993. Spearman rank correlations between seedbank and seedling densities were significant for common lambsquarters in both tillages and all years, but for annual grasses correlations were significant only in no-tillage. Semivariograms showed spatial autocorrelation in seedbank and seedling populations of common lambsquarters in all years in no-till, but less often in the moldboard plow field. Annual grass seed and seedling populations were autocorrelated in the no-till field every year except 1993, and in the moldboard plow field in 1992 and 1993 only. Cross-semivariograms showed spatial continuity between seedbank and seedling population densities in 3 of 4 yr in no-till for common lambsquarters, and in all years of no-till and 1 yr of moldboard plow for annual grasses. Grey-scale field maps of common lambsquarters seedbanks corresponded visually to maps of seedling populations and could have been used to target control efforts, but visual correspondence between annual grass seedbank and seedling maps was poor. Seedbank and seedling mapping may be useful for site-specific management, but additional information is needed to understand the variation in the relationships between these two populations over time and space.
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37

Comino, E., B. P. Miller, and N. J. Enright. "Soil seedbanks in natural and restored boxironbark forests at Stawell Gold Mine, Victoria." Pacific Conservation Biology 10, no. 1 (2004): 9. http://dx.doi.org/10.1071/pc040009.

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Natural communities have the capacity to regenerate themselves, and this functional ecosystem attribute must be regarded as a key indicator of success for revegetation programmes. The accumulation of species (and individuals) as dormant propagules in a soil seedbank, representing potential future states for the vegetation, is one possible index of revegetation success. Here, we investigate the soil seedbanks for five natural vegetation (Box-Ironbark forest) remnants, a topsoil stockpile and three revegetated mine-site areas associated with gold mining at Stawell (Victoria, Australia). The revegetation efforts largely date from 1987 and, in terms of their composition and structure, are relatively similar to natural vegetation remnants. Soil samples were treated with heat or smoke (plus control) and were monitored for seedling emergence, species composition and density in the glasshouse for 150 days. Seedling densities in treated seedbank samples were high (2 200 to 17 500 seedlings m-2) while species richness was low, ranging from 10 to 20 species per sample. Exotic species made up 22?61 % of emergents and 33?50% of species observed. Correlation of seedbank composition and density with chemical attributes of soils, and with above ground (extant) vegetation at sites showed few significant relationships. Total species richness and the proportion of exotic species varied significantly between natural bushland remnants and revegetation areas. Richness was highest, and the proportion of exotic species was lowest in natural bushland samples. Total emergent numbers and the density of exotic emergents did not vary significantly between remnant bushland and revegetation areas. Declining vigour of some woody species in revegetation sites that are well represented in the seedbank, including Acacia pycnantha and A. genistifolia, indicates that the reintroduction of fire might be an appropriate management practice to facilitate long-term recovery of a functional community on these revegetated surfaces, but the potential for the establishment of weed species from the seed-bank following fire may pose a challenge to management.
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38

Graham, R. A., S. K. Florentine, J. E. D. Fox, and T. M. Luong. "The germinable soil seedbank of Eucalyptus victrix grassy woodlands at Roy Hill station, Pilbara district, Western Australia." Rangeland Journal 26, no. 1 (2004): 17. http://dx.doi.org/10.1071/rj04002.

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The paper reports soil seedbank species composition, of Eucalyptus victrix grassy woodlands, of the upper Fortescue River in the Pilbara District, Western Australia. In this study, our objectives were to investigate germinable soil seedbanks and species composition in response to three simulated seasons, using emergence. Variation in seed density from three depths was tested. Four field sites were sampled. Thirty samples were collected in late spring, after seed rain and before summer rainfall. From each sample spot, three soil depths (surface, 1–5, and 6–10 cm) were segregated from beneath surface areas of 100 cm2. Samples were later incubated in a glasshouse to simulate three different seasonal conditions (autumn, winter and spring). Germinating seedlings were recorded on emergence and grown until identified. Forty-one species germinated, comprising 11 grasses (7 annuals and 4 perennials), 25 annual herbs and 5 perennial herbs. Distribution patterns of germinable seed in both the important annual grass Eragrostis japonica and the perennial Eragrostis setifolia (a preferred cattle fodder species), suggest that seedbank accumulation differs among species and between sites. In part, this may be associated with the absence of grazing. Species with most total germinable seed were E. japonica (Poaceae; 603/m2), and the annual herbs Calotis multicaulis (Asteraceae; 346/m2), and Mimulus gracilis (Scrophulariaceae; 168/m2). Perennial grass seed was sparse. Spring simulation gave most germination (1059), followed by autumn (892) and winter (376) sets. Greatest species diversity was produced from the spring simulation (33 species), followed by autumn (26), and winter (22). Of the total germination, 92% came from 17 species that were represented in all three simulations. Of the 1227 grass seedlings counted, most were recruited from the surface soil (735), followed by the 5 (310) and 10 (182) cm depths. Marginally more grass seedlings germinated from the spring simulation (558) than the autumn set (523). Only 11.9% of grass germinants came from the winter simulation. All grass species recruited from the soil seedbanks had a C4 photosynthetic pathway. Except for Cenchrus ciliaris all grass species are native to Australia. Of the four sites sampled, one fenced to exclude cattle five years earlier had significantly more germination than the three unfenced sites. Seedbank sampling produced several new records for plants in the areas sampled.
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Steenwerth, K., K. Baumgartner, K. Belina, and L. Veilleux. "Vineyard Weed Seedbank Composition Responds to Glyphosate and Cultivation after Three Years." Weed Science 58, no. 3 (September 2010): 310–16. http://dx.doi.org/10.1614/ws-d-09-00043.1.

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This research compared effects of the weed control practice, soil cultivation, and the conventional practice, glyphosate application on weed seedbank, in a vineyard system. The experiment was conducted in a commercial wine-grape vineyard in the Napa Valley of northern California from 2003 to 2005. The annual treatments were “winter–spring glyphosate,” “spring cultivation,” “fall–spring cultivation,” and “fall cultivation–spring glyphosate,” and were applied “in-row,” under the vine. Composition of the weed seedbank collected in 2002 before treatment establishment did not differ among treatments. After 3 yr of weed treatments, detrended correspondence analysis indicated that the composition of spring cultivation and winter–spring glyphosate tended to differ from each other, but the remaining two treatments showed little differentiation. As determined by linear discriminant analysis, the specific weed species were associated with seedbanks of certain treatments. These were Carolina geranium, annual bluegrass, brome grasses, California burclover, and scarlet pimpernel, which do not pose problems with regard to physical aspects of grape production. Although ‘Zorro’ rattail fescue was ubiquitous among treatments, its distribution between depths in the cultivated treatments indicated that tillage provided some homogenization of seedbank along the vertical soil profile. The seedlings from the seedbank study were not congruent with those measured aboveground in the field, suggesting that both treatment and microclimatic effects in the field may have influenced germination, and thus, aboveground composition.
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40

Bean, Judith M., Gavin J. Melville, Ronald B. Hacker, Sharon Anderson, Alicia Whittington, and Stephen P. Clipperton. "Effects of fenced seed production areas and restoration treatments on the size and composition of the native grass seedbanks in moderately degraded rangelands in semiarid Australia." Rangeland Journal 38, no. 1 (2016): 47. http://dx.doi.org/10.1071/rj15065.

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Seed production areas containing populations of native grasses were fenced on topographically high areas at two study sites in the semiarid rangelands of north-west New South Wales, Australia. The surrounding slopes were initially almost bare of pastorally preferred grasses. Three restoration treatments (control, mechanical pitting, and contour-aligned branch piles) were established on these surrounding slopes and the size and composition of the native grass seedbanks determined. A positive influence of the seed production areas mostly occurred within 15 m of the fence and was probably insignificant beyond 33 m at both sites. On a hard-setting red earth site, the size of the native grass seedbank in all three treatments increased over 2 years with the greatest increase under the piles of branches and smaller increases in the pitting and control treatments. The piles of branches preferentially incorporated seed of the pastorally preferred species Monachather paradoxus Steud into the seedbank whereas pits preferentially incorporated seed of the pastorally unpreferred species Aristida jerichoensis (Domin) Henrad. Evidence generally pointed to incoming seed rain rather than the seedbank as the main source of new seedlings. On a medium-textured lithosol site neither the pits nor the branches treatment was effective in enhancing either the size or composition of the seedbank; in fact the piles of branches resulted in a decrease in its size.
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41

Forcella, Frank, Robert G. Wilson, Jack Dekker, Robert J. Kremer, John Cardina, Randy L. Anderson, David Alm, et al. "Weed seed bank emergence across the Corn Belt." Weed Science 45, no. 1 (February 1997): 67–76. http://dx.doi.org/10.1017/s0043174500092493.

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Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartweed, 25.1 (65); common purslane, 15.4 (135); common ragweed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigweed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotweed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June.
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42

Romaneckas, Kęstutis, Rasa Kimbirauskienė, Aušra Sinkevičienė, Iwona Jaskulska, Sidona Buragienė, Aida Adamavičienė, and Egidijus Šarauskis. "Weed Diversity, Abundance, and Seedbank in Differently Tilled Faba Bean (Vicia faba L.) Cultivations." Agronomy 11, no. 3 (March 11, 2021): 529. http://dx.doi.org/10.3390/agronomy11030529.

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Differently tilled faba bean cultivations, in particular, require a comprehensive study of weed diversity, abundance, and seedbank due to the lack of experimental data. Therefore, in 2016–2018, field trials were conducted at Vytautas Magnus University on the basis of a long-term tillage experiment. Conventional deep and shallow plowing, deep chiseling, shallow disking, and no-tillage systems were investigated. According to the results of the investigations, the air temperature and amount of precipitation during the vegetative season had a greater influence on the total number of weeds (r = 0.538 and 0.833 p > 0.05) than the types of tillage systems investigated. However, on average, a reduction in tillage intensity did not change the weed number, especially in disked and not tilled plots. On average, the biomass of weeds varied little between the treatments (from 105.9 to 125.7 g m−2) and mainly depended on the volume of forecrop residues (rannual = −0.982 p ≤ 0.01 and rperennial = 0.890 p ≤ 0.05). Higher total weed seedbanks were found in the disked (+43.0%) and not tilled (+21.6%) soils compared to deeply plowed ones. The weed seedbank was almost similarly distributed between the treatments, irrespective of the tillage depth and method used.
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43

Fortune, JA, PS Cocks, CK Macfarlane, and FP Smith. "Distribution and abundance of annual legume seeds in the wheatbelt of Western Australia." Australian Journal of Experimental Agriculture 35, no. 2 (1995): 189. http://dx.doi.org/10.1071/ea9950189.

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The size and composition of pasture legume seedbanks were estimated from 2 surveys on a 460-km west-east transect of the wheatbelt of Western Australia. Survey 1 (in spring) sampled naturalised legumes, and survey 2 (in summer) measured the amount and botanical composition of legume seed from selected sites. Seedbanks were examined in greater detail on 2 farms in the higher rainfall part of the wheatbelt. Survey 2 revealed that mean seedbank size of the poorest 40% of sites (those with 5200 kg seed/ha) was 61 kg/ha, and that 72% of seeds were naturalised clovers. In contrast, the best 60% of sites (those with >200 kg seed/ha) averaged 533 kg seed/ha, of which only 35% was naturalised clover seed, the remainder in both surveys being mainly subterranean clover (Trifolium subterraneum). Mean seed bank size (kg/ha) varied from 359 (survey 2) to 587 (survey 1) and, in both surveys, was poorly correlated with long-term mean annual rainfall and a number of soil parameters. On the 2 farms, seedbank size ranged from 300 to 345 kg/ha (in spring) and from 650 to 740 kg/ha (in summer). Trifolium glomeratum (cluster clover) and subterranean clover were the most widespread species in both surveys. They were present at 35 and 30 of the 57 survey sites, respectively, and at both farms. Most of the subterranean clover collected was cv. Geraldton (22 of 30 sites), the next most frequent cultivar was Dwalganup (6 sites). The currently recommended cultivar, Dalkeith, was found at only 5 sites. Several other legumes including T. tomentosum (16 sites), T. suffocatum (8 sites), Medicago truncatula (7 sites), T. hirtum (4 sites), and M. minima (4 sites) were common, while M. littoralis, M. polymorpha, T. dubium, T. cernuum, T. cherleri, and T. carnpestre were found at single sites. With few exceptions, these are naturalised species and were characterised by flowering times about 20 days later than sown legume cultivars, and seed sizes < 1 mg. The value of these widespread annual legumes to agricultural productivity and sustainability needs to be quantified and their adaptation to wheatbelt farming systems assessed.
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44

Rahman, A., T. K. James, J. E. Waller, and N. Grbavac. "Soil sampling studies for estimation of weed seedbanks." Proceedings of the New Zealand Plant Protection Conference 50 (August 1, 1997): 447–52. http://dx.doi.org/10.30843/nzpp.1997.50.11301.

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45

Vernooy, Ronnie, Bhuwon Sthapit, Gea Galluzzi, and Pitambar Shrestha. "The Multiple Functions and Services of Community Seedbanks." Resources 3, no. 4 (November 25, 2014): 636–56. http://dx.doi.org/10.3390/resources3040636.

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46

Wiles, Lori J., Douglass H. Barlin, Edward E. Schweizer, Harold R. Duke, and Douglas E. Whitt. "A New Soil Sampler and Elutriator for Collecting and Extracting Weed Seeds from Soil." Weed Technology 10, no. 1 (March 1996): 35–41. http://dx.doi.org/10.1017/s0890037x0004567x.

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A soil sampler, elutriator, and associated sample flushing device were designed and constructed for an intensive study of weed seedbanks. This equipment was used in 1993 to collect and process 4980 soil samples. The sampler was durable, core size was consistent, and sampling was efficient. Cores were approximately 200 cm3and two people could take 120 cores/h. The elutriator separated weed seeds from 36 of these cores at a time. Washing required 60 to 75 min depending on soil texture. Seeds as small as 0.3 mm in diam were recovered and almost 100% of the seeds were recovered from samples spiked with barnyardgrass, redroot pigweed, velvetleaf, and witchgrass. The flushing device was used to transfer sample contents from strainers of the elutriator to propyltex bags for drying and storing. Equipment like this, plus improved technology for identifying and counting seeds, is needed to make weed seedbank studies more feasible.
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47

Florentine, Singarayer, Sandra Weller, Alannah King, Arunthathy Florentine, Kim Dowling, Martin Westbrooke, and Bhagirath S. Chauhan. "Seed germination response of a noxious agricultural weed Echium plantagineum to temperature, light, pH, drought stress, salinity, heat and smoke." Crop and Pasture Science 69, no. 3 (2018): 326. http://dx.doi.org/10.1071/cp17308.

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Echium plantagineum is a significant pasture weed in the Mediterranean climatic zone of several countries, including Australia. This invasive weed, introduced as an ornamental into Australia (where it is known as Paterson’s curse), quickly became established and is now a significant weed of agriculture. Although E. plantagineum is a well-established, highly competitive weed that thrives under disturbance and is tolerant of a wide variety of conditions, including varying soil moisture and drought, and some aspects of its ecology remain unknown. This study investigated germination response to temperature and light, pH, soil moisture, salinity, and pre-germination exposure of seed to heat and smoke. Temperature was found to be more influential on germination than light and the species is tolerant to a wide range of pH. However, available moisture may limit germination, as may elevated salinity. Management of this weed requires approaches that minimise soil seedbank input or prevent germination of soil seedbanks.
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48

Norsworthy, Jason K., and Marcos J. Oliveira. "A Model for Predicting Common Cocklebur (Xanthium strumarium) Emergence in Soybean." Weed Science 55, no. 4 (August 2007): 341–45. http://dx.doi.org/10.1614/ws-06-185.

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The objective of this research was to develop a model to predict common cocklebur seedling emergence in spring tillage and no-spring-tillage systems in the presence and absence of a soybean canopy. A Weibull function was used to accumulate heat units (i.e., growing degree days) at a 2.5 cm soil depth on days when mean soil temperature, soil water potential, and soil thermal fluctuation were above established thresholds. The base temperature, soil water potential, and soil thermal fluctuation thresholds used for model development were 17 C, −100 kPa, and 7.5 C, respectively. A single function adequately described common cocklebur seedling emergence in the presence and absence of drill-seeded soybean from data combined over an artificial (2004) and natural seedbank (2005) (R2= 0.986). Model parameterization differed between the artificial and natural seedbank in the absence of spring tillage, but emergence was adequately described, regardless of soybean presence. Separate parameter estimates for the artificial and natural seedbanks were needed to adequately describe emergence in the system without spring tillage (R2= 0.975 to 0.984). The ability of the model to account for reduced emergence when soil moisture is limited or when daily thermal fluctuation requirements are not met could assist practitioners with assessments associated with field scouting for weeds as well as other management decisions.
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49

Cardina, John, Catherine P. Herms, and Douglas J. Doohan. "Crop rotation and tillage system effects on weed seedbanks." Weed Science 50, no. 4 (July 2002): 448–60. http://dx.doi.org/10.1614/0043-1745(2002)050[0448:cratse]2.0.co;2.

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50

Chen, Guoqi, Qinghu Liu, Yuhua Zhang, Jun Li, and Liyao Dong. "Comparison of Weed Seedbanks in Different Rice Planting Systems." Agronomy Journal 109, no. 2 (March 2017): 620–28. http://dx.doi.org/10.2134/agronj2016.06.0348.

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