scholarly journals Does seed mass drive interspecies variation in the effect of management practices on weed demography?

2020 ◽  
Author(s):  
Kazakou Elena ◽  
Fried Guillaume ◽  
Cheptou Pierre-Olivier ◽  
Gimenez Olivier
Keyword(s):  
Seed Bank ◽  
Management Practices ◽  
Seed Mass ◽  
Demographic Parameters ◽  
Weed Species ◽  
Plant Populations ◽  
Interspecies Variation ◽  
Weed Population Dynamics ◽  
Do So

AbstractOptimizing the effect of management practices on weed population dynamics is challenging due to the difficulties in inferring demographic parameters in seed banks and their response to disturbance. Here, we used a long-term plant survey between 2006 and 2012 in 46 French vineyards and quantified the effects of management practices (tillage, mowing and herbicide) on colonization, germination and seed survival of 30 weed species in relation to their seed mass. To do so, we used a recent statistical approach to reliably estimate demographic parameters for plant populations with a seed bank using time series of presence–absence data, which we extended to account for interspecies variation in the effects of management practices on demographic parameters. Our main finding was that when the level of disturbance increased (i.e., in plots with a higher number of herbicide, tillage or mowing treatments), colonization and survival in large-seeded species increased faster than in small-seeded species. High disturbance through tillage increased survival in the seed bank of species with high seed mass. The application of herbicides, considered as an intermediate disturbance, increased germination, survival and colonization probabilities of species with high seed mass. Mowing, representing habitats more competitive for light, increased the survival of species with high seed mass. Overall, the strong relationships between the effects of management practices and seed mass provides an indicator for predicting the dynamics of weed communities under disturbance.

scholarly journals Relation between Soil Weed Seedbank and Weed Management Practises and Diversity in Farms in Kisii Central Sub County, Nyanza

2020 ◽  
Vol 10 ◽  
pp. 1-14
Author(s):  
Charles N. Nyamwamu ◽  
Rebecca Karanja ◽  
Peter Mwangi
Keyword(s):  
Seed Bank ◽  
Weed Management ◽  
Management Practices ◽  
Soil Seed Bank ◽  
Shannon Index ◽  
Weed Seed ◽  
Weed Species ◽  
Western Kenya ◽  
Weed Diversity ◽  
Hand Weeding

This study sought to determine the relation between soil weed seed bank and weed management practices and diversity in farms in Kisii Central Sub County, Western Kenya. Eight administrative sub-locations were randomly selected. Ten farms were selected at equal distance along transect laid across each sub-location. Weed soil seed bank was assessed from soil samples collected from each of the farms; a sub-sample was taken from a composite sample of ten soil cores of 5cm diameter and 15cm deep and placed in germination trays in a greenhouse. Weed diversity in soil weed seedbank was calculated using the Shannon index (H’). Twelve weed species from 12 genera of nine families were recorded. Diversity of the weed species in soil weed seed bank was (H'=1.48). Weed management practises significantly affected weed species soil weed seedbank reserves. Use of inefficient and ineffective hand-weeding techniques resulted in high weed species diversity and abundance.

scholarly journals Does seed mass drive interspecies variation in the effect of management practices on weed demography?

2021 ◽  
Author(s):  
Elena Kazakou ◽  
Guillaume Fried ◽  
Pierre‐Olivier Cheptou ◽  
Olivier Gimenez
Keyword(s):  
Management Practices ◽  
Seed Mass ◽  
Interspecies Variation

Effects of Initial Seed-Bank Density on Weed Seedling Emergence during the Transition to an Organic Feed-Grain Crop Rotation

Weed Science ◽  
2009 ◽  
Vol 57 (5) ◽  
pp. 533-540 ◽  
Author(s):  
Richard G. Smith ◽  
Randa Jabbour ◽  
Andrew G. Hulting ◽  
Mary E. Barbercheck ◽  
David A. Mortensen
Keyword(s):  
Seed Bank ◽  
Weed Management ◽  
Cover Crop ◽  
Management Practices ◽  
Transition Period ◽  
Red Clover ◽  
Weed Seed ◽  
Weed Species ◽  
Organic Certification ◽  
Weed Seeds

The transition period to certified organic production can present a significant weed management challenge for growers. Organic certification requires that prohibited fertilizers and pesticides must not have been used for 36 mo before harvest of the first organic crop. Understanding how organic management practices and initial weed seed-bank densities affect weed population dynamics during the transition period may improve weed management efficacy and adoption of organic practices. We examined how tillage systems (full or reduced) and cover crop species planted during the first transition year (rye or a mixture of timothy and red clover) affect the seedling densities of three common annual weed species, common lambsquarters, velvetleaf, and foxtail spp., during the 3-yr transition period. Weed seeds were applied in a one-time pulse at the beginning of the study at three densities, low, medium, and high (60, 460, and 2,100 seeds m−2, respectively), and cumulative seedling densities of each species were assessed annually. Treatment factors had variable and species-specific effects on weed seedling densities. In general, the full-tillage system, with an initial cover crop of timothy and red clover, resulted in the lowest density of weed seedlings following seed-bank augmentation. There was little consistent association between the initial densities of applied weed seeds in the weed seed bank at the start of the transition and weed seedling densities at the end of the transition period. This suggests that when multiple crop and weed cultural management practices are employed during the organic transition period, initial failures in weed management may not necessarily lead to persistent and intractable annual weed species management problems following organic certification.

No-tillage altered weed species dynamics in a long-term (36-year) grain sorghum experiment in southeast Texas

Weed Science ◽  
2020 ◽  
Vol 68 (5) ◽  
pp. 476-484
Author(s):  
Prabhu Govindasamy ◽  
Debalin Sarangi ◽  
Tony Provin ◽  
Frank Hons ◽  
Muthukumar Bagavathiannan
Keyword(s):  
Management Practices ◽  
Grain Sorghum ◽  
Base Temperature ◽  
Weed Species ◽  
Perennial Weed ◽  
Species Dominance ◽  
Species Dynamics ◽  
Ct System ◽  
The Impact

AbstractTillage regimes can influence weed population dynamics and, consequently, the choice of appropriate weed management practices. Studies were conducted in 2016 and 2017 in a long-term (36-yr) grain sorghum [Sorghum bicolor (L.) Moench ssp. bicolor] experiment at Texas A&M University, College Station, to determine the impact of long-term no-till (NT) and conventional till (CT) systems on weed species dynamics. Higher densities of johnsongrass [Sorghum halepense (L.) Pers.], prostrate spurge [Chamaesyce humistrata (Engelm. ex A. Gray) Small], waterhemp [Amaranthus tuberculatus (Moq.) Sauer], and henbit (Lamium amplexicaule L.) were recorded in the NT system compared with the CT system. Further, the NT system showed greater weed diversity (Shannon-Wiener index, H = 0.8) and species richness (S = 6.2), compared with the CT system (H = 0.6, S = 4.2). Seedling emergence of some dominant weed species was also delayed in the NT system. In the CT system, 50% emergence of S. halepense (8.5 C base temperature) and waterhemp (10 C base temperature) occurred at 59 and 63 growing degree days (GDD), respectively, whereas 68 and 75 GDD, respectively, were required in the NT system. Further, a greater proportion (61%) of the viable seedbank was present at the top 5 cm of the soil in the NT system compared with the CT system (46%). Overall, findings from this 36-yr-long tillage experiment have revealed that the NT system had greater weed densities (especially of the perennial weed S. halepense) and a high proportion of weed seeds (particularly small-seeded annuals) on the topsoil layer, corroborating some earlier reports that were based on short-term investigations. Findings indicate that growers transitioning to NT systems should be mindful of potential shifts in weed species dominance and develop appropriate management tactics.

scholarly journals Comparison of the seed bank with the aboveground vegetation of field weeds in the neighbourhood of Mikulov in South Moravia

2011 ◽  
Vol 59 (1) ◽  
pp. 277-290
Author(s):  
Magda Zdražílková
Keyword(s):  
Endangered Species ◽  
Seed Bank ◽  
Cultural Practice ◽  
Weed Species ◽  
Rare And Endangered Species ◽  
Close Relationship ◽  
Rare And Endangered ◽  
Phytosociological Relevés ◽  
South Moravia

The processed set of phytosociological relevés indicated that at the present time the field weed associations are composed particularly of species of wide ecological amplitude. The rare and endangered species appeared only on localities usually not much affected by chemicals. Most of the endangered species of field weeds were found to survive primarily on small private farms, in the headland of fields or on field edges near the natural reserves.The results indicated that the type of crop had a significant effect on the composition of the current aboveground vegetation. There is a close relationship between the type of crop and the applied cultural practice. Its effect is much more important than the effect of the overall method of management. However, long-term application of herbicides may eliminate some weed species from the seed bank and as a consequence also from the current vegetation. That is the reason why crop rotation is so important for preserving the species diversity of weeds in tandem with limited applications of herbicides.

scholarly journals Weed community structure and soybean yields in a long-term organic cropping systems experiment

Weed Science ◽  
2019 ◽  
Vol 67 (6) ◽  
pp. 673-681 ◽  
Author(s):  
Margaret G. Ball ◽  
Brian A. Caldwell ◽  
Antonio DiTommaso ◽  
Laurie E. Drinkwater ◽  
Charles L. Mohler ◽  
...  
Keyword(s):  
Community Structure ◽  
Weed Management ◽  
Management Practices ◽  
Cropping Systems ◽  
Nutrient Inputs ◽  
Weed Species ◽  
Soybean Yield ◽  
Weed Density ◽  
Weed Species Richness

AbstractWeed management is a major challenge in organic crop production, and organic farms generally harbor larger weed populations and more diverse communities compared with conventional farms. However, little research has been conducted on the effects of different organic management practices on weed communities and crop yields. In 2014 and 2015, we measured weed community structure and soybean [Glycine max (L.) Merr.] yield in a long-term experiment that compared four organic cropping systems that differed in nutrient inputs, tillage, and weed management intensity: (1) high fertility (HF), (2) low fertility (LF), (3) enhanced weed management (EWM), and (4) reduced tillage (RT). In addition, we created weed-free subplots within each system to assess the impact of weeds on soybean yield. Weed density was greater in the LF and RT systems compared with the EWM system, but weed biomass did not differ among systems. Weed species richness was greater in the RT system compared with the EWM system, and weed community composition differed between RT and other systems. Our results show that differences in weed community structure were primarily related to differences in tillage intensity, rather than nutrient inputs. Soybean yield was lower in the EWM system compared with the HF and RT systems. When averaged across all four cropping systems and both years, soybean yield in weed-free subplots was 10% greater than soybean yield in the ambient weed subplots that received standard management practices for the systems in which they were located. Although weed competition limited soybean yield across all systems, the EWM system, which had the lowest weed density, also had the lowest soybean yield. Future research should aim to overcome such trade-offs between weed control and yield potential, while conserving weed species richness and the ecosystem services associated with increased weed diversity.

scholarly journals Soil seed bank of plant species as a function of long-term soil management and sampled depth

2011 ◽  
Vol 29 (4) ◽  
pp. 725-736 ◽  
Author(s):  
G Concenço ◽  
J.C Salton ◽  
R.C Brevilieri ◽  
P.B Mendes ◽  
M.L Secretti
Keyword(s):  
Seed Bank ◽  
Soil Seed Bank ◽  
Soil Management ◽  
Field Capacity ◽  
Dry Mass ◽  
Conventional Tillage ◽  
Management Systems ◽  
Weed Species ◽  
Tillage System

This study aimed at assessing the level of weed infestation indifferent areas that were submitted to different soil management for 16 years. Four management systems were studied: (1) agriculture only under conventional tillage system; (2) agriculture only under no-till system; (3) crop-livestock integrationcrop-livestock integration; (4) livestock only. These areas were sampled at three soil depths (0-5, 5-10 and 10-15 cm), and soil was stored in plastic pots and taken to a greenhouse, where soil moisture and weight were standardized. Soil was kept near 70% moisture field capacity, being revolved every 20 days when all seedling emerged from soil were counted, identified and collected for dry mass assessment. The soil coverage by weeds, number of weed seedlings and dry mass of the weedy community were assessed. A phytoecological analysis was conducted. Weed composition is differentdifferent among management systems after 16 years. Areas with livestock showed much smaller number of weed species in comparison to systems where only grain crops are grown. The presence of livestock affects the potential of germination of soil seed bank. Agriculture systems are similar in terms of weed composition along soil profile, while systems involving livestock show little relation in what regards such sampled depths. Conservationist models of land exploration contribute to reduce severity of weed species occurrence in the long term.

Weed Community Response to Saffron–Black Zira Intercropping

Weed Science ◽  
2008 ◽  
Vol 56 (3) ◽  
pp. 400-407 ◽  
Author(s):  
Mohsen B. Mesgaran ◽  
Hamid R. Mashhadi ◽  
Mahmood Khosravi ◽  
Eskandar Zand ◽  
Hasan Mohammad-Alizadeh
Keyword(s):  
Seed Bank ◽  
Weed Management ◽  
Management Practices ◽  
Soil Depth ◽  
Community Response ◽  
Specific Pattern ◽  
Planting Density ◽  
Weed Species ◽  
Common Lambsquarters ◽  
Viable Seeds

Intercropping is an eco-friendly approach for reducing weed problems through nonchemical methods. Intercrop effects on weed community structure have rarely been studied. A 6-yr study was initiated in 1999 and the response of aboveground weed flora (1999–2002 and 2005) and seed bank (2005) to the intercropping of saffron and black zira, two perennial crops was investigated. Mixtures consisted of 0/100, 25/75, 50/50, 75/25, and 100/0 saffron/black zira ratios, each planted at three densities: 30, 50, and 70 plant m−2. The effect of planting density on weed populations was variable and in most cases not significant. However, mixture ratios caused drastic species compositional changes in the weed community for which univariate and multivariate analyses explored four major associations: (1) weeds that favored a higher ratio of saffron in mixtures (e.g., grasses, field bindweed, pigweeds), (2) weeds that preferred a higher ratio of black zira in mixtures (e.g., Persian speedwell, Brassicaceae complex, Polygoaceae complex, and earthsmoke), (3) weeds that were more abundant in 50/50 mixtures (e.g., Caryophyllaceae complex), and (4) weeds that showed no specific pattern (e.g., common lambsquarterss). Pigweeds, prostrate knotweed, and common lambsquarters dominated the viable seed bank with relative densities of 48, 28, and 8%, respectively. The seed bank of most weed species responded to mixture ratios in a similar manner to those of their corresponding aboveground flora. Seed density decreased as soil depth increased, leading to the accumulation of 66, 22, and 12% of viable seeds in soil layers of 0–5, 5–15 and 15–25 cm, respectively. Greater weed and seed densities were found in more pure stands of black zira. These findings contribute to improving current understanding of crop–weed community structures and may help in developing weed management practices.

The major weedy biotypes of proso millet (Panicum miliaceum) in Canada

1986 ◽  
Vol 64 (6) ◽  
pp. 1188-1198 ◽  
Author(s):  
Marguerite Bough ◽  
Joseph C. Colosi ◽  
Paul B. Cavers
Keyword(s):  
Seed Bank ◽  
Management Practices ◽  
Selection Process ◽  
Effective Control ◽  
Panicum Miliaceum ◽  
Proso Millet ◽  
Crop Types ◽  
Black Seeds ◽  
And Control

Proso millet, Panicum miliaceum L., has become a problem weed in corn-growing areas of Canada over the last 15 years. Several different biotypes of this weed exist, and one of the features by which they may be distinguished from one another is seed colour. Those plants with dark olive – bronze – black seeds that shatter readily are the most difficult to control. Part of their success as weeds is due to their ability to form a long-term viable seed bank in the soil, making quick elimination from an area impossible. Other biotypes closely resemble crop types and have little dormancy or ability to form a long-term seed bank. Between these two extremes are 'crown' and some 'golden' biotypes, some populations of which have weedy characteristics that may make them more aggressive weeds as the selection process continues. Some biotypes are more readily controlled than others by a combination of management practices, including rotation and spraying. Good chemical control is available for use in some broad-leaved crops (e.g., soybeans), but consistently effective control of this weed in corn has not yet been achieved. Thus, a knowledge of the ecology of the weed can assist in other forms of management. Each biotype that has been discovered in Canada is described and illustrated, together with an outline of ecological characteristics that may aid in its identification and control.

scholarly journals Soil weed seed bank: Importance and management for sustainable crop production- A Review

2016 ◽  
Vol 13 (2) ◽  
pp. 221-228 ◽  
Author(s):  
MM Hossain ◽  
M Begum
Keyword(s):  
Life Cycle ◽  
Seed Bank ◽  
Crop Production ◽  
Management Practices ◽  
Sole Source ◽  
Seed Banks ◽  
Weed Seed ◽  
Weed Species ◽  
Surrounding Environment ◽  
Weed Seeds

The seed bank is the resting place of weed seeds and is an important component of the life cycle of weeds. Seed banks are the sole source of future weed populations of the weed species both annuals and perennials that reproduce only by seeds. For this reason, understanding fate of seeds in the seed bank can be an important component of overall weed control. When weed seeds enter the seed bank, several factors influence the duration for which seeds persist. Seeds can sense the surrounding environment in the seed bank and use these stimuli to become dormant or initiate germination. Soil and crop management practices can directly influence the environment of seeds in the soil weed seed bank and can thus be used to manage seed longevity and germination behavior of weed seeds.J. Bangladesh Agril. Univ. 13(2): 221-228, December 2015

Sign in / Sign up

Export Citation Format

Share Document