Natural Far Red Irradiation and Weed Seed Persistence in the Soil

AbstractProso millet (Panicum miliaceumL.) is both a crop and a weed in many parts of the world. The weedy biotypes exhibit a wide range of seed colours, but the strains with the most persistent seeds are distinguished by darker seeds. This paper compares the seed biology of a range of biotypes from Canada and demonstrates that darker seeds have heavier seed coats, imbibe and germinate more slowly, and suffer less imbibition damage (measured as electrolyte leakage). It is concluded that all these attributes contribute to the increased persistence in the soil of the dark-seeded weedy biotypes. Imbibition damage is widely implicated in poor emergence and low vigour of crop seeds, but has not previously been considered in the context of weed seed persistence.

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Chemical and Physical Defense of Weed Seeds in Relation to Soil Seedbank Persistence

Weed Science ◽

10.1614/ws-07-196.1 ◽

2008 ◽

Vol 56 (5) ◽

pp. 676-684 ◽

Cited By ~ 47

Author(s):

Adam S. Davis ◽

Brian J. Schutte ◽

James Iannuzzi ◽

Karen A. Renner

Keyword(s):

Seed Coat ◽

Half Life ◽

Weed Seed ◽

Protected Species ◽

Short Term ◽

Common Lambsquarters ◽

Seed Persistence ◽

Physical Defense ◽

Soil Seedbank

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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Weed Seed Persistence and Microbial Abundance in Long-Term Organic and Conventional Cropping Systems

Weed Science ◽

10.1614/ws-d-10-00142.1 ◽

2011 ◽

Vol 59 (2) ◽

pp. 202-209 ◽

Cited By ~ 20

Author(s):

Silke D. Ullrich ◽

Jeffrey S. Buyer ◽

Michel A. Cavigelli ◽

Rita Seidel ◽

John R. Teasdale

Keyword(s):

Microbial Biomass ◽

Half Life ◽

Soil Microbial Biomass ◽

Farming Systems ◽

Conventional System ◽

Weed Seed ◽

Common Lambsquarters ◽

Seed Persistence ◽

Soil Microbial ◽

Smooth Pigweed

Weed seed persistence in soil can be influenced by many factors, including crop management. This research was conducted to determine whether organic management systems with higher organic amendments and soil microbial biomass could reduce weed seed persistence compared with conventional management systems. Seeds of smooth pigweed and common lambsquarters were buried in mesh bags in organic and conventional systems of two long-term experiments, the Farming Systems Project at the Beltsville Agricultural Research Center, Maryland, and the Farming Systems Trial at the Rodale Institute, Pennsylvania. Seed viability was determined after retrieval at half-year intervals for 2 yr. Total soil microbial biomass, as measured by phospholipid fatty acid (PLFA) content, was higher in organic systems than in conventional systems at both locations. Over all systems, locations, and experiments, viable seed half-life was relatively consistent with a mean of 1.3 and 1.1 yr and a standard deviation of 0.5 and 0.3 for smooth pigweed and common lambsquarters, respectively. Differences between systems were small and relatively inconsistent. Half-life of smooth pigweed seeds was shorter in the organic than in the conventional system in two of four location-experiments. Half-life of common lambsquarters was shorter in the organic than in the conventional system in one of four location-experiments, but longer in the organic than in the conventional system in two of four location-experiments. There were few correlations between PLFA biomarkers and seed half-lives in three of four location-experiments; however, there were negative correlations up to −0.64 for common lambsquarters and −0.55 for smooth pigweed in the second Rodale experiment. The lack of consistent system effects on seed persistence and the lack of consistent associations between soil microbial biomass and weed seed persistence suggest that soil microorganisms do not have a dominating role in seed mortality. More precise research targeted to identifying specific microbial functions causing seed mortality will be needed to provide a clearer picture of the role of soil microbes in weed seed persistence.

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Seedbank persistence of four summer grass weed species in the northeast cropping region of Australia

PLoS ONE ◽

10.1371/journal.pone.0262288 ◽

2022 ◽

Vol 17 (1) ◽

pp. e0262288

Author(s):

Bhagirath Singh Chauhan ◽

Sudheesh Manalil

Keyword(s):

Weed Management ◽

Soil Surface ◽

Integrated Weed Management ◽

Burial Depth ◽

Weed Seed ◽

Weed Species ◽

Seed Persistence ◽

No Till ◽

Buried Seeds ◽

Grass Weed

Summer grass weed species are a particular problem in the northeast cropping region of Australia because they are prolific seeders and favor no-till systems. Information on weed seed persistence levels can be used for the development of effective and sustainable integrated weed management programs. A field study was conducted over 42 months to evaluate the seedbank persistence of Chloris truncata, C. virgata, Dactyloctenium radulans, and Urochloa panicoides as affected by burial depth (0, 2, and 10 cm). Regardless of species, buried seeds persisted longer than surface seeds and there was no difference in seed persistence between 2 and 10 cm depths. Surface seeds of C. truncata depleted completely in 12 months and buried seeds in 24 months. Similarly, C. virgata seeds placed on the soil surface depleted in 12 months. Buried seeds of this species took 18 months to completely deplete, suggesting that C. truncata seeds persist longer than C. virgata seeds. Surface seeds of D. radulans took 36 months to completely deplete, whereas about 7% of buried seeds were still viable at 42 months. U. panicoides took 24 and 42 months to completely exhaust the surface and buried seeds, respectively. These results suggest that leaving seeds on the soil surface will result in a more rapid depletion of the seedbank. Information on seed persistence will help to manage these weeds using strategic tillage operations.

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Effect of hypoxia on buried weed seed germination

Weed Research ◽

10.1111/j.1365-3180.1995.tb01629.x ◽

1995 ◽

Vol 35 (5) ◽

pp. 343-351 ◽

Cited By ~ 78

Author(s):

S. BENVENUTI ◽

M. MACCHIA

Keyword(s):

Seed Germination ◽

Weed Seed

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Modelling the long‐term impact of harvest weed seed control for species like Bromus diandrus and Hordeum spp. that shed a portion of seed prior to harvest

Weed Research ◽

10.1111/wre.12489 ◽

2021 ◽

Author(s):

Catherine P. D. Borger ◽

Daniel Petersen ◽

Gurjeet S. Gill ◽

Brian Schutte

Keyword(s):

Weed Seed ◽

Bromus Diandrus ◽

Long Term Impact

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Analysis of Quality of Backyard Compost and Its Potential Utilization as a Circular Bio-Waste Source

Applied Sciences ◽

10.3390/app11104392 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4392

Author(s):

Apolka Ujj ◽

Kinga Percsi ◽

Andras Beres ◽

Laszlo Aleksza ◽

Fernanda Ramos Diaz ◽

...

Keyword(s):

Crop Production ◽

Basic Education ◽

Raw Materials ◽

Nutrient Content ◽

Quality Analysis ◽

Weed Seed ◽

Quality Properties ◽

Seed Dispersion ◽

Materials Used

The use and quality analysis of household compost have become very important issues in recent years due to the increasing interest in local food production and safe, self-produced food. The phenomenon was further exacerbated by the COVID-19 pandemic quarantine period, which gave new impetus to the growth of small home gardens. However, the knowledge associated with making high-quality compost is often lacking in home gardeners. Therefore, the objective of this research was to find answers to the following questions: can the quality of backyard compost be considered safe in terms of toxicity and nutrient content? Can weed seed dispersion affect the usability of backyard compost? In general, can the circulation of organic matter be increased with the spread of home composting? In this study, 16 different house composts were analysed for stability, weed seed contamination, toxic elements, and nutrient content using analysis of variance. The results of the research showed that the quality properties of the composts (including their weed seed dispersion effect) were greatly influenced by the different techniques and raw materials used. The toxicity levels, as well as the content of macro and microelements, were within the parameters of safe-quality compost. The specific macronutrient (Ca, Mg) and micronutrient (Fe, Mn) contents of the tested composts have a similar and, in some cases, more favorable nutrient supply capacity in crop production than the frequently-used cow manure-based composts. With a plan of basic education on composting, there is potential to encourage farmyard composting.

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Long‐term impact of legume‐based cropping with chemical and integrated fertilisation on viable weed seed density, diversity and community structure

Weed Research ◽

10.1111/wre.12494 ◽

2021 ◽

Author(s):

Chaitanya P. Nath ◽

Kali K. Hazra ◽

Chandra S. Praharaj ◽

Ummed Singh ◽

Sati S. Singh ◽

...

Keyword(s):

Community Structure ◽

Seed Density ◽

Weed Seed ◽

Long Term Impact

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Influence of chaff and chaff lines on weed seed survival and seedling emergence in Australian cropping systems

Weed Technology ◽

10.1017/wet.2020.142 ◽

2020 ◽

pp. 1-22

Author(s):

Michael J. Walsh ◽

Annie E. Rayner ◽

Annie Rutledge ◽

John C. Broster

Keyword(s):

Cropping Systems ◽

Seedling Emergence ◽

Field Studies ◽

Wild Oat ◽

Weed Seed ◽

Weed Species ◽

Environment Effect ◽

Seed Survival ◽

Cropping Seasons ◽

Rigid Ryegrass

Abstract Chaff lining and chaff tramlining are harvest weed seed control (HWSC) systems that involve the concentration of weed seed containing chaff material into narrow (20 to 30 cm) rows between or on the harvester wheel tracks during harvest. These lines of chaff are left intact in the fields through subsequent cropping seasons in the assumption that the chaff environment is unfavourable for weed seed survival. The chaff row environment effect on weed seed survival was examined in field studies, while chaff response studies determined the influence of increasing amounts of chaff on weed seedling emergence. The objectives of these studies were to determine 1) the influence of chaff lines on the summer-autumn seed survival of selected weed species; and 2) the influence of chaff type and amount on rigid ryegrass seedling emergence. There was frequently no difference (P>0.05) in survival of seed of four weed species (rigid ryegrass, wild oat, annual sowthistle and turnip weed) when these seed were placed beneath or beside chaff lines. There was one instance where wild oat seed survival was increased (P<0.05) when seed were placed beneath compared to beside a chaff line. The pot studies determined that increasing amounts of chaff consistently resulted in decreasing numbers of rigid ryegrass seedlings emerging through chaff material. The suppression of emergence broadly followed a linear relationship where there was approximately a 2.0% reduction in emergence with every 1.0 t ha-1 increase in chaff material. This relationship was consistent across wheat, barley, canola and lupin chaff types, indicating that the physical presence of the chaff was more important than chaff type. These studies indicated that chaff lines may not affect the over summer-autumn survival of the contained weed seeds but the subsequent emergence of weed seedlings will be restricted by high amounts of chaff (>40 t ha-1).

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