Crop Weed Research Articles

THE PRE-em USE OF SOME HERBICIDES IN THE CONTROL OF WEEDS IN POTATOES AND THEIR INFLUENCE ON THE YIELD

In order to mitigate the problem with weeds in the potato crop in the 2017 growing season in the towns Bogovinje-Tetovo (Polog region), a field experiment was established according to the randomized block system with three replications with experimental plot sizes of 21 m2. In the experiment, we investigated the structure of weeds, the degree of appearance, the efficacy of herbicides and the eventual phytotoxicity of the herbicides used. The potato planted was the cultivar "Silvana" and the following treatment variants were included: pendimetalin 5 l/ha, linuron 2.5 l/ha, metobromuron 3 l/ha, metobromuron 4 l/ha, metribuzin 0.75 kg/ha PRE-em, metribuzin 1 kg/h PRE-em, mechanical controls and absolute controls. From the obtained results, it was found that the structure of weeds consists of 9 types of weeds, of which 3 species from the group of monocotyledonous weeds and 6 species from the group of dicotyledonous weeds. The number of weeds was 126 plants/m2. The dominant weeds were Echinochloa crus-galli with 93.7 plants/m2, Polygonum lapathifolium with 10.0 plants/m2, and Polygonum aviculare with 9.3 plants/m2. The efficiency of herbicides in the fight against dicotyledonous weeds has been from 97.7-100%, monocotyledonous weeds from 95.8-98.2%, while the overall efficiency without geophytes has been from 96.8-98.4%. Regarding phytotoxicity in the potato culture, no signs of phytotoxicity were observed in any variant of the treatment.

Efficacy of herbicidal treatments in controlling weeds in sugar beet crop and their side effects on subsequent crops

Efficacy of herbicidal treatments in controlling weeds in sugar beet crop and their side effects on subsequent crops

Selectivity of Herbicides in Controlling Weeds in Corn (Zea mays L) With A Tegel and Jajar Legowo Planting Pattern in West Aceh Regency

Maize (Zea mays L.) has a strategic role in meeting global food needs. How is the selectivity of herbicides in cultivation patterns 1 (single rows) and 2 (double rows) in Maize plants (Zea Mays L), how is the combination of herbs and plant pattern suitable for the management of weeds in corn crops (Zea mays L), how are the interactions of selectivities of herbicides and cultivation of maize (Zea mays L). This study uses Random Group Design (RGD) factorial patterns where factor 1 (herbicide) and factor 2 (planting pattern). The herbicide is composed of 4 types: H0 (control), H1 (Atrazine 180g/l + Mesotrione 40g/ l + Nicosulfuron 20 g/l, H2 (Atazine 500g/L, Mesotrione 50 g/L) and H3 (Topramezone 10 g/ L + Atrazine 300 g/ l). While the planting pattern consists of 2 types: P1: single row (70 x 20 cm) and P2: double rows (100x20x40 cm). Some conclusions were obtained, among others: The use of the herbicide atrazine in several formulas within the tile and legowo planting patterns does not cause poisoning in corn plants. The combination of herbicides (Topramezon 10 g/l and Atrazine 300 g/l / Tile) is most suitable for corn plants. There is an interaction between the herbicide and the planting pattern on the parameters of ear weight without husk and ear length without husk, which shows significant differences

Evaluation of Pyroxasulfone Crop Safety and Weed Control for California Tree Nut Orchards

Pyroxasulfone is a very long chain fatty acid (VLCFA) inhibitor (group 15) with potential for preemergence weed control in orchard crops and would be beneficial for reducing selection pressure for resistance to more commonly used herbicides, such as glyphosate. Pyroxasulfone is registered and widely used in corn and soybeans in the United States as a solo product and in several premix formulations. However, there is limited published information on the performance and safety of pyroxasulfone in tree nut orchard systems. To assess the potential fit for pyroxasulfone in this crop sector, a series of crop safety and weed control efficacy experiments were carried out in key California orchard crops and in fallow fields with common orchard weeds. The non-crop studies were conducted near Davis, CA, to evaluate winter annual weed control with pyroxasulfone in comparison with pendimethalin and indaziflam. In addition, an irrigation incorporation experiment was conducted in summer to evaluate the effects of incorporation timing on pyroxasulfone, pendimethalin, and indaziflam efficacy as a measure of relative stability. Orchard weed control experiments were conducted in spring in an almond orchard near Arbuckle, CA, and a walnut orchard near Davis, CA. The orchard experiments included pyroxasulfone, pendimethalin, and indaziflam in various rate combinations with glufosinate. To evaluate crop safety, 2-year experiments were conducted to evaluate repeated applications of above-label rates of pyroxasulfone at 1199 g·ha−1 and S-metolachlor at 14,010 g·ha−1 on 1- to 2-year-old almond, pistachio, and walnut trees near Davis. Pyroxasulfone performed similarly to commercial standards with up to 95% control of broadleaf and grass weeds with pyroxasulfone and indaziflam providing 96% to 100% control of annual bluegrass, and pyroxasulfone (293 g·ha−1) being the only herbicide to suppress (>70%) common lambsquarters at 60 days after treatment (DAT). Other weeds controlled by pyroxasulfone include swinecress, redroot pigweed, yellow nutsedge, and Italian ryegrass. No differences were found among treatments in the incorporation timing study indicating adequate stability on the soil surface under summer conditions. Crop injury was not observed in the established orchards or the young orchard studies and there were no treatment effects on tree trunk diameter of almond, pistachio, and walnut in the 2-year crop safety experiments. These results indicate a potential for pyroxasulfone in California tree nut orchard systems that would be an additional site of action and beneficial for management of herbicide-resistant weeds in these crops.

Effect of crop establishment method and weed management practices on weed and rice yield under DSR system

Effect of crop establishment method and weed management practices on weed and rice yield under DSR system

Combining a field experiment and literature to model the regrowth probability of perennial storage organs fragmented by tillage: Case study of Cirsium arvense (L.) Scop

Management of perennial weeds has become increasingly difficult with the reduction of herbicide use. Creeping perennials accumulate reserves in specialized belowground organs from which they regenerate new plants after a disturbance. Through tool selection, tillage operations could be optimized to reduce perennial-weed reserves and limit regeneration. In the present study, the effect of five tools on the fragmentation of the creeping roots of Cirsium arvense (L.) Scop. (Canada thistle), a major perennial weed in arable crops, were analysed. A field trial was set up to measure the lengths of the root fragments left after tillage. Five tools were tested: mouldboard ploughing, rotary harrow, disc harrow, rigid-tine cultivator and goose-foot cultivator. Fragment-length distribution varied according to the tool: rotary harrow left the smallest (3.7 cm on average) and least variable fragment lengths, mouldboard ploughing the longest (12.7 cm) and most variable ones. The other tools produced intermediate-sized fragments (8–10 cm). Based on these results and literature, a model was proposed to predict perennial-weed regeneration probability from storage-organ fragments after one tillage run. The effects of six factors, which were agronomic (tillage tool), environmental (soil conditions and temperature) and biological (storage-organ fragment diameter, maximal belowground-shoot length and pre-tillage storage-organ distribution), were tested through a sensitivity analysis. According to the model, the probability of fragment regeneration success is lower for the rotary harrow than for the mouldboard plough. The most important drivers of fragment regeneration success were the biological traits: fragment diameter and maximal belowground-shoot length per unit fragment biomass. The present model should be complemented to predict the effect of tillage on perennial-weed regrowth and help improving non-chemical weed-management strategies. To achieve this, further research is needed on plant regrowth potential from storage organs and their architecture in the soil.

Unveiling the impact of winter cover crops and weedy fallow on the soil seedbank

Cover crops (CCs) are recognised as valuable for weed management, while fallow soil between cash crop seasons likely increases weed presence. Weeds may offer similar ecosystem services as CCs, although they pose a risk of seedbank buildup. This study evaluated the impact of two winter CC systems (3-year triticale cultivation, TRIT; and a 3-year succession of rye, clover, and mustard, RCM) compared to weedy fallow (WF) on weed seedbank size and composition in a 3-year ‘maize (Zea mays L.)–maize–soybean (Glycine max (L.) Merr)’ crop succession. After 3 years, seed density of spring/summer weeds reduced in all treatments, potentially stemming from herbicide use during cash crop seasons and tillage operations. Triticale had the lowest seedbank density (9,487 seeds m−²) and higher diversity (Shannon Index 6.9) compared to WF (28,543 seeds m-² and 4.1, respectively). Furthermore, stochastic analysis revealed a lower risk of enlarging weed seedbanks in TRIT compared to WF (for seed densities above 900 seeds m−2). Moreover, management practices (CCs, cash crop sowing, termination/harvest) synchronised with weed seed production and germination likely contributed to the decreasing seed density of species including Portulaca oleracea and Chenopodium album, which were reduced by 90 and 80 %, respectively, by the study’s end. Over three years, autumn/winter and indifferent weed seed densities increased 4.2 times more in WF and RCM (22,638 seeds m−²) than in TRIT. This may be due to the varying growth rates among CC species in RCM, whereas TRIT consistently established rapidly, potentially outcompeting weeds until termination. Fallow periods between cash crops may increase weed species linked to that season and future crop–weed interference in varied crop rotations. Introducing CCs can mitigate this effect, although the choice of CC species may influence the extent of the impact.

Crop Safety and Weed Control of Foliar Application of Penoxsulam in Foxtail Millet.

Grass damage has become an important factor restricting foxtail millet production; chemical weeding can help resolve this issue. However, special herbicides in foxtail millet fields are lacking. Penoxsulam has a broad weed control spectrum and a good control effect. In this project, Jingu 21 was used as the test material, and five different concentrations of penoxsulam were used for spraying test in the three-five leaf stage. In this experiment, the effects on the growth of foxtail millet were discussed by measuring the agronomic characters and antioxidant capacity of foxtail millet after spraying penoxsulam. The results showed that: (1) penoxsulam is particularly effective in controlling Amaranthus retroflexus L. (A. retroflexus) and Echinochloa crus-galli (L.) Beauv. (E. crus-galli), but is ineffective in controlling Chenopodium album L. (C. album) and Digitaria sanguinalis (L.) Scop. (D. sanguinalis); (2) the stem diameter, fresh weight, and dry weight of the above-ground parts decreased with the increase in spraying amount; (3) as the spraying dosage increased, the superoxide (SOD), peroxidase (POD), and catalase (CAT) activities in the foxtail millet initially increased and subsequently decreased; the malonaldehyde (MDA) content increased. Our experiment found that 1/2X and 1X spraying dosages had certain application value in controlling gramineous weeds in foxtail millet field. Other spraying dosages are not recommended as they may harm the crops. Our findings provide reference for identifying new herbicides in the foxtail millet field.

Resistance to ACCase and ALS-inhibiting herbicides detected in targeted sampling of Lolium rigidum (rigid ryegrass) populations from cereal crops in Morocco, Algeria, and Tunisia

Lolium rigidum Gaud. (rigid ryegrass) is one of the most widespread weeds in cereal crops in Morocco, Algeria and Tunisia. This weed has evolved resistance to various herbicide modes of action in this region. ACCase and ALS inhibiting herbicides are mainly used in the major-cereal growing regions to control rigid ryegrass. Through a questionnaire, regions where farmers reported less control of herbicide treatments were registered in the three Maghreb countries. Registered fields were visited for collection and 75 field populations were screened with two ACCase and two ALS herbicides. Target site resistance (TSR) was diagnosed using Illumina Next Generation Sequencing (NGS) technology. The sensitivity bioassay results revealed over 60% of sampled populations to be resistant to pinoxaden and/or clodinafop and about 40% to be resistant to iodosulfuron + mesosulfuron and/or pyroxsulam. In addition, 53% of populations displayed resistance (R) to the two herbicide modes of action tested among the regions. In total, 16 ACCase and 11 ALS mutant alleles were identified, carrying out an amino-acid substitution and conferring herbicide resistance in 3700 of the analyzed plants. Most ACCase and ALS mutations were detected at codons Ile1781 and Pro197, respectively. Not only does this study demonstrate the presence of both cross and multiple resistance, it also highlights the non-ACCase and non-ALS -based resistance mechanisms that could confer resistance to herbicides with different modes of action which complicates the resistance management strategies. In the three Maghreb countries, this challenge is even more prominent due to few modes of action being available for rigid ryegrass control due to low-cost market and the prevalence of generic herbicides.

Significance of Insuring Herbicides for Stabilization of Weed Control Effectiveness and Quality when Using Betanals-Generics for Sugar Beet

In the field in 2014–2020, three-component herbicides of betanal generics were tested against juvenile dicotyledonous weeds in sugar beet crops to compare with the effectiveness of the use of the original herbicide Betanal Expert of (BEOF) at application rate of 1.0 l/ha. It is shown that the stability of dilute emulsions of generic betanals depended on the characteristics of the structure and dispersion of working solutions, the ability to crystallize active substances, and reactions to various environmental conditions. The BEOF herbicide in the application rate of 1.0 l/ha differed from generic betanals in the same application rate by a higher effect on weeds. The weeds that formed 2 real leaves showed phase resistance to generic betanals more noticeably. The effectiveness of BEOF on weeds in the cotyledon phase was 6–8% higher than that of generics, and 18% higher when treating weeds in the phase of 2 real leaves. It was found that in the temperature range of 19–22°C, the efficiency of generic betanals was closest to the efficiency of the original BEOF. To stabilize the generic betanals efficacy on weeds with the original BEOF 1.0 l/ha, their application rate was increased by 15–20%. A mixture of generic betanals with the insurance herbicides Mitron and Caribou, applied 3 times in the recommended application rates in accordance with the phase of development of sugar beet, provided high purity of sowing and crop yield at the level of the control group with manual weeding. Herbicides, in addition to broad-leaved dicotyledonous weeds, effectively suppressed young plants of aspens and field bindweed. The insurance herbicides Mitron and Caribou offset the disadvantages of generic betanals when used together in the fight against weeds in sugar beet crops.

The Potential of Deleterious rhizobacteria to Control Primary Weed <i>Echinochloa </i>sp. on Rice

Deleterious rhizobacteria (DRB) is one of the rhizobacteria that can be used as a bioherbicide and can stimulate plant growth. The objectives that can be obtained from this study are to determine the potential of DRB on the growth of weeds Echinochloa crusgalli and Echinochloa colona on rice. Variables observed in this study were identification of secondary metabolites, measurement of weed sprouts, percentage effectiveness of bacterial isolates against weed seeds, normal sprouts, abnormal sprouts, fresh seeds that did not grow and dead seeds. The aim of this study is to explore biological agents that can be used to control the main weeds of rice crops. This candidate could be a recommendation for environmentally friendly controls. Exploration of the DRB group was obtained by collecting soil samples around the roots of rice crops. Then isolate it, identify as morphologically and physiologically, and test it in vitro studies. The results showed that DRB had the potential to control weed growth and could stimulate the growth of rice. The application of PFA and PFB isolates had a significant effect on inhibiting the length of weed roots and buds, the average percentage of control effectiveness > 80-90%. Novelty in this study could be found as candidate groups of DRB bacteria with specific locations to control the weed Echinochloa sp. on rice crops. For society, this research could be an alternative to reduce dependence on synthetic herbicides . DRB has the potential to be formulated into a bioherbicide to control weeds.

Reducing vulnerability to climate change among millet and sorghum farmers in Ghana: interrogating the contribution of climate-smart agriculture in northwestern Ghana

Reducing vulnerability of smallholder farmers to climate change is a global issue. One approach viewed as important in reducing farmers’ vulnerability to climate change is Climate-Smart Agriculture (CSA). CSA is often seen as an approach to redefine, reposition and sustainably manage agriculture. Given the importance of CSA practices in sustaining the food needs of many farm households in sub-Saharan Africa and Ghana, this study investigates CSA practices that were introduced to farmers by Center for Indigenous Knowledge and Development (CIKOD), interrogates the contributions of CSA to reducing farmers vulnerability to climate change and established the relationship between CSA and climate change adaptation. The study employed a mixed method approach, using 146 smallholder millet and sorghum farmers. Questionnaire and interviews were used to generate primary data for analysis. Descriptive statistics, involving Chi-square test and relative importance index were used to analyze the questionnaire while thematic analytical approach was used to analyze the interviews. The results of the study revealed that CSA practices such as crop rotation, weed control, contour farming, and land rotation are deployed by smallholder farmers to respond to drought, dry spell and flood in the Municipality. Asset holding capacity, credit, access to climate information, and extension services were found to be key determinants of farmers’ adoption of CSA practices. The study recommends the need for the Ministry of Food and Agriculture to provide some technical support to smallholder farmers to successfully adopt these practices for sustainable farming. Again, the study recommends the need for non-governmental organizations and development partners, which over the years have shown interest in promoting CSA practices among farmers, to continuous to support and promote the adoption of CSA by farmers.

Assessment of florpyrauxifen-benzyl in water-seeded rice systems as affected by application timing

Florpyrauxifen-benzyl (FPB) is a novel auxin mimic rice herbicide used to control selected grasses, sedges, and broadleaves. Field experiments were conducted in 2020–2022 to 1) characterize the effects of FPB on rice crop safety and weed control when applied alone or in a mixture, 2) determine the FPB application timing to optimize smallflower umbrella sedge (SMF) control, and 3) evaluate the effect of late season application on rice flower sterility. In the first study, FPB was applied alone at 15, 30, and 60 g ai ha−1 and in mixture with bispyribac-sodium, penoxsulam, and propanil. FPB applied alone at 30 g ha−1 at 4–5-leaf (LF) rice stage controlled more than 80% of watergrasses, ricefield bulrush, and SMF and more than 99% of all broadleaf weeds at 28 days after treatment (DAT). The mixture treatments of FPB plus bispyribac-sodium applied at maximum use rate had the greatest grass weed control whereas, FPB plus propanil at the maximum use rate provided the greatest sedge control. In the second study, FPB at 40 g ha−1 was applied at 1-LF, 10-, 15-, 20-, and 25-cm tall SMF, where treatments controlled 95%, 86%, 89%, 87%, and 85% of SMF at 42 DAT, respectively. In the third study, FPB at 40 and 80 g ha−1 rate was applied at rice panicle initiation (PI) and 50% flowering (FL) growth stages. While the weed control was more than 90% at 42 DAT for all applications, the FL stage application caused 26% and 35% rice panicle blanking at 40 and 80 g ha−1 rate, respectively. This research suggests, the window of FPB application should be from 2-LF rice to rice PI stage to ensure crop safety and highest weed control.

The Influence of Seeding Rates on Crop Infestation and Safflower Yield

Background: Safflower is an oil seed crop that can form seeds in extreme conditions, so it can be used as an alternative to sunflower because their growing technologies are similar. Weeds cause significant damage to the safflower crop. The safflower crop does not tolerate chemicals used to control weeds, so the study was devoted to alternative methods of weed control in its crops, namely the effect of seeding rates on weed infestation and seed yield. The goal is optimal seeding rate and its effect on weed infestation of safflower crops. Methods: The experimental site was laid out on the right bank of the Volga River, Kamyshinsky district, Volgograd region, in a dry steppe zone of chestnut soils with a hydrothermal coefficient of 0.6-0.4. Safflower seeds were sown with three seeding rates: 25, 30, 35 kg/ha in triplicate, with row spacing of 15 cm. The experimental results were presented graphically and processed by dispersion analysis. Result: The research results showed that in the area with a sowing rate of 35 kg/ha of viable seeds there was the least weed in the safflower crops, and the seed yield was higher than in other areas with lower sowing rates. Statistical analysis determined that the seeding rate has a 51.1% effect on safflower yield.

Cytogenics, morphology and viability of Borreria spinosa (Rubiaceae) pollen grains

Introduction: Borreria spinosa is a herbaceous plant considered a weed in agricultural crops, although it also has potential in apiculture. Despite its agronomic importance, its cytogenetic and palynological traits are poorly known. Objective: To do the cytogenetic characterization of B. spinosa, describe the morphology of its pollen grains, and estimate their potential viability. Methods: We collected plant material in Santiago del Estero, Argentina, in May 2017 and used classical methods (8-hydroxyquinoline and Farmer for mitosis and meiosis; viability with Müntzing; pollen morphology with nonacetolysed and acetolysed techniques, and SEM). Results: B. spinosa has a chromosome number of 2n = 56, with a karyotype of 46 m + 10 sm. Meiotic abnormalities mainly include chromosomes outside the equatorial plate, lagging chromosomes, and cytomixis. Pollen grains are small to medium-sized, suboblate to oblate-spheroidal, with a viability of 70%. This is a tetraploid species, most chromosomes are metacentric or submetacentric; and it has irregular meiotic behavior and cytomixis, with concomitant low viability in pollen grains. Conclusion: In B. spinose, pollen grains have similar characteristics to other species of the genus Borreria.

Nutrient dynamics study and yield optimization for soybean through integrated nutrient and weed management

Soybean production faces many constraints with several factors, such as biotic and abiotic factors, and the crop management practices where inadequate nutrient management leads to a decline in production potential of the crop. Among the biotic factors, exploitation of resources by weeds not only causes a decline in production but also decreases the crop quality. Managing the weeds during the critical period of crop weed competition plays outstanding role in maximizing soybean production. In order to study the influence of integrated nutrient and weed management on nutrient dynamics and yield optimization of soybean an experiment was conducted in Split Plot Design with three nutrient management treatments in main plot {100% recommended dose of fertilizer (RDF), 75% RDF + 25% N through farmyard manure (FYM) + Phosphate solubilizing bacteria (PSB) and 50% RDF + Rhizobium + PSB} and five weed management treatments in the sub-plot (Hand weeding at 15, 30 and 45 DAS, Mechanical weeding at 20 and 40 DAS, Pendimethalin @ 1 kg a.i. ha−1 PE fb Hand weeding at 30 DAS, Propaquizafop @ 0.075 kg a.i. ha−1 PoE fb Hand weeding at 45 DAS, and Weedy check as control). The results indicated that application of 75% RDF + 25% N through FYM + PSB recorded the highest seed yield, nutrient content in seed and uptake of N, P, K, and S in the seed and stover, microbial population, and soil nutrient status. Highest partial factor productivity was recorded under 50% RDF + Rhizobium + PSB. Under weed management, hand weeding recorded the highest growth, yield attributes and nutrient content, but was found to be at par with Pendimethalin @ 1 kg a.i. ha−1 PE fb Hand weeding at 30 DAS and Propaquizafop @ 0.075 kg a.i. ha−1 PoE fb Hand weeding at 45 DAS. Application of 75% RDF + 25% N through FYM + PSB and pendimethalin @ 1 kg a.i. ha−1 fb hand weeding at 30 DAS proves to be an effective strategy for soybean cultivation. The experiment was conducted at the experimental farm of School of Agricultural Sciences, Nagaland University, Medziphema, India.

Rotation with Soybean Improved Weed Control and Foxtail Millet Yield

Foxtail millet is an important characteristic grain crop in northern China. However, weeds compete seriously with foxtail millet and have long been a biological factor that has plagued foxtail millet production. Rotation requires determining the species and sequence of crops, and reasonable rotation has many benefits for agriculture, including reducing the damage by weeds. In order to clarify the combination effects of foxtail millet–soybean rotation sequence and herbicide on weed control and crop yield, fixed-position experiments were designed in three growing seasons. Foxtail millet and soybean were planted following the sequence below in successive years (FFF, foxtail millet–wheat–foxtail millet–wheat–foxtail millet; SFF: soybean–wheat–foxtail millet–wheat–foxtail millet; SSF, soybean–wheat–soybean–wheat–foxtail millet; SSS, soybean–wheat–soybean–wheat–soybean), and weed density, biodiversity, weed seedbank, and crop yield were examined and analyzed. The results showed that the average weed density of SFF and SSF was reduced by 61.7% and 66.3% compared with FFF in the three years and by 16.5% and 26.6% compared with SSS, separately. Foxtail millet–soybean rotation (SFF and SSF) increased the species richness and the Margalef species richness index of the weed community and reduced the Simpson index compared with the continuous foxtail millet and the continuous soybean cropping (FFF and SSS). The weed seedbank of SFF and SSF was 45.7% and 55.8% smaller than that of FFF and increased by 92.7% and 56.7% compared with SSS, respectively. The weed density in the FFF treatment was significantly correlated with the 0–5 cm grass seedbank size, while there was no significant correlation in the other three treatments. Benefiting from the lower weed damage intensity, the yield of foxtail millet in SFF and SSF increased by 54.05% and 221.81% compared with FFF, respectively. The research results revealed that both SFF and SSF can effectively reduce the damage of weeds and help improve biodiversity. SSF has a higher weed control effect and higher foxtail millet yield than SFF. This study contributes to the understanding of crop–weed interactions in foxtail millet–soybean rotation and can be applied to areas with similar environments.

Increased winter‐killed cover crop seeding rate may not increase soil health outcomes

AbstractImplementing soil conservation practices can begin to restore degraded soils, improve soil health, and increase overall ecosystem services. Cover cropping is an effective strategy to rebuild soil quality through decreased erosion and increased residue inputs, which can help build soil organic matter. Cover crop seeding rate may have a positive relationship with ecosystem services; however, it is unknown whether this is realized at or below the recommended cover crop seeding rate. The goal of this study was to identify the relationship between cover crop seeding rate and soil health biogeochemical measures across the growing season using five oat (Avena sativa L.)–pea (Pisum sativum L.) cover crop treatments of 0%, 25%, 50%, 75%, and 100% the industry standard seeding rate at the University of Massachusetts Amherst Research Farm. Soils were tested for soil carbon (C), nitrogen (N), and microbial measures at winter kill, spring thaw, post‐planting, and succeeding cash crop harvest. Soil measures did not vary among seeding rates, but total ground cover was consistent among treatments due to weed growth. Soil health measures vary seasonally reflecting soil microbial activity. Our study provides initial evidence that soil biogeochemical responses do not respond to increased seeding rate within one growing season when the resulting groundcover—cover crop biomass plus weeds—is consistent across seeding rates, but sampling date can influence the magnitude of soil biological and chemical soil health metrics.

Effect of crop establishments methods, tillage practices and weed management practices in rice on growth indices of crops under rice-chickpea cropping system

Effect of crop establishments methods, tillage practices and weed management practices in rice on growth indices of crops under rice-chickpea cropping system

Implementing Digital Multispectral 3D Scanning Technology for Rapid Assessment of Hemp (Cannabis sativa L.) Weed Competitive Traits

The economic significance of hemp (Cannabis sativa L.) as a source of grain, fiber, and flower is rising steadily. However, due to the lack of registered herbicides effective in hemp cultivation, growers have limited weed management options. Plant height, biomass, and canopy architecture may affect crop–weed competition. Greenhouse experiments conducted at the joint Clemson University Coastal Research and Education Center and USDA-ARS research facility at Charleston, SC, USA used 27 hemp varieties, grown under controlled temperature and light conditions. Weekly plant scans using a digital multispectral phenotyping system, integrated with machine learning algorithms of the PlantEye F500 instrument, (Phenospex, Heerlen, Netherlands) captured high-resolution 3D models and spectral data of the plants. Manual and scanner-based measurements were validated and analyzed using statistical methods to assess plant growth and morphology. This study included validation tests showing a significant correlation (p < 0.001) between digital and manual measurements (R2 = 0.89 for biomass, R2 = 0.94 for height), indicating high precision. The use of 3D multispectral scanning significantly reduces the time-intensive nature of manual measurements, allowing for a more efficient assessment of morphological traits. These findings suggest that digital phenotyping can enhance integrated weed management strategies and improve hemp crop productivity by facilitating the selection of competitive hemp varieties.