Weed Management In Soybean Research Articles

Comparative studies of knapsack, boom, and drone sprayers for weed management in soybean (Glycine max L.)

The study titled, "Comparative Evaluation of Knapsack, Boom, and Drone Sprayers for Weed Management in Soybean (Glycine max L.)" was carried out during the Kharif season 2021-22 at an experimental farm affiliated with the Department of Agronomy, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani. The primary objective was to evaluate the comparative efficacy of various sprayers in controlling weeds in soybeans and their work efficiency. The Randomized Block Design (RBD) included ten treatments of pre-emergence (PE) and post-emergence (POE) herbicides applied by knapsack, boom, and drone sprayers. Pendimethalin 30% EC @ 750 g a.i ha−1 was used for pre-emergence herbicide application, and Imazamox 35% EC + Imazethapyr 35% WG @ 70 g a.i ha−1 were used for post-emergence. These treatments were tested on soybean Monocot and Dicot weed count, weed dry weight, weed index, and weed control efficiency. The sprayers were compared for time, water, labor, herbicide, and overall work efficiency. A knapsack sprayer showed the best results for pre- and post-emergence herbicide application, with the lowest weed count, dry weight, control efficiency, and weed index. Boom and drone sprayers followed in effectiveness. Herbicide application was faster with the drone sprayer than with hand weeding, cultural practices, boom sprayer, and knapsack sprayer. Compared to knapsack and boom sprayers, the drone sprayer used less water and labour. Drone sprayers work most efficiently, followed by boom and knapsack sprayers. This study focuses on the prevalence of herbicides and their impact on non-target ecosystems. It aims to develop mitigation strategies by optimizing spraying efficiency and reducing herbicide usage during pre and post emergence. The dissemination of efficient weed management practices that reduce environmental impacts and increase the efficiency of soybean cultivation is consistent with Sustainable Development Goal 15: life on land.

Weed management strategies in Soybean (Glycine max) — A review

Soybean (Glycine max L.) being a rainy season crop, faces severe infestation of kharif weeds. Since the crop suppresses weeds due to its dense canopy at later stages of growth, the control of weeds has received very little attention. Weeds offer severe competition to crops during the early stage of growth. The critical crop weed competition period in soybean varies from 15–45 days after sowing (DAS) depending upon location and prevailing environmental conditions. Weeds cause a 26–84% reduction in the yield depending upon the types and intensity of weeds, besides impairing the quality of the produce. Different methods of weed management in field crops include preventive, cultural, mechanical, chemical, biological, and biotechnological means. Weed control through a physical approachachieved by hand weeding at 20 and 40 DAS (twice) is ineffective due to the continuous rainfall and high labour wages. The use of herbicides for the control of weeds has gathered momentum in recent years. Weed control through the integration of herbicides with cultural weeding is a paying proposition. Double knock application of one preemergence herbicide followed by application of post-emergence herbicides, solves the problem of labour scarcity encountered by the farmers. However, the timely application of different weed management tactics has a crucial role in achieving the desired target. Killing one or two flushes before seeding a crop and immediate cultivation of field after harvest to destroy survivors has an added advantage. An effort has been made in this article to review the work done on weed management in soybean

Control period and economic threshold level of glyphosate tolerant weeds in 2.4-D resistant soybean

Weed densities, species, costs of control, crop value and interference periods should be considered for weed management. With this regard, three experiments were carried out to evaluate weed control periods and weed density in a new soybean cultivar. In ths first trial, control efficacy was measured by visual phytotoxicity of four weed species I. hederifolia, E. heterophylla, Conyza spp. and R. brasiliensis using four different herbicides with two doses each: glyphosate (720 and 1,440 g ea ha-1), 2.4-D (670 and 1,340 g ea ha-1), glufosinate (400 and 600 g ea ha-1) and glyphosate + 2.4-D (410 + 390 and 820 + 780 g ea ha-1). Herbicides were sprayed in an entirely randomized 4x8+1 factorial scheme with six repetitions. In the second experiment, 2,4-D-resistant soybean growth was measured under increasing densities of the same weeds (21 plants m² vs 21, 42, 84, 168 and 336 plants m²). This experiment was conducted under entirely randomized design with 25 treatments with four repetitions. Critical level of damage and economic threshold level of each weed species in soybean were measured using non-linear regressions. In a third experiment, weed with soybean were submitted to increasing periods of control and coexistence (7, 14, 21, 28, 35, 49 and 70 days after soybean emergence, plus two control treatments). Glufosinate and glyphosate+2.4-D (820 + 780 g ea ha-1) showed greater weed control than glyphosate alone (720 g ea ha-1). The yield loss of 0.85, 2.12, 5.71 and 34.24% were found for each weed of E. heterophylla, I. hederifolia, R. brasiliensis and Conyza spp., coexisting with soybean. There was a soybean grain yield loss of 50% in the weedy treatment. Soybean weed management should occur between 18thand 48th days after its emergence. Economic threshold level on soybean yield suggested is below one plant of Conyza spp. and R. brasiliensis per m-². The use of glufosinate and glyphosate+2,4-D provides a greater flexibility of herbicide use for farmers

Performance of herbicides on effective weed management in soybean (Glycine max) crop

Field experiment was conducted to study the efficacy of different post-emergence herbicides in the soybean (Glycine max (L.) Merr.). The selected herbicides were applied individually or in combination in soybean. A series of experiments were conducted during 2013 to 2017. Application of quizalofop-p-ethyl + chlorimuron ethyl and fenoxaprop-p-ethyl + chlorimuron ethyl along with surfactant at 15 days after sowing (DAS) were found effective herbicides for control of broad leaf weed and grasses in soybean crop. It was observed that post-emergence application of quizolofop-p-ethyl (50 g a.i.) + chlorimuron ethyl (6 g a.i./ha) significantly reduce the weed population (8/m2), weed dry matter (2.3), weed index (0) and highest weed control efficiency (92.9%) and grain yield (1.77 t/ha) at 45 DAS followed by fenoxaprop-p-ethyl (50 g a.i.) + chlorimuron ethyl (6 g a.i./ha) compared to other treatments. Application of quizolofop-p-ethyl (50 g a.i.) + chlorimuron ethyl (6 g a.i./ha) was found to minimize the loss (44.06%) caused by weeds and there by improve the uptake of water, air, and nutrition by the crop plants. Further, application of quizalofopp- ethyl + chlorimuron ethyl + surfactant enhanced the number of nodule/plant (52.00), nodule diameter (5.00 mm) and nodule weight (187.2 mg/plant) followed by fenoxaprop-p-ethyl + chlorimuron ethyl + surfactant as compared to other treatments. Highest yield was recorded in the plants treated with quizalofop-p-ethyl + chlorimuron ethyl + surfactant in combination compared to other treatments. Quizalofop-p-ethyl and fenoxaprop-p-ethyl + chlorimuron ethyl along with surfactant were found to highly comparable in terms of price and yield compared to other methods of weed control including hand weeding. This combination can be recommended for the control of both broad and narrow leaf weed the soybean crop.

Evaluating the allelopathic effects of sorghum aqueous extract tank mixed with herbicide for weed management in soybean

Evaluating the allelopathic effects of sorghum aqueous extract tank mixed with herbicide for weed management in soybean

Pre and post - emergence herbicides with cultural practices on weed management in soybean - pigeonpea intercropping system under middle Gujarat conditions

To study the “pre and post-emergence herbicides with cultural practices on weed management in soybean-pigeonpea intercropping system under middle Gujarat condition”, an experiment was conducted at Agriculture Research Station, Anand Agricultural University, Derol, Dist: panchmahal, Gujarat, India during kharif seasons of the years 2017-18 and 2018-19. Ten treatments for weed management were studied in randomized block design with four replications. Result of field experimentation, it seems quite logical that potential production, profit and economic weed management can be achieved in soybean - pigeonpea intercropping system by interculturing + hand weeding at 20 & 40 DAS or post-emergence application of imazamox 35% + imazethapyr 35% (Pre mix)70 g ha-1PoE fb interculturing + hand weeding at 30 DAS.

Timing of weed management and yield penalty due to delayed weed management in soybean

Background: Weed interference is a major limiting factor for economically viable soybean production. Appropriate timing of weed management would enable farmers to make more efficient use of resources for weed management. Objective: The objective of this study was to determine the critical period for weed competition and appropriate timing of weed management for optimum yield of soybean. Methods: The treatments consisted of periods of weed infestation and weed removal for the first 14, 28, 42 and 56 days after sowing (DAS), and till harvest in a randomized complete block design with three replications in 2016 and 2017. Results: Soybean yields in both years ranged from 914-945 kg ha-1 with no weed control to 1,984-2,127 kg ha-1 in the weed-free plots; a yield loss of 53-56. Weed infestation for the first 14 DAS had no detrimental effect on growth and yield of soybean provided the weeds were subsequently removed. Increasing period of weed interference from 14 to 42 DAS resulted in a steady decline in growth and yield of soybean. Yield losses equivalent of 32-37 kg ha-1 resulted for each day that weed control was delayed between 14 and 42 DAS. Subsequent weed control after 42 DAS did not improve growth and yield significantly, nor obviate yield depression of the crop compared to crop weed-infested till harvest. Conclusions: Results indicated that the critical period of weed competition in soybean was between 14 and 42 DAS. Hence soybean should be maintained weed-free during this period to avoid high yield loss.

Annual weed management in isoxaflutole-resistant soybean using a two-pass weed control strategy

AbstractTransgenic crops are being developed with herbicide resistance traits to expand innovative weed management solutions for crop producers. Soybean with traits that confer resistance to the hydroxyphenylpyruvate dioxygenase herbicide isoxaflutole is under development and will provide a novel herbicide mode of action for weed management in soybean. Ten field experiments were conducted over 2 years (2017 and 2018) on five soil textures with isoxaflutole-resistant soybean to evaluate annual weed control using one- and two-pass herbicide programs. The one-pass weed control programs included isoxaflutole plus metribuzin, applied PRE, at a low rate (52.5 + 210 g ai ha−1), medium rate (79 + 316 g ai ha−1), and high rate (105 + 420 g ai ha−1); and glyphosate applied early postemergence (EPOST) or late postemergence (LPOST). The two-pass weed control programs included isoxaflutole plus metribuzin, applied PRE, followed by glyphosate applied LPOST, and glyphosate applied EPOST followed by LPOST. At 4 weeks after the LPOST application, control of common lambsquarters, pigweed species, common ragweed, and velvetleaf was variable at 25% to 69%, 49% to 86%, and 71% to 95% at the low, medium, and high rates of isoxaflutole plus metribuzin, respectively. Isoxaflutole plus metribuzin at the low, medium, and high rates controlled grass species evaluated (i.e., barnyardgrass, foxtail, crabgrass, and witchgrass) 85% to 97%, 75% to 99%, and 86% to 100%, respectively. All two-pass weed management programs provided 98% to 100% control of all species. Weed control improved as the rate of isoxaflutole plus metribuzin increased. Two-pass programs provided excellent, full-season annual grass and broadleaf weed control in isoxaflutole-resistant soybean.

Economics of row spacing and integrated weed management in soybean (Glycine max L.)

The high cost of cultivation and weed management are major limiting factors to increasing soybean productivity and net returns. Field experiments were conducted in 2016 and 2017 at the Teaching and Research Farm of the Federal University of Agriculture, Abeokuta to evaluate the economic performance of different row spacings and integrated weed management system in soybean. Three row spacings (50, 75 and 100 cm) as the main plots and six weed control methods and a weedy check as sub-plot treatments were accommodated in a split-plot arrangement of a randomized complete block design with three replications. There was a significant reduction in weed biomass with a reduction in row spacing from 100 cm to 75 cm and 50 cm. Furthermore, the cost of production, grain yield and gross profit increased with a reduction in row spacing from 100 to 75 and 50. When soybean was sown at 50-cm row spacing, the application of Probaben 400EC (metolachlor 20% w/v + prometryn 20% w/v) or Butachlor 60EC (butachlor) at 2.0 kg a.i/ha each followed by supplementary hoe-weeding at 6 weeks after sowing (WAS) resulted in the highest yield of 2301-2484 kg/ha and total revenue of 2129-1972 $/ha. Conversely, three hoe-weedings resulted in the highest yield of 2155-2081 kg/ha and total revenue of 1848-1783 $/ha for crops grown at 75- and 100-cm row spacings. Despite the higher yield and revenue obtained with three hoe-weedings for crops grown at 75- and 100-cm row spacings, the gross profit and benefit-cost ratios obtained were lower than those obtained with herbicide treatments applied alone or followed by supplementary hoe-weeding. In terms of profitability, soybean planted at 50-cm row spacing and treated with Probaben 400EC at 2.0 kg a.i/ha followed by supplementary hoe-weeding gave the highest gross profit of 1479 $/ha. Two or three hoe-weedings in soybean planted at narrow-row (50 cm) spacing did not guarantee the highest yield, but rather increased the cost of weed control. This study suggests that narrow-row spacing (50 cm) and pre-emergence herbicides will help to reduce the number of hoe-weedings and consequently the high cost of production required for optimum yield and increase profitability in soybean production.

Integrated weed management in soybean

A field experiment was conducted during 2010 to 2012 for three years at Agricultural Research Station, Karad Maharashtra to find out the suitable integrated weed management method in soybean. Post-emergence application of quizalofop-ethyl at 0.05 kg/ha + chlorimuron-ethyl at 0.009 kg/ha at 15 days after seeding (DAS) + hand weeding at 30 DAS, recorded lowest weed biomass (38.1 g/m2) with higher weed control efficiency (62%) and lower weed index (8.0). The some treatment also recorded the highest seed yield and net returns with lower weed index (8.0) in soybean.

Promising post-emergence herbicides for effective management of broadleaved weeds in soybean

Promising post-emergence herbicides for effective management of broadleaved weeds in soybean

Candidate Tools for Integrated Weed Management in Soybean at the Northern Frontier of Production

AbstractThe development of early-maturing soybean [Glycine max(L.) Merr.] varieties has led to an increase in soybean production in canola (Brassica napusL.)-dominant crop rotations in western Canada. Herbicide-resistant (HR) volunteerB. napuscan be difficult to manage in HR soybean using herbicides alone. In 2013 and 2014, four field experiments were conducted in Manitoba, Canada, to evaluate soybean row spacing, seeding density, nitrogen supply, and interrow tillage as candidate nonchemical weed management tools for an integrated program to manage volunteerB. napusin soybean. Among treatments and sites, volunteerB. napusproduced about 830 seeds plant−1and resulted in large seedbank inputs (averaging about 20,300 seeds m−2). VolunteerB. napusseedling recruitment differed among sites, and resulted in two distinct classes of sites based on average seedling densities of 39 and 89 plants m−2. Weed management tools were more effective at the sites with higher volunteerB. napusdensities. At these sites, soybean yield was greater when using an increased soybean-seeding density (44% greater yield using a seeding density of 682,500 vs. 455,000 seeds ha−1) or interrow tillage (36% greater yield with vs. without using interrow tillage). Soybean row spacing (19 vs. 38 vs. 76 cm) did not affect soybean yield, unless the reduction in row spacing was combined with an increased seeding density (65% greater yield with narrow-row soybean seeded at 682,500 vs. wide-row soybean seeded at 455,000 seeds ha−1). At the sites with higher volunteerB. napusdensities, seed production of canola volunteerB. napuswas greater when nitrogen fertilizer was applied to simulate an environment with greater nitrogen supply (77% greater number of volunteerB. napusseeds produced with vs. without broadcast application of 23 kg N ha−1urea). In northern climates, seeding soybean at increased densities using narrow-row spacing in fields with limited soil inorganic nitrogen and using interrow tillage in wide-row production systems are effective strategies that could augment chemical weed management in an integrated program for management of volunteerB. napus, and perhaps also other competitive early-season weeds.

A Midsouthern Consultant’s Survey on Weed Management Practices in Soybean

AbstractSoybean consultants from Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee were surveyed in 2016 to assess weed management practices and the prevalence of herbicide-resistant weeds in midsouthern U.S. soybean production. The consultants surveyed represented 13%, 28%, 8%, 16%, and 5% of the total soybean area planted in Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee, respectively. Of the total scouted area, 78% of the consultants said their growers planted glyphosate-resistant soybean in 2016, with 18% planting glufosinate-resistant (LibertyLink®), primarily due to familiarity with and cost of the technology. Although 94% of the consultants determined that glufosinate was most effective on killing Palmer amaranth, the primary concern associated with controlling herbicide-resistant weeds was the associated cost, followed by return profit and time constraints. Palmer amaranth, morningglory species, horseweed, barnyardgrass, and Italian ryegrass were the five most problematic weeds in soybean across the five states. Palmer amaranth was the most problematic and important weed in each state individually. The increased concern (77% of consultants) with this species was attributed to the rising concern with and occurrence of protoporphyrinogen oxidase–resistant Palmer amaranth. Consultants were of the opinion that more research was needed on cover crops and the new traited technologies in order to improve weed management in soybean.

Single and sequential applications of dicamba for the control of glyphosate-resistant common ragweed in glyphosate- and dicamba-resistant soybean

Confirmation of glyphosate-resistant (GR) weeds in southwestern Ontario has led to a change in weed management practices, particularly in soybean. Registered soil-applied herbicides have been identified that have activity on GR common ragweed; however, due to the long emergence period of common ragweed, additional postemergence options are required. The recent development of glyphosate- and dicamba-resistant soybean (Roundup Ready Xtend soybean) allows for the preplant and postemergence application of dicamba. Three field studies were conducted in Ontario, Canada, in a field with confirmed GR common ragweed. Glyphosate-resistant common ragweed interference resulted in 75% yield loss in soybean compared with the weed-free check. At 4 wk after application, dicamba tank-mixed with glyphosate applied preplant only, postemergence only, or preplant followed by postemergence controlled GR common ragweed up to 94%, 87%, and 99%, respectively. The availability of dicamba for use in glyphosate- and dicamba-resistant soybean will provide an additional mode of action for weed management in soybean.

Weed Control in Soybean with Preemergence‐ and Postemergence‐applied Herbicides

Core Ideas Herbicide premixes provided good (>90%) broadleaf and grass weed control in Nebraska. Preemergence‐applied herbicide premixes with different sites of action will help manage resistance weeds. Preemergence‐applied herbicides should be a foundation for weed management in soybean. In the past 20 years, weed control in soybean (Glycine max) was mainly based on postemergence (POST) applications of glyphosate, which resulted in glyphosate‐resistant weeds. Herbicide‐resistant weeds warrants evaluation of new strategies for effective control. Therefore, the objective of this study was to evaluate the performance of herbicides applied preemergence (PRE) and POST on 11 agronomic weeds in eastern Nebraska. The study was conducted in 2014 and 2015 in Concord, NE. The best PRE‐applied treatments were metolachlor + imazethapyr, fomesafen + imazethapyr, flumioxazin + imazethapyr, and flumioxazin + metribuzin, which controlled broadleaf and grass weed species ≥90 and ≥80%, respectively. However, weed control with POST herbicides was more variable, ranging from 19 to 91%. The POST‐applied fomesafen and fomesafen + imazethapyr controlled ivyleaf morningglory (Ipomoea hederacea), common lambsquarters (Chenopodium album), common waterhemp (Amaranthus tuberculatus), and redroot pigweed (Amaranthus retroflexus) ≥85%. Greater soybean yields were achieved with most PRE‐applied herbicides and POST‐applied fomesafen + imazethapyr only. Metolachlor + imazethapyr, metolachlor, and fomesafen applied PRE protected soybean yields better than when applied POST. Results suggested that PRE‐applied herbicide mixtures of different sites of action are the base for controlling weeds and protecting soybean yields in eastern Nebraska.

High-Residue Cultivation Timing Impact on Organic No-Till Soybean Weed Management

A cereal rye cover crop mulch can suppress summer annual weeds early in the soybean growing season. However, a multi-tactic weed management approach is required when annual weed seedbanks are large or perennial weeds are present. In such situations, the weed suppression from a cereal rye mulch can be supplemented with the use of high-residue cultivators which can prolong the weed-free period during soybean growth. Research trials were conducted to determine the optimum timing of high-residue cultivation for weed control in rolled-crimped cereal rye mulches. Treatments included three cultivation timings with a high-residue cultivator: early (3-4 wk after soybean planting (WAP)), intermediate (5-6 WAP), and late (7-8 WAP), a weed-free and no-cultivation control. Crop and weed measurement included cereal rye biomass, weed biomass, soybean population and biomass, and yield. Cereal rye biomass was 50% lower and weed biomass was three times greater in 2011 than in 2010 and 2012 due to 2011 being a dry year. There was no significant effect of cultivation timing on soybean population when compared to no-cultivation or hand-weeded treatments. While cultivation reduced weed biomass by 67% compared to no-cultivation, soybean yield was only improved by 12% in early and late cultivation treatments and 22% in intermediate cultivation treatment when compared to no-cultivation. Effective strategies for improving weed management by integrating the use of a high-residue cultivator in no-till organic systems could help existing organic field crop producers to reduce tillage while also encourage adoption of organic crop production by conventional growers who prefer reduced-tillage systems. Unlike traditional organic cultivation equipment, therefore, optimal timing of cultivation should be delayed several weeks in organic cover crop-based no-till planted soybean production as compared to the typical tillage-based approach to ensure both weed control and optimal yield.

Bio-efficacy of flumioxazine for weed management in soybean and its residual effect on succeeding crops

Bio-efficacy of flumioxazine for weed management in soybean and its residual effect on succeeding crops

Managing weeds using crop competition in soybean [Glycine max (L.) Merr.

Soybean (Glycine max (L.) Merr.) is an important crop worldwide for both protein meal and vegetable oil. Soybean accounts for more than 50% of the global oilseed production. Weed infestation is a complex and regular threat to soybean production all over the world. To combat this threat, chemical, mechanical, and cultural methods are generally used. There has been a revived interest in weed suppression through improved crop competitiveness as an alternative aid in weed management. Different approaches could be utilized to increase crop competitiveness such as adjustment of row spacing, optimum seeding rate, and use of genotypes with high weed-competitive ability. During the past several decades, adoption of narrow row spacing has become increasingly popular among soybean growers primarily because of yield advantage and early canopy closure, which directly provides greater weed suppression. Adoption of narrow rows significantly reduces the density and biomass of late-season emerging weeds and delays the critical time for weed removal compared with wide rows. An increase in seeding density/plant population also suppresses weeds by earlier canopy closure, especially when combined with narrow row spacing. Competitive abilities of different soybean cultivars against different weed species are not consistent. Interseeding cover crops after establishment of soybean also can be a viable option for weed suppression as long as cover crops do not compete with soybean, or act as weeds themselves. Integrated weed management is considered to be the most effective approach for long-term and sustainable management of weeds in soybean. The objective of this article is to provide an overview of currently known cropping practices for improving soybean competitiveness against weeds.

Associação dos herbicidas diclosulam e glyphosate na dessecação visando o controle residual de plantas daninhas na cultura da soja

A associação dos herbicidas glyphosate e diclosulam na dessecação pode diminuir a presença de plantas daninhas por maior período, favorecendo assim o desenvolvimento e a produtividade das plantas de soja. Objetivou-se verificar a eficiência do herbicida diclosulam associado ao glyphosate, na dessecação para plantio direto da cultura de soja RR, cultivada no sistema plante e aplique. A cobertura vegetal presente foi Urochloa ruziziensis com 4,4 t ha-1, distribuída uniformemente sobre a área experimental. O delineamento experimental utilizado foi o de blocos ao acaso com três tratamentos e 4 repetições. Os tratamentos constituíram-se na aplicação de glyphosate a 1,2 kg ha-1 de equivalente ácido (e.a.) + diclosulam a 25,2 g ha-1 de ingrediente ativo (i.a.) em pré-semeadura da cultura sem a aplicação complementar, glyphosate a 1,2 kg ha-1 de e.a. + diclosulam a 25,2 g ha-1 de i.a. em pré-semeadura da cultura + glyphosate a 1,2 kg ha-1e.a. em complementação e glyphosate a 1,2 kg ha-1 de e.a. em pré-semeadura + glyphosate a 1,2 kg ha-1 de e.a. em complementação. Foram avaliados os seguintes parâmetros: reinfestação inicial e densidade relativa de plantas daninhas aos 31 dias após a dessecação, reinfestação de plantas daninhas no período da colheita, dificuldade de colheita mecanizada, número de vagens por planta, peso de 1000 grãos e produtividade de grãos. A associação do herbicida diclosulam ao glyphosate auxilia no manejo inicial da comunidade infestante no cultivo da soja, sem, no entanto, dispensar a aplicação complementar do herbicida glyphosate.

Energy budgeting of weed management in soybean

Energy budgeting of weed management in soybean