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The establishment of industrial hemp (Cannabis sativa L.) fields near row crops has raised concerns about the potential adverse effects of herbicide drift on hemp production. This study examined hemp susceptibility to drift of herbicides registered for use in corn and/or soybeans. Herbicide solutions (2,4-D, dicamba, glufosinate, glyphosate, imazethapyr, lactofen, mesotrione) were applied separately in the wind tunnel (3.6 m s−1 airspeed), simulating drift scenarios, with conventional TP95015EVS (TP) and air inclusion AI95015EVS (AI) flat fan nozzles calibrated to deliver 140 L ha−1 carrier volume at 230 kPa. Mylar cards and hemp plants (20–25 cm tall) were placed downwind up to 12 m. Spray deposition from mylar cards was quantified using fluorometry and hemp biomass was collected 21 post application. Results indicated the nozzle design influenced downwind deposition; 5% of spray deposits from the TP nozzle reached 5.9 m downwind versus 2.0 m for the AI nozzle. Glyphosate, glufosinate, and mesotrione caused the highest biomass reductions, with 50% reductions observed at 19.3 (inferred), 8.7, and 9.3 m downwind for TP nozzle, and 4.1, 4.0, and 2.9 m for AI nozzle. These findings suggest herbicide applications at airspeeds of 3.6 m s−1 or greater present a risk to nearby hemp fields. [ABSTRACT FROM AUTHOR]

Brassica carinata A. Braun (carinata) has become an important oil crop for biofuel production in subtropical regions. Carinata is highly sensitive to acetolactate synthase (ALS)‐inhibiting herbicides, limiting its introduction into existing crop rotations. The objective of the study was to develop carinata lines resistant to ALS‐inhibiting herbicides. A susceptible carinata line was crossed with a resistant Brassica napus L. line. Lines derived from those crosses were screened at high doses of imidazolinones, which allowed identifying five lines with high levels of resistance. Doses to reduce plant growth 50% (GR50) and cause 50% injury (ID50) were four to nine times greater than susceptible lines. Resistant lines exhibited cross resistance with halosulfuron (sulfonylurea). Resistance was confirmed under field conditions with doses 2X and 4X for imazethapyr and 4X–8X for halosulfuron of their respective label doses. While susceptible lines died, resistant lines exhibited no injury or growth reductions compared with nontreated controls. Sequencing of the ALS gene indicated that all resistant lines carried a Trp574Leu amino acid substitution, a mutation responsible for resistance in other species. Crosses between resistant lines and a susceptible line demonstrated that the inheritance of the mutation corresponded with the resistance phenotype in the F2. The resistance trait behaved as a single, fully dominant allele, which makes it easier to transfer it to carinata lines with desirable agronomic traits. The resistant lines developed here provide flexibility for use in multiple crop rotations and opens the possibility to use ALS‐inhibiting herbicides for weed control within this crop's growing season. Core Ideas: Brassica carinata is a new crop for biofuel production.Proper integration of this crop to existing rotations is critical.High sensitivity to herbicides used in other crops in the rotation is a major limitation for adoption.Acetolactate synthase (ALS)‐resistant B. carinata lines were developed to avoid injury and increase weed control options in this crop.ALS‐resistance will increase the number and type of crop rotations in which B. carinata can be included. Plain Language Summary: Brassica carinata A. Braun (carinata) is a new crop for biofuel production. Carinata is highly sensitive acetolactate synthase (ALS)‐inhibiting herbicide with long soil residual activity, and this has become a major limitation for growers' adoption. Having lines that are not affected by those herbicides will provide flexibility for rotating carinata with other crops. The objective of the study was to develop carinata lines resistant to ALS‐inhibiting herbicides. Screening carinata germplasm for reduced sensitivity to imazethapyr, an ALS‐inhibiting herbicide, allowed identifying five lines with high levels of resistance. The lines exhibited 4X–9X doses compared with susceptible lines. The resistance was confirmed under field conditions. Genetic analysis indicated that the resistance is controlled by a single, fully dominant allele, which makes it easier to transfer it to carinata lines with desirable agronomic traits. [ABSTRACT FROM AUTHOR]

Weed competition significantly impacts sesame yields, making herbicide use essential in both pre-and post-emergence stages. However, current agricultural practices do not endorse the application of post-emergence herbicides in sesame cultivation due to potential crop sensitivity issues. This study screened two susceptible varieties (VRI 2 and VRI 5), and three tolerant genotypes for imazethapyr herbicide tolerance and reduction indices of 14 quantitative traits. The tolerant lines, IC 0131493, IC 0204614, and IC 0205513 displayed excellent tolerance with an injury score of 1 at 1ml/L, 2ml/L, and 3ml/L on 90 days after sowing, whereas VRI 2 and VRI 5 were highly sensitive with a score of 4. The reduction indices of various quantitative traits showed significant reductions due to the application of imazethapyr herbicide in the susceptible lines than in the tolerant genotypes. Three cross combinations were made using these parents, viz., VRI 5 x IC 0131493, VRI 2 x IC 0204614, and VRI 5 x IC 0205513, and studied for the inheritance of Imazethapyr herbicide tolerance. The segregation patterns in the F1, F2, and BC1 populations revealed that a single dominant gene governs Imazethapyr herbicide tolerance. The present investigation provides a foundation for breeding imazethapyr herbicide-tolerant varieties in sesame. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at Agronomy Instructional Farm, Department of Agronomy, Chimanbhai Patel College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, Banaskantha (North Gujarat Agro-climatic Zone of Gujarat) during June-October, 2021 to assess the effect of pre- and post-emergence herbicides on weed control in groundnut crop using Randomized Block Design with ten treatments and four replications. Among different weed management practices, two hand weeding at 20 and 40 DAS recorded significantly higher number of pods per plant, resulted in significantly higher pod yield and haulm yield (23.70, 1980 kg ha-1 and 3082 kg ha-1, respectively) which was found at par with interculturing and hand weeding at 15 and 30 DAS (22.90, 1892 kg ha-1 and 2950 kg ha-1, respectively), post-emergence application of sodium acifluorfen 16.5+clodinafop-propargyl 8 EC @ 165+80 g ha-1 (22.53, 1835 kg ha-1 and 2864 kg ha-1, respectively) and imazethapyr 35 WG+imazamox 35 WG @ 70 g ha-1 (21.93, 1800 kg ha-1 and 2811 kg ha-1, respectively) due to better weed control of weeds as indicated by significantly lower density of sedges, grasses, broad leaf weeds and total weeds as evidenced by correlation and regression analysis between total weed density at 60 DAS, at harvest with the pod yield. Whereas, significantly lower number of pods per plant, pod yield and haulm yield at harvest were observed under unweeded check (10.30, 846 kg ha-1 and 1333 kg ha-1, respectively) due to significantly higher density of sedges, grasses, broad leaf weeds and total weeds observed in unweeded check. [ABSTRACT FROM AUTHOR]

Effective weed management is crucial for the successful cultivation of horsegram (Macrotyloma uniflorum), a drought-tolerant leguminous crop. This study evaluates the bio-efficacy of various herbicides on weed dynamics and the productivity of horsegram. Field experiments were conducted under AICRP on Arid legumes at ARS Ananthapuramu, where different herbicide treatments were compared with hand weeding and a weedy check during kharif 2023. The experiment comprised of eight post emergent treatments which include six herbicides treatments (quizalofop ethyl, haloxyfop-R-methyl, clodinafop propargyl, fenoxaprop-p-ethyl, propaquizafop, imazethapyr sprayed at 15-20 DAS), two hand weedings at 20 and 40 DAS and weedy check replicated thrice in Randomized Block Design. Major weeds were Rottboellia cochinchinensis among grasses, Fimbriocytis spp. among sedges, Celosia argentea, Murdania nudiflora and Digitaria sanguinalis among broadleaved weeds. Quizalofop ethyl and Propaquizafop effectively controlled Rottboellia cochinchinensis and Fimbriocytis spp. Imazethapyr effectively controlled broad leaved weeds. The results demonstrated that hand weeding twice recorded higher seed yield, haulm yield and net returns. Among herbicide treatments, quizalofop ethyl @ 50 g a.i./ha as PoE at 15 - 20 DAS recorded higher seed yield (807 kg/ha), haulm yield (1588 kg/ha) and net returns (15535 Rs/ha) and imazethapyr @ 40 g a.i./ha as PoE at 15 - 20 DAS recorded higher B:C ratio (2.84). [ABSTRACT FROM AUTHOR]

Industrial hemp (Cannabis sativa) production is complex, with strict regulatory constraints and challenges associated with a lack of labeled pesticides due to its status as a novel crop in the US. Four experiments were conducted in 2020 and 2021 to establish herbicide tolerances for hemp production in the coastal plain of Georgia, USA. Objectives included evaluating hemp response to pretransplant or posttransplant herbicides, determining if planting method influenced herbicide injury from residual preplant applied herbicides, and understanding how plastic mulch may influence hemp flower yields. When applied one day prior to transplanting, maximum hemp crop visual injury was less than 12% compared to the untreated control, with acetochlor, flumioxazin, fomesafen, pendimethalin, and norflurazon while dithiopyr, halosulfuron, isoxaben, and isoxaflutole resulted in greater than 50% injury. Posttransplant applications of S-metolachlor, acetochlor, pendimethalin, and clethodim resulted in less than 15% injury while halosulfuron, metribuzin, trifloxysulfuron, imazethapyr, and prometryn applications resulted in greater than 50% injury to plants. Preplant and posttransplant applied herbicides were found to have little effect on total tetrahydrocannabinol (THC), cannabidiol (CBD), or total cannabinoids in the dry flower after harvest. In a separate experiment, injury from halosulfuron and metribuzin was 52% to 56% less when planted with a mechanical transplanter as compared to the practice of using a transplant wheel to depress a hole in the soil followed by hand transplanting. In the final experiment, hemp dry flower yield in a non-plastic mulched (bareground) system was similar to that in a plastic mulched system. However, early season plant above-ground biomass was less in the plastic mulched system, which may have been due to elevated soil temperatures inhibiting early season growth. [ABSTRACT FROM AUTHOR]

Background: The Groundnut or Goober peas (Arachis hypogaea L.) hold a prominent position as one of India’s most crucial food and cash crops. One of the serious bottlenecks that limit the productivity of groundnut is the weed menace. Methods: A field experiment was conducted at Perunthalaivar Kamaraj Krishi Vigyan Kendra, Puducherry during 2021 to 2023 to investigate the effects of integrated weed management practices on groundnut cultivation. The experimental setup followed a randomized block design with nine treatments, each replicated three times. The treatments comprised a range of weed management practices, including the pre-emergence herbicide pendimethalin and post-emergence herbicides like imazethapyr and quizalofop-ethyl. These herbicides were administered either individually or in conjunction with hand weeding once. In addition, hand weedings twice at 20 and 40 DAS were tested with unweeded check. Result: The experiment results of the two years study revealed that the application of Pendimethalin 30% EC + Imazethapyr 2% EC with quizalofop - p- ethyl at 15-20 DAS has gave the maximum plant height (74.7 cm), dry matter production (57.9 g /plant), higher pod yield (3922 kg/ha), haulm yield (5919 kg/ha), highest net return (Rs. 91763 ha -1) and B: C ratio (2.75). The strong positive correlations are plant height (0.96 and 0.97), shelling % (0.98 and 0.99), no. of pods plant-1 (0.98 and 0.99), dry matter production (0.98 and 0.99) and weed control efficiency (0.85 and 0.88). These variables had a positive impact on groundnut yield. [ABSTRACT FROM AUTHOR]

Field dodder (Cuscuta campestris yuncker) is an important parasitic weed that has negative impacts on the growth and yield of alfalfa (Medicago sativa L.). Effective control of field dodder in alfalfa crops is necessary to reduce yield losses. Field studies were conducted to evaluate the efficacy of various herbicides on field dodder in a new-seeded alfalfa crop at three locations (Karaj, Jiroft, and Urmia) in Iran during 2020–2021. The herbicides evaluated were imazethapyr (100 g a.i. ha−1), glyphosate (six doses ranging from 143 to 348 g a.i. ha−1 + ammonium sulfate at 8 kg ha−1), and propyzamide (1250, 1500, and 1750 g a.i. ha−1). The results demonstrated that propyzamide at 1750 g a.i. ha−1 provided complete control of field dodder in terms of percentage change in biomass at first (100%) and second (99%) cuttings of alfalfa in Urmia. The imazethapyr at 100 g a.i. ha−1 provided 96 and 87% control at the first and second cuttings, respectively, whereas propyzamide at 1750 g a.i. ha−1 showed the best efficacy in increasing alfalfa biomass at the first (up to 82%) and the second cuttings (up to 81%), depending on the location. Glyphosate provided reasonable control of the field dodder at the first (73%) and the second cutting (82%). However, at higher rates (307 and 348 g a.i. ha−1), it caused significant reductions in alfalfa biomass due to crop injury, especially at the first cutting. The use of propyzamide at 1750 g a.i. ha−1 is recommended for highly effective control of field dodder in alfalfa crops without compromising the crop yield. [ABSTRACT FROM AUTHOR]

AbstractThis study aimed to assess the efficacy of commonly used post-emergence herbicides under flooded rice fields, for Conyza spp. control. The greenhouse experiment employed a factorial setup with factor A denoting the presence or absence of a water layer post-application, and factor B representing different herbicides, to C. sumatrensis. In field trials, were applied when the rice plantation was on V3 stage. Evaluations were control (%), roots and shoot dry weight of Conyza spp., as well as injury (%), number of grains per panicle, and grain yield (ha−1) of rice. The applications of imazapyr + imazapic, florpyrauxifen-benzyl, imazethapyr, penoxsulam, quinclorac, bentazon, triclopyr-butyl, saflufenacil and ethoxysulfuron followed by water layer entry led to Conyza spp. control surpassing 80% at 28 DAA. The herbicides florpyrauxifen-benzyl, quinclorac, triclopyr-butyl, and saflufenacil, without flooding after application, demonstrated Sumatran fleabane control equal to or greater than 80% at 28 DAA. Effective water layer management is crucial for Conyza spp. control in zero-grade rice cultivation areas. [ABSTRACT FROM AUTHOR]

In order to improve both resistance to lepidopteran pests and resistance to the herbicide imazethapyr in mainstay japonica varieties of the Huang-Huai rice region, Sanming dominant genic male sterile (S-DGMS) rice was used as a platform to facilitate the pyramiding of functional genes and the replacement of the genomic background. Twelve novel lines were developed, each carrying a crystal toxin gene conferring resistance to lepidopteran pests and the ALS627N allele conferring resistance to herbicide imazethapyr in the background of a mainstay japonica variety. The genomic background of the 12 novel lines was examined using 48 specified molecular markers, and each line carried less than two polymorphic markers relative to the corresponding mainstay variety. All 12 lines displayed high resistance to lepidopteran pests and the herbicide imazethapyr. The major agronomic traits of the 12 lines showed no difference relative to the responding mainstay variety when sprayed with pesticide. The popularization of the 12 japonica lines could reduce the use of pesticides and provide highly efficient control of weeds and weedy rice in the future, thus promoting the development of japonica rice production. Therefore, S-DGMS rice could be a powerful tool for the genetic improvement of target traits in rice.

The management of invasive weeds on both arable and non-arable land is a vast challenge. Converting these invasive weeds into biochar and using them to control the fate of herbicides in soil could be an effective strategy within the concept of turning waste into a wealth product. In this study, the fate of imazethapyr (IMZ), a commonly used herbicide in various crops, was investigated by introducing such weeds as biochar, i.e., Parthenium hysterophorus (PB) and Lantana camara (LB) in sandy loam soil. In terms of kinetics, the pseudo-second order (PSO) model provided the best fit for both biochar-mixed soils. More IMZ was sorbed onto LB-mixed soil compared to PB-mixed soil. When compared to the control (no biochar), both PB and LB biochars (at concentrations of 0.2% and 0.5%) increased IMZ adsorption, although the extent of this effect varied depending on the dosage and type of biochar. The Freundlich adsorption isotherm provided a satisfactory explanation for IMZ adsorption in soil/soil mixed with biochar, with the adsorption process exhibiting high nonlinearity. The values of Gibb's free energy change (ΔG) were negative for both adsorption and desorption in soil/soil mixed with biochar, indicating that sorption was exothermic and spontaneous. Both types of biochar significantly affect IMZ dissipation, with higher degradation observed in LB-amended soil compared to PB-amended soil. Hence, the findings suggest that the preparation of biochar from invasive weeds and its utilization for managing the fate of herbicides can effectively reduce the residual toxicity of IMZ in treated agroecosystems in tropical and subtropical regions. [ABSTRACT FROM AUTHOR]

Weedy rice is the most challenging weed species to remove in rice production. We found a novel phenotype of seedling leaves which rapidly generates necrotic spots in response to imidazolinone herbicides in weedy rice, but its influencing factors and formation basis are still unknown. In this study, we used the leaf necrotic spot-producing type of weedy rice as the material. First, leaf necrotic spots were defined as physiological and vacuole-mediated cell necrosis by microscopic examination. The imazethapyr concentration was positively correlated with the degree of necrotic spots occurring, while the action site was in accordance with necrosis using herbicide stability tests combined with fluorescence parameters. Furthermore, transcriptome analysis revealed significant differences in the gene expression of endoplasmic reticulum stress and the lipid metabolism membrane structure damage pathway during necrosis, as confirmed by transmission electron microscopy. The light–temperature test also showed that high temperature and intense light could promote the appearance of necrotic spots. These experimental results are helpful in clarifying the process and basis of imazethapyr in inducing the rapid generation of necrotic spots in rice leaves and providing new insight into understanding the mechanism of response to imidazolinone herbicides and the control of weedy rice. [ABSTRACT FROM AUTHOR]

IntroductionWeeds are one of the most problematic factors in chickpea production systems and chemical control of weeds is limited in Iran because of registered selective herbicides for this crop are not available for farmers. In this situation, optimizing of herbicide application (especially soil-applied herbicides) is one way that can help farmers to combat with weeds. Incorporated By Sowing (IBS) is one of the best way for optimizing of non-selective soil herbicides application in crops. The purpose of this experiment is to investigate the possibility application of non-selective soil-applied herbicides in directed planting of chickpea via IBS. Material and MethodsApplication possibility of non-selective herbicides in directed sowing of chickpea was evaluated in Ardabil and Zanjan in 2020. The treatments were arranged in a strip plot experiment with randomized complete block design and 3 replications. The vertical factor was herbicide application (including: trifluralin, metribuzin, pendimethalin, imazethapyr, and their combination with (phenmedipham+desmedipham+ethofumesate), and also oxyfluorfen and weedy and weed free controls. Horizontal factor was incorporated by sowing (IBS) methods (including: incorporate by seed planter and cultivator+seed planter). Seed germination of chickpea, weed density and biomass and chickpea grain yield were evaluated 30 days after herbicide application and in the end of chickpea growth. Results and DiscussionIBS methods did not have a significant impact on weed and chickpea density and biomass. Therefore, the use of a cultivator before seed planting is only recommended when the seedbed is inadequately prepared or if pre-planting weed control has not been effectively executed. In contrast, herbicides had significant effects on weeds population and chickpea in experimental locations. In Ardabil, pendimetalin and pendimetalin + (phenmedipham + desmedipham + ethofumesate) were the only treatments that had low efficacy on weeds (with 48.9 and 51.7 % weed biomass reduction respectively) and other treatments had no significant difference in 30 days after herbicides application. In the end of growing season, the highest weeds biomass reduction (in compared with control) were recorded in trifluralin, metribuzin and imazethapyr in combination with (phenmedipham + desmedipham + ethofumesate) and oxyfluorfen (with 84, 83, 80 and 70 of control (%) respectively). In Zanjan, single application of trifluralin and metribuzin and their combination with (phenmedipham + desmedipham + ethofumesate) and combination of imazethapyr with (phenmedipham + desmedipham + ethofumesate) had the highest weed control with 79, 71, 78.6 and 75.5 % respectively. In contrast with Ardabil, the lowest weed control efficacy was recorded in oxyfluorfen plots (22.4%). Grain yield of chickpea was also high in trifluralin + (phenmedipham + desmedipham + ethofumesate) and was low in imazethapyr in Zanjan and Ardabil. ConclusionsApplication of soil herbicides (including: Metribuzin and Trifluralin) in chickpea is possible only if, farmers use them just before sowing and incorporate the herbicides into the seedbed during the sowing process.

Imazethapyr is a widely used imidazolinone herbicide worldwide, and its potential adverse effects on non-target plants have raised concerns. Understanding the mechanisms of imazethapyr phytotoxicity is crucial for its agro-ecological risk assessment. Here, the comprehensive molecular responses and metabolic alterations of Arabidopsis in response to imazethapyr were investigated. Our results showed that root exposure to imazethapyr inhibited shoot growth, reduced chlorophyll contents, induced photoinhibition and decreased photosynthetic activity. By non-target metabolomic analysis, we identified 75 metabolites that were significantly changed after imazethapyr exposure, and they are mainly enriched in carbohydrate, lipid and amino acid metabolism. Transcriptomic analysis confirmed that imazethapyr significantly downregulated the genes involved in photosynthetic electron transport and the carbon cycle. In detail, 48 genes in the photosynthetic lightreaction and 11 genes in Calvin cycle were downregulated. Additionally, the downregulation of genes related to electron transport in mitochondria provides strong evidence for imazethapyr inhibiting photosynthetic carbon fixation and cellular energy metabolism as one of mechanisms of toxicity. These results revealed the molecular and metabolic basis of imazethapyr toxicity on non-target plants, contributing to environmental risk assessment and mitigate negative impact of imazethapyr residues in agricultural soils. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during kharif 2021 to assess the effect of various weed management practices in groundnut at Agronomy Instructional Farm, Chimanbhai Patel College of Agriculture, Sardarkrushinagar, Dantiwada Agricultural University, Sardarkrushinagar on loamy sand soil. Among different treatments, two hand weeding at 20 and 40 days after sowing (DAS) recorded significantly higher pod and haulm yield (1980 and 3082 kg/ha, respectively) and found at par with interculturing and hand weeding at 15 and 30 DAS (1892 and 2950 kg/ha, respectively), post-emergence application of sodium acifluorfen 16.5 + clodinafop-propargyl 8 EC @ 165+80 g/ha (1835 and 2864 kg/ha, respectively) and imazethapyr 35 WG + imazamox 35 WG @ 70 g/ha (1800 and 2811 kg/ha, respectively) as compared to unweeded check (846 and 1333 kg/ha, respectively) due to effective suppression of grasses, sedges, broad leaf and total weeds at 60 DAS and at harvest with higher weed control efficiency and lower weed index values. [ABSTRACT FROM AUTHOR]

Cluster bean (Cyamopsis tetragonoloba L.) is grown under both rainfed and irrigated conditions in Haryana and weeds pose serious threat to its production under both the conditions. Owing to increasing labour cost, there is need for chemical weed management, but, there is no chemical recommendation for weed management in cluster bean in Haryana. So, a field experiment was conducted during kharif season of 2018 and 2019 at Research Farm, Department of Agronomy, CCS Haryana Agricultural University, Hisar, India in a semi-arid climate. The experiment was laid out in split-plot design having three replications, with three irrigation levels viz., no post-sown irrigation, one irrigation and two irrigations in main plots, while five weed management practices viz., pendimethalin 1.0 kg/ha as PRE, imazethapyr 70 g/ha as PRE, imazethapyr 70 g/ha at 21 DAS, imazethapyr + imazamox (RM) 70 g/ha at 21 DAS and farmers' practice (2 hand weedings at 3 and 5 WAS) in sub-plots. The cluster bean crop was infested with Cyperus rotundus, Convolvulus arvensis, Digera arvensis and Echinochloa colona. The dry weight of weeds at 60 DAS and at harvest increased with the increasing irrigation levels. Among the weed management practices, two hand weedings at 3 and 5 WAS, produced minimum weed dry weight at 30 DAS, 60 DAS and harvest, while, imazethapyr + imazamox (RM) 70 g/ha at 21 DAS was found most effective in controlling the weeds among the chemical methods. During both the years, maximum seed yield of cluster bean was produced by irrigating the crop with two irrigations (1036 and 726 kg/ha), which was statistically at par with one irrigation (1009 and 682 kg/ha, during 2018 and 2019, respectively). Two hand weedings at 3 and 5 WAS, was found superior to chemical weed control treatments in producing seed yield (1121 and 754 kg/ha during 2018 and 2019, respectively). However, imazethapyr + imazamox (RM) 70 g/ha at 21 DAS produced highest seed yield (968 and 674 kg/ha, during 2018 and 2019, respectively), which was statistically similar to imazethapyr 70 g/ha PRE (932 and 654 kg/ha, during 2018 and 2019, respectively) and both of them were superior to imazethapyr 70 g/ha at 21 DAS and pendimethalin 1.0 kg/ha as PRE. The bacterial and PSB count at harvest of cluster bean crop increased with increase in irrigation levels and bacterial population was lower with soil application of herbicides (either pendimethalin or imazethapyr) as compared to foliar application of herbicides and 2 HW treatments, however, PSB population was not affected by weed management practices. Maximum herbicide residue at harvest of the cluster bean crop was found in imazethapyr 70 g/ha at 21 DAS and followed by imazethapyr 70 g/ha PRE and imazethapyr + imazamox (RM) 70 g/ha at 20 DAS. Reduction in the germination, growth and yield of mustard was observed due to residual effect of the chemicals applied in cluster bean during both years of study, maximum being with imazethapyr 70 g/ha at 21 DAS followed by imazethapyr 70 g/ha PRE and imazethapyr + imazamox (RM) 70 g/ha at 21 DAS. [ABSTRACT FROM AUTHOR]