Dry direct-seeded rice, Economics, Grain yield, Weed management, Weed flora.

The shift in the method of rice establishment from traditional manual transplanting of seedlings to direct seeding has occurred in many Asian countries including India. Weeds are the most important biotic constraint in dry direct-seeded rice (dry-DSR) production. Field experiments were carried out during 2015-16 and 2016-17 at Pandit Jawaharlal Nehru College of Agriculture & Research Institute, Karaikal, and Puducherry UT, India to study the effect of different weed management options on the diverse weed flora, rice grain yield and economics in dry-DSR under unpuddled condition. The grassy weeds dominated the weed flora, with 86.12% relative density of Echinochloa colona (L). Link. The sequential application of pendimethalin and bispyribac-sodium herbicides (1000 fb 25 g/ha) with a manual weeding in 40 days after sowing (DAS) reduced total weed density (14.4 /m2) and biomass (37 g/m2), resulted in better rice growth (plant height and tillers/m2), yield parameters (panicle weight and 1000 grain weight) and higher rice grain yield (3.86 t/ha). Negative linear relationship was observed between rice grain yield and total weed biomass at 80 DAS. Uncontrolled weeds caused 68.3% dry-DSR yield loss. Pre-emergence pendimethalin 1.0 kg/ha application integrated with manual weeding with or without bispyribac-sodium application and manual weeding thrice recorded higher B: C ratio in deltaic coastal ecosystem of Karaikal, Puducherry UT.

Cropping system, Long-term effect, Rice-chickpea, Tillage, Weed management, Weed seed bank, Weed shift

A long-term experiment was conducted on Inceptisol at Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh during 2010 to 2015 in direct-seeded rice (DSR)-chickpea cropping system to study the effect of continuous and rotational use of weed management practices on weed shift and productivity. No remarkable weed shift was visualized due to continuous or rotational application of combination of herbicides or manual weeding or its integration. However, appearance of Celosia argentea in unweeded plot was noticed in sixth year of DSR mainly due to its aggressive growth habit and non-submergence of rice field during Kharif 2015. The appearance of Celosia argentea suppressed the Alternanthera triandra. The Celosia argentea produced 8430 seeds/plant as against 1564 seeds/plant by Alternanthera triandra. Significantly higher seed yield of rice was registered under two hand weedings followed by oxadiargyl 80 g/ha fb bispyribac 25 g/ha. Seed yield of chickpea was higher under conventional tillage and continuous application of pendimethalin 1000 g/ha. Studies on weed seed bank suggested that although, there was no effect of different weed management treatments on seed bank up to 15 cm soil depth neither in DSR nor in chickpea at initial stage, but in unweeded control plot, there was perceptible variation in number of weed seeds of different annual weed species. The dominant weeds species were Celosia argentea (37.7%), Echinochloa colona (19.6%), Ischaemum rugosum (14.7%) and Cyperus iria (9.8%) over initially dominant species of Alternanthera triandra.

Herbicide, Microbial population, Weed, Wheat, Yield

A field experiment was conducted at District Seed Farm (AB Block), Kalyani under Bidhan Chandra Krishi Vishwavidyalaya during winter season of 2016-17 and 2017-18 in upland situation to evaluate the effect of various herbicides and it’s combinations against different weed species and yield of wheat under new alluvial zone. The experiment was carried out in a randomized block design with eleven treatments in three replications. Total weed density at 30 days after spray, was recorded minimum with halauxifen-methyl-ester + florasulam + carfentrazone 10.21 + 20 g/ha and it was at par with the metsulfuron + carfentrazone 4 + 20 g/ha and considerably better than all other control measures except weed free situation. At 30 days after spray, least total weed biomass was observed with the 2,4-D E + carfentrazone 400 + 20 g/ha and showed parity with the halauxifen + florasulam + carfentrazone 10.21 + 20 g/ha, metsulfuron + carfentrazone 4 + 20        g/ha and halauxifen-methyl ester + florasulam 12.76 g/ha and statistically better than all other treatments except weed free situation. Amongst various herbicidal treatments, total weed density at 60 days after spray, lowest with halauxifen-methyl-ester + florasulam 12.76 g/ha and was at par with most of the treatments except 2,4-D Na 500 g/ha, 2,4-D Na + carfentrazone 400 + 20 g/ha and weedy check. This treatment also registered low weed biomass. The soil microbial population was significantly affected by weed control measures at 60 days after sowing.Higher grain yield of wheat was observed in weed free (4.80 t/ha) and was at par with metsulfuron + carfentrazone 4 + 20 g/ha (4.56 t/ha), halauxifen-methyl ester + florasulam + carfentrazone 10.21 + 20 g/ha (4.44 t/ha) and 2,4-D E + carfentrazone 400 + 20 g/ha (4.40 t/ha) and significantly better than other treatments. Total nutrient uptake by crop was highest in weed free and was at par with metsulfuron + carfentrazone 4 + 20 g/ha and significantly better to other treatments. From the study. It was concluded that use of metsulfuron + carfentrazone 4 + 20 g/ha resulted in maximum wheat yield followed by halauxifen-methyl ester + florasulam + carfentrazone 10.21 + 20 g/ha.

Absolute density, Cattle shed water, Endozoochory, Weed

The effectiveness of endozoochory and germination success of the weeds after passage through the animal gut are the important traits for dissemination and invasion of weeds. With this view, experiments were conducted during the Rabi season of 2017-18 and 2018-19 at ICAR-Indian Veterinary Research Institute (IVRI), Izatnagar Campus with the objective to assess the effect of endozoochorous dissemination of weed (Rumex dentatus) on late sown wheat productivity (Variety HD 3059) while using cattle shed water for irrigation. The results revealed that late harvesting of the berseem led to the development of   R. dentatus up to seeding stage. Berseem green fodder contaminated with seeds of R. dentatus was fed to the cattle and buffaloes. Application of carfentrazone at 25 days after sowing (DAS) reduced the population of existing broad-leaved weeds, however, use of cattle shed water for irrigation increased the population of R. dentatus from 35 DAS up to 17% at 50 DAS, 134% at 65 DAS and 186% at 80 DAS. Whereas, the adjacent plot irrigated with normal ground water, recorded the declining trend of R. dentatus population from 35 DAS i.e. up to 15, 32 and 50% reduction at 50, 65 and 80 DAS, respectively. Large infestation of R. dentatus due to use of cattle shed water contaminated with seeds of R. dentatus reduced wheat productivity up to 44% (2.14 t/ha) as compared to the grain yield 3.82 t/ha obtained from the plot irrigated with normal ground water. During second year, the entire field was irrigated with normal ground water and similarly carfentrazone was used at 25 DAS. These measures reduced the population of R. dentatus and weed showed declining trend up to 30, 71 and 79% reduction at 50, 65 and 80 DAS from 35 DAS. These results confirmed that R. dentatus has the endozoochorous mechanism of its dissemination and use of cattle shed water for irrigation may not be recommended if the berseem fodder is infested with seeds of R. dentatus.

Economics, Stale seed bed, Tillage, Wheat, Weed control, Yield

A field experiment was carried out at SKRAU, Bikaner, Rajasthan, during Rabi seasons of 2016-17 and 2017-18 to investigate the effect of tillage and weed management practices on productivity of wheat (Triticum aestivum) in North- West Rajasthan. Amongst the tillage treatments, adoption of stale seedbed (SSB) using glyphosate at 2.0 kg/ha resulted in higher dry matter at harvest, effective tillers (101.77 per m.r.l.) and grain yield (4.06 t/ha), and significantly lowered the density and dry matter of weeds. Among various weed management treatments, metsulfuron 4.0 g/ha + one hand weeding (HW) at 45 DAS significantly lowered the density and dry matter of all the broad-leaf weeds, but not effective against Cyperus rotundus and Cynodon dactylon. Being at par with weed free check and also 2,4-D E + one HW, it was significantly superior to all other treatments and resulted 4.40 t/ha grain yield of wheat.

Brown manuring, Clodinafop + MSM, Sesbania, Weeds, Wheat, Zero-till

A 3-year study was conducted to assess the impact of tillage and weed control practices on weed flora and wheat productivity. Experiments were conducted during Rabi season of 2012-13 to 2014-15 at GBPUA&T, Pantnagar, with clay-loam soil. There were five crop establishment methods, viz. Transplanted rice (conventional tillage) (TPR)– wheat (conventional tillage) (CTW) (TPR-CTW), Transplanted rice (conventional tillage)– wheat (zero tillage)- Sesbania green manuring (S) (TPR-ZTW-S),  Direct-seeded rice (conventional tillage)- wheat (conventional tillage)- Sesbania incorporation (S) (DSR-CTW-S), Direct-seeded rice (zero tillage)- wheat (zero tillage)- Sesbania brown manuring (S) (ZTR-ZTW-S) and Direct-seeded rice (zero tillage) + residue retention- wheat (zero tillage) + residue retention- Sesbania brown manuring (S) (ZTR + R-ZTW+R-ZTS) and three weed control methods [(weedy check, recommended herbicide (Recommended ready-mix herbicide clodinafop 15% + MSM 1% (60 + 4 g/ha) and integrated weed management i.e., clodinafop 15% + MSM 1% 60 + 4 g/ha fb manual weeding at 45 days after seeding (DAS)]. Continuous zero-till cropping system along with residue retention and brown manuring of Sesbania has resulted in the lowest total weed biomass at 60 DAS and greatly reduced the density of Phalaris minor, Medicago denticulata, Polygonum plebeium and Coronopus didymus. However, density of C. didymus, Rumex acetosella and Vicia sativa was reduced under conventionally tilled wheat. Ready mix application of clodinafop 15% + MSM 1% supplemented with one hand weeding at 45 DAS greatly reduced the density and biomass of weeds. The maximum wheat grain (4.5 t/ha) and straw (6.3 t/ha) yields was achieved under zero-tilled wheat with rice residue retention and Sesbania as brown manure. The integration of clodinafop 15% + MSM 1% with 1 HW at 45 DAS resulted in an increase in grain and straw yields by 45.5% and 30.8%, respectively, over weedy check. It may inferred that in wheat cultivation conventional tillage could be replaced with zero-tillage along with residue retention by growing of Sesbania and the application of 2,4-D at 30 days stage to attain sustainability of rice-wheat cropping system.

Barley, Economics, Grain yield, Herbicides, Weeds

A field experiment was conducted during 2014-15 and 2015-16 to study the efficacy of herbicides for control of diverse weeds in barley. Herbicides were sprayed alone or in combinations. The highest grain yield (5.54-6.07 t/ha) was recorded in weed-free treatment which was at par with isoproturon 750 g/ha + 2,4-D 500 g/ha and pinoxaden 40 g/ha + carfentrazone 20 g/ha. Uncontrolled weed competition caused an average 8-54% yield reductions compared to weed-free treatment. The magnitude of net returns and the benefit-cost ratio was higher with the applications of isoproturon 750 g/ha + 2,4-D (Na salt) 500 g/ha, pinoxaden 40 g/ha + carfentrazone 20 g/ha, isoproturon 750 g/ha + metsulfuron 4 g/ha and pinoxaden 40 g/ha followed by metsulfuron 4 g/ha and in weed-free.

Atrazine, Economics, Maize, Tembotrione, WCE

A field investigation was carried out at Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola during three consecutive Kharif seasons (2016-2018) to study the relative efficacy of herbicides on weed control in maize. Results revealed that, among the herbicidal treatments, atrazine 0.5 kg/ha fb tembotrione 0.120 kg/ha PoE at 20 DAS produced less weed count and weed dry matter than rest of the herbicides. Among the herbicidal treatments, maximum growth and yield attributes were recorded with treatment of atrazine 0.5 kg/ha fb tembotrione 0.120 kg/ha which was at par with atrazine 0.5 kg/ha fb 2,4-D sodium salt 0.5 kg/ha. Yield reduction varied from 12.49% to 54.17% in the herbicide applied plots as compared to weed free treatment. Atrazine 0.5 kg/ha fb tembotrione 0.120 kg/ha PoE 20 DAS (4.33 t/ha) and atrazine 1.0 kg/ha PE (3.89 t/ha) proved as effective as weed free treatment (4.91 t/ha) and recorded significantly higher grain yield with net monitory returns of  47832/ha and B:C ratio of 3.22.

Blackgram, Pendimethalin + imazethapyr, Hand weeding, WCE

A field experiment on effect of different weed management practices in blackgram under acidic soils of Manipur was conducted at C.A.U. research farm, Andro, Imphal East of Central Agricultural University, Manipur during Kharif season 2013, 2014 and 2015. It was laid out in randomized block design with nine different weed management treatments, viz. pre-emergence application of pendimethalin 1.0 kg/ha, pendimethalin + imazethapyr 1.0 kg/ha, pendimethalin 1.0 kg/ha + quizalofop-ethyl 75 g as post-emergence application, pendimethalin + imazethapyr 1.0 kg/ha + quizalofop-ethyl 75 g as post-emergence application, pendimethalin 1.0 kg/ha + imazethapyr 55 g/ha, pendimethalin 1.0 kg/ha + hand weeding at 30 DAS, pendimethalin + imazethapyr 1.0 kg/ha + hand weeding at 30 DAS and twice hand weeding at 20 and 40 DAS. Pendimethalin1.0 kg/ha with hand weeding twice at 20 and 40 DAS recorded significant reduction in weed density, weed biomass and weed control efficiency followed by pre-emergence application of pendimethalin + imazethapyr 1.0 kg/ha, + hand weeding at 25 DAS. Significantly higher number of pods per plant, seed and stover yield and growth attributes like plant height and number of branches per plant were recorded under twice hand weeding followed by integrated treatment of pendimethalin + imazethapyr 1.0 kg/ha + hand weeding.

Allelopathy, Sunflower, Intercropping, Weed management, Productivity

Field experiments were conducted during summer 2016 and winter 2016-17 at Agricultural College and Research Institute, Madurai to study the allelopathic effect of different intercrops and tree leaf extracts in managing weeds and increasing productivity of cotton. The cotton + sorghum intercropping system registered lower weed density at 20, 40 and at 60 days after seeding (DAS) during both the seasons. Among the weed management practices, lower weed density was recorded with pre-emergence application of pendimethalin at 1.0 kg/ha at 20 DAS and with hand weeding twice at 20 and 40 DAS at 40 and 60 DAS during studied periods. The highest cotton equivalent yield (389, 419       kg/ha), land equivalent ratio (1.52, 1.54), monetary equivalent ratio (1.18, 1.17) and system productivity (2.13, 2.39 t/ha) were recorded in cotton + sunflower intercropping system with hand weeding twice at 20 and 40 DAS during both the years. Among the combined applications of intercropping system and tree leaf extracts, cotton + sunflower (1:1) + pre-emergence application of Mangifera indica leaf extract at 30% + hand weeding at 40 DAS registered the maximum cotton equivalent yield (349, 374 kg/ha), land equivalent ratio (1.31, 1.34), monetary equivalent ratio (1.0, 1.02) and system productivity (1.81, 2.07 t/ha) during summer 2016 and winter 2016-17, respectively.

Bio-efficacy, Glufosinate ammonium, Quality assessment, Soil microbes, Tea, Weed management

Field trials were conducted in Tarai region of Jalpaiguri, West Bengal, India (26°88 N latitude; 88°32 E longitude, and 122 m above mean sea level) under natural weed infestations in tea garden during 2017 and 2018 to evaluate the efficacy of herbicides on weed flora, non-target soil organisms, leaf quality and productivity of tea (var. TV-23). The pattern of nutrient uptake and soil physico-chemicals properties were also itemized. The treatments were comprised of three doses of glufosinate ammonium 13.5% SL (0.27, 0.34, 0.45 kg/ha), glyphosate 41% SL (1.23 kg/ha), paraquat dichloride 24% SL (0.60 kg/ha) and weedy check within a randomized complete block design, replicated four times. The results revealed that glufosinate ammonium at 0.45 kg/ha was the most efficient against grassy and broad-leaf weeds with higher weed control efficiency (> 90%) and total green leaf yield (3.0 t/ha and 2.96 t/ha). Herbicides did not show any phytotoxicity symptoms on the matured tea plants throughout the observation period. An initial detrimental effect on rhizospheric micro-flora (total bacteria, fungi, and actinomycetes) was imposed by residual toxicity of herbicides but at later stage, no harmful effects were observed. Maximum nutrients uptake and soil available nutrients were determined under the higher dose of glufosinate ammonium. Tea leaf quality did not significantly influence by weed management practices. Based on overall performance, the glufosinate ammonium 0.45 kg/ha may be considered as the best substitute for others post-emergent herbicide against the complex weed floras in tea garden.

Brown manuring, Direct-seeded rice, Overall impact index, Sequential applications, Weed control index

Weeds are the major biotic stress limiting productivity, profitability and sustainability of direct-seeded rice (DSR). Effective weed control determines the success of DSR. Therefore, a field study was undertaken to assess the impacts of potential pre- and post-emergence herbicides in sequence and integrated use of herbicides with other methods on weeds and DSR. Eleven weed control treatments comprising of six combinations of pre- and post-emergence herbicides, two brown manuring, one herbicide with manual weeding, and two control (weed-free check and unweeded control) were evaluated in a randomized complete block design with three replications. Results showed that grassy weeds were most dominant, constituting 66.0–91.8% of total weed dry weight across the treatments. Unit increase in weed density (per m2) and weed dry weight (g/m2) could reduce rice grain yield by 14.5 and 11 kg/ha, respectively. All weed control treatments impacted weed interference, crop growth and yield significantly. Sequential applications of pendimethalin (1.0 kg/ha) as pre-emergence and ready-mixture of penoxsulam + cyhalofop-butyl (130 g/ha) at 25 days after sowing (DAS) significantly reduced weed dry weight by 87.6% at harvest, and was superior to other treatments. This treatment increased rice grain yield (3.92 t/ha) by 378.9% over unweeded control, gross benefit: cost (2.30) by 31.4% over weed-free check, and gave highest overall impact index (1.27) with an economic threshold level of 9.0 weeds/m2, and found to be the best weed control option in DSR. Likewise, brown manuring followed by application of metsulfuron-methyl 10% + chlorimuron-ethyl 10% (20 g/ha Almix) at 40 DAS led to 80.3% reduction in weed dry weight, causing significant improvements in crop growth and grain yield (3.67 t/ha) with 30.3% higher gross benefit: cost over weed-free check, and could become a profitable alternative weed control option in DSR.

Bed, Planting density, Puddle, Ridge, Unpuddle

The effect of establishment methods and seedling density on weed dynamics, pest incidence and productivity of transplanted rice were evaluated in a field study, conducted in summer 2019 at Ludhiana, India.Three rice establishment methods [rice transplanted on puddled flat soil (PFTR), rice transplanted on unpuddled raised bed (UBTR), rice transplanted on unpuddled ridge (URTR)] in main plots, and three planting densities (20, 25, 33 seedling hills/m2) in sub-plots were evaluated in a split-plot design. It was found that UBTR and URTR methods had higher weed biomass than PFTR at 20 and 70 days after transplanting (DAT). All three establishment methods gave similar rice grain yield. Increase in planting density from 20 to 33 seedling hills/m2 reduced weed biomass at 20 and 70 DAT but at 45 DAT, all the planting densities had similar weed biomass. Likewise, there was consistent decline in rice grain yield due to reduction in planting densities but differences among consecutive planting densities were not significant. The incidence of insect-pest remained below economic threshold level under all treatments.

Grain yield, Growth parameters, Residual greengram, Seedling vigour index, Weed growth

A field experiment was conducted at Sri Venkateswara Agricultural College, Tirupati campus of Acharya N.G. Ranga Agricultural University, Andhra Pradesh, India to study the performance of sequential application of pre-emergence (PE) and post-emergence (PoE) herbicides for broad-spectrum weed control in rainfed lowland rice and their residual effect on succeeding greengram. The major weed flora associated with rainfed lowland rice were Cyperus rotundus L. (55%), Digitaria sanguinalis L. Scop (12%) and Commelina benghalensis L.(7%) and other weeds (26%). The lowest density and dry weight and increased growth and yield components were recorded with PE application of pendimethalin 1000 g/ha fb florpyrauxifen-benzyl 25 g/ha or halosulfuron-methyl 67.5 g/ha. The higher grain and straw yields and benefit-cost ratio were obtained with PE application of pendimethalin 1000 g/ha fb florpyrauxifen-benzyl 25 g/ha or halosulfuron-methyl 67.5 g/ha. Pre-emergence application of pretilachlor, oxadiargyl and pendimethalin reduced the plant population of rice by 12.10, 5.94 and 4.46%, respectively compared to unweeded check. Sequential application of PE and PoE herbicides applied to rainfed lowland rice did not affect the germination of greengram, however the best weed management practice in rice continuing its superiority in obtaining higher seedling vigour index and dry matter production at 15 DAS.

Direct-seeded rice, Herbicides, Live mulch, Nutrient uptake, Sesbania

A field experiment was conducted at Mata Gujri College, Fatehgarh Sahib, Punjab during rainy season of 2017 to study the effect of live mulches and herbicides in direct-seeded rice under irrigated condition. The experiment was laid out in a split-plot design with three replications. The live mulch include Sesbania rostrata, Vigna unguiculata and Sesamum indicum while weed management treatments were pendimethalin 1.0 kg/ha (PE) fb bispyribac-Na 25 g/ha (PoE), bispyribac-Na 25 g/ha + carfentrazone 20 g/ha (PoE), bispyribac-Na 25 g/ha + ethoxysulfuron 18 g/ha (PoE) and pendimethalin 1.0 kg/ha (PE) along with weed free and weedy checks. Results indicated that higher yield attributes and yield were recorded under live mulch with Sesbania rostrata, which was statistically at par with live mulch with Vigna unguiculata and significantly superior over live mulch with Sesamum indicum. Among herbicides, application of bispyribac-Na 25 g/ha + carfentrazone 20 g/ha being at par with bispyribac- Na 25 g/ha + ethoxysulfuron 18 g/ha was significantly superior over other treatments.

Herbicides, Weeds, Weed control efficiency, Wheat, Yield

A field experiment was conducted at Agronomic Research Station of Doon (P.G) College of Agriculture Science and Technology, Rampur (Selaqui) Dehradun, Uttarakhand during 2018-19 to study the effect of different herbicides in wheat. The experimental soil was sandy loam in texture, slightly acidic in nature with low in N, high in available P and medium in K. The results revealed that post-emergence application of sulfosulfuron 25 g/ha, followed by metsulfuron-methyl 4.0 g/ha gave the highest yield of wheat which was at par with manual weeding at 30, 60 and 90 DAS. Based on the results, hand weeding at 30, 60 and 90 days after sowing in wheat recorded the lowest values of weed count and biomass with the highest weed control efficiency, and also showed superiority over rest of the treatments. Among the herbicides, sulfosulfuron at 25 g/ha applied as post-emergence produced grain yield of wheat 3.49 t/ha, which increased the grain yield of wheat to the tune of 24.2, 35.8, 46.0, 49.8 and 103% over carfentrazone, clodinafop propargyl, pendimethalin, pinoxaden and weedy check, respectively.

Herbicide resistance, Phalaris minor, Yield, Wheat

A field study was conducted during winter season of 2017-18 at Department of Agronomy, CCS Haryana Agricultural University, Hisar under irrigated conditions to evaluate the management of P. minor through sequential application of pre-emergence (PE) and post-emergence (PoE) herbicide in wheat crop and their phytotoxic effect on the succeeding crop. Total fifteen treatments consisting of pre-emergence (PE) use of pendimethalin  1500 g/ha, clodinafop 60 and 120 g/ha (35 DAS), sulfosulfuron 25 g/ha (35 DAS), sulfosulfuron + metsulfuron 32 g/ha (35 DAS), pinoxaden 50 g/ha (35 DAS), mesosulfuron + iodosulfuron (RM) 14.4 g/ha (35 DAS), PE of pendimethalin + metribuzin (RM) 2000 g/ha, PE pendimethalin + metribuzin (RM) fb clodinafop 60 g/ha (35 DAS), PE pendimethalin + metribuzin (RM) fb sulfosulfuron 25 g/ha (35 DAS), PE pendimethalin + metribuzin (RM) fb sulfosulfuron + metsulfuron 32 g/ha(35 DAS), PE pendimethalin + metribuzin (RM) fb pinoxaden 50 g/ha (35 DAS), PE pendimethalin + metribuzin (RM) fb mesosulfuron + iodosulfuron (RM) 14.4 g/ha (35 DAS), weedy check and weed free were take. The results of present study revealed that PE followed by PoE herbicides are effective for the control of resistant P. minor population. The sequential application of PE pendimethalin + metribuzin (RM) 2000 g/ha fb mesosulfuron + iodosulfuron (RM) 14.4 g/ha followed by PE pendimethalin + metribuzin (RM) 2000 g/ha fb sulfosulfuron + metsulfuron (RM) 32 g/ha and pinoxaden 50 g/ha were the most effective for control of resistant P. minor compared to alone PE or PoE herbicide. Grain yield and economics were also higher with these treatments.

Clodinafop + metsulfuron, Sulfosulfuron + metsulfuron, Weed control efficiency, Weed density, Weed dry weight, Participatory rural appraisal

Farmers led on-farm trials were conducted in Morar and Bhitarwar blocks of district Gwalior during Rabi seasons of the year 2014-15 and 2015-16 in K.V.K. adopted villages to validate, refine and popularize the technologies recommended by Directorate of Weed Research, Jabalpur for managing grassy and broad-leaf weeds in wheat. Application of clodinafop + metsulfuron (60 + 2 g/ha) caused significant reduction in total weed counts (28.6 and 40.8/m2) and weed dry weight (3.5 and 4.2 g/m2) over farmer’s practice (2,4-D at 500 g/ha) as it reduced the population of both grassy and broad-leaved weeds and produced the highest weed control efficiency (83 and 82.6%) over application of sulfosulfuron + metsulfuron (30 + 2 g/ha) (70.87 and 76.03%) and farmers’ practice during both the year. Recommended practice of clodinafop + metsulfuron (60 + 2 g/ha) gave significantly higher grain yield (4.10 and 4.71         t/ha) over sulfosulfuron + metsulfuron (30 + 2 g/ha) and farmers practice. There were 21.42 and 22.46 and 12.18 and 9.87% increase in grain yield over farmers’ practice respectively under clodinafop + metsulfuron (60 + 2 g/ha) and sulfosulfuron + metsulfuron (30 + 2 g/ha) during the year 2014-15 and 2015-16. The highest net returns (` 51003 and 65267/ha) and B:C ratio (2.78 and 3.45) were recorded under recommended practice of clodinafop + metsulfuron (60 + 2 g/ha).

Oxyfluorfen, Quizalofop-ethyl, Weed, Sequential application, sunflower

Field experiment was conducted during the winter seasons of 2014-15 and 2015-16 to study the effect of sole and sequential application of herbicides on weed growth and productivity of sunflower (Helianthus annuus L.). Echinochloa colona, Digitaria sanguinalis and Dactyloctenium aegyptium among grasses; Cyperus rotundus and Cyperus difformis among sedges and Cleome viscosa, Euphorbia hirta and Borreria hispida among broad-leaved weeds, were predominant throughout the cropping period. Weed competition resulted in 31.3% yield loss in sunflower. Sequential application of oxyfluorfen 250 g/ha at 3 days after seeding (DAS) followed by (fb) quizalofop-ethyl 50 g/ha at 20 DAS resulted in the lowest weed density (41/m2), total weed biomass (19.37 g/m2), maximum nutrient uptake, yield (2.1 t/ ha) and benefit:cost ratio (1.82).