Effect of Herbicide (Propaquizafop and Imazethapyr) on Weed Flora Associated with Blackgram in Central India

An experiment was conducted at Product Testing Unit, Department of Agronomy, JNKVV, Jabalpur to study the effect of application of propaquizafop and imazethapyr herbicide on weeds associated with blackgram. The experimental field was having mixed weed flora comprising of grassy as well as broad leaved weeds. Nine treatments comprised of four rates of application of propaquizafop+ imazethapyr at 47+70, 50+75, 53+80 and 56+85 g/ha and alone application of propaquizafop (100 g/ha), imazethapyr (100 g/ha), pendimethalin (1500 g/ha) and hand weeding twice at 20 and 40 DAS including weedy check, were laid out in Randomized Block Design with three replications. All herbicide treatments were applied in 500 liters of water per hectare, using flat fan nozzle as per the treatments. The dominant weed flora, species wise weed density, weed biomass, Weed control efficiency and weed index were recorded at different interval. The study revealed that the Echinochloa colona (29.39%) and Dinebra retroflexa (24.30%) were the found as dominant weeds in the field whereas, other monocot weeds like Cyperus iria (18.19%) and dicot weeds like Mullugo pentaphylla (12.23%), Eclipta alba (7.58%) and Alternanthera philoxeroides (8.31%) were also present in less numbers in blackgram under weedy check plots. Among the herbicidal treatments, activity of propaquizafop+imazethapyr mixture at the dose 53+80 and 56+85 g/ha emerged as effective control for the weeds associated with blackgram.

Comparative Efficacy of Different Herbicidal Combinations on Weed Growth and Yield Attributes of Wheat

Weeds are the main biotic obstacles on wheat production, which can impair wheat productivity by up to 60%, if not handled under critical stages of crop life cycle. Chemical weed control through herbicides has been the most popular and effective method among farmers. The weed management using similar herbicides however has led to herbicide resistance in weeds. This requires the evaluation of newer herbicidal combinations for the control of weeds in wheat. Therefore, an experiment was conducted at Research Farm, Department of Agronomy, JNKVV, Jabalpur, Madhya Pradesh during the Rabi season of 2016-17 to evaluate the effect of post emergence application of herbicides on the weeds and yield of wheat. The experiment was laid out in randomized block design with ten treatments comprising of eight herbicidal combinations along with a hand weeding and a weed check and replicated thrice. Observations on different weed parameters, growth parameters and yield of wheat were recorded. Among the different herbicidal combinations, the post emergence application of halauxifen-methyl ester + florasulam at 10.20 g/ha resulted in greatest suppression of weeds and had highest weed control efficiency (56.73%). It also led to highest growth in wheat which resulted in highest grain yield (5.81 t/ha) and harvest index (44.99%). From this study, it can be concluded that the post emergence application of halauxifen-methyl ester + florasulam at 10.20 g/ha can not only control weeds effectively but also increase the yield of wheat.

Efficacy of Herbicides on Weed Control & Growth Parameter on Wheat

Wheat (Triticum aestivum) is a globally significant crop and a staple food for millions of people. Weed infestation is one of the major constraints affecting wheat productivity worldwide. The purpose of this study was to assess the efficiency of Carfentrazone ethyl 5% + Clodinafop propargyl 15% DF as a post-emergence herbicide against predominant weeds in wheat crops. Wheat is a globally significant crop and a staple food for millions of people. Weed infestation is a major constraint affecting wheat productivity. The study was conducted using a Randomized Block Design with three replications and a total of 11 treatments. The herbicide treatments were applied using foliar spray at different doses. Weed control efficiency was evaluated at 30, 45, and 60 days after herbicide application.The results showed that the highest weed control efficiency was observed in the weed-free plot, followed by the treatment with Carfentrazone ethyl 5% + Clodinafop propargyl 15% DF at a dose of 800 g/ha. This treatment provided significant control against different weed species such as Phalaris minor, Avena ludoviciana, and Chenopodium album. The herbicide treatments showed varying degrees of control efficiency, with some treatments performing better than others.These findings highlight the importance of weed management for increasing wheat crop production. The judicious use of herbicides, such as Carfentrazone ethyl 5% + Clodinafop propargyl 15% DF, can effectively control weeds and contribute to higher yields. However, further research and field trials are necessary to optimize the herbicide application and determine its long-term effects on wheat crops. Overall, this study emphasizes the need for effective weed control strategies to enhance wheat productivity and meet the demands of a growing population.

Evaluate the Correlation and Regression Studies of Growth, Yield Attributes and Yield of Transplanted Finger Millet (Eleusine coracana L. Gaertn) under Different Weed Management

Aim: To evaluate the “Correlation and Regression Studies of Growth, Yield Attributes and Yield of finger millet under different weed management.” Study Design: Randomized Complete Block Design (RBD). Place and Duration of Study: The field trial was conducted during the Rabi season of 2021-22 at Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu. The experimental field had a silky clay loam soil composition. Methodology: The field trial comprised of eight treatments and was replicated three times. In the experimental farm, the variety Paiyur 2 was grown into nursery and transplanted at 25th day with the spacing of 30 × 15 cm and followed the all other agronomic practices. To experimented the following treatments viz., T1- PE of pretilachlor at 1.0 kg ha-1,T2- PE of pretilachlor at 0.75 kg ha-1+ one hand weeding on 35th DAT, T3- PE of pendimethalin at 0.5 kg ha-1,T4- PE of pendimethalin at 0.5 kg ha-1+ one hand weeding on 35th DATP, T5- PE of Butachlor at 1.0 kg ha-1,T6- PE of Butachlor at 0.75 kg ha-1+ one hand weeding on 35th DAT, T7- POE of 2,4-D at 2 kg ha-1on 35 th DAT, T8- POE of 2,4-D at 2 kg ha-1+ one hand weeding on 35th DAT, T9- Two hand weeding at 35 DAT and 70 DAT, T10- Unweeded check. The biometric observations were recorded at three specific time points: 35 DAT, 70 DAT, and at harvest stage. Results: The grain yield was highly significant positive correlation with Straw yield (r = 0.893), Leaf area index (r =0.975), Dry matter accumulation at 70 DAT (r=0.966), Dry matter accumulation at harvest (r =0.966), Productive tillers (r =0.902), Test weight (r =0.903), Weed control efficiency (r =0.797), Nitrogen uptake (r =0.980), Phosphorus uptake (r =0.972), Potassium uptake (r =0.960). However, significant positive correlation with Plant height (r =0.733). From the regression every unit increase in stover yield, plant height, LAI at 70 DAT, crop dry matter at 70 DAT, crop dry matter at harvest, number of productive tillers plant-1, test weight, Weed Control Efficiency and N, P and K uptake by crop substantially increased the grain yield by 0.798, 0.537, 0.951, 0.932, 0.992, 0.812, 0.865, 0.635, 0.960, 0.944 and 0.920 kg ha-1 respectively.

Performance of Pinoxaden Herbicide against Complex Weed Flora in Wheat (Triticum aestivum L.)

A field experiment was conducted during rabi season (2020-21) at AICRP on Wheat, College of Agriculture, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur (MP), India, to study the effect of pinoxaden on weeds and the yield of wheat. The field experiment was laid out in a randomized block design with seven treatments and replicated thrice. Treatments included applying different doses of pinoxaden at 40, 45, and 90 g a.i. ha-1, clodinafop propargyl at 90 g a.i. ha-1, sulfosulfuron at 25 g a.i. ha-1 as post-emergence along with hand weeding at 30 DAS and weedy check. The experimental field was dominated by Phalaris minor (15.6%) among monocot weeds, while Medicago denticulata (30.82%), Cichorium intybus (29.94%), Chenopodium album (15.32%), and Anagallis arvensis (8.30%) among the dicot weeds throughout the crop growing period. Among the different herbicidal treatments, pinoxaden at 90 g a.i. ha-1 effectively controlled the monocot and dicot weeds and recorded higher weed control efficiency and the lowest weed index. However, the highest value of growth parameters, yield attributes, and grain yield was recorded with the application of pinoxaden at 45 g a.i. ha-1 among all the herbicidal treatments.

Weed Dynamics of Fodder Maize as Influenced by Different Herbicides

The advancements in fodder maize cultivation practices over the past few years, has paved a change in the makeup of weed associations. This made it necessary to incorporate new, effective herbicides in the struggle against maize's primary weeds. Therefore, a field experiment was conducted at Research Farm, AICRP on Forage Crops, Department of Agronomy, JNKVV, Jabalpur (Madhya Pradesh) during Kharif season 2019 to devise an appropriate combination of herbicides required for the control of the complex weed diversity in fodder maize. The field experiment was laid out in randomized block design (RBD) with ten treatments (eight herbicidal combinations along with hand weeding twice at 20 and 40 DAS and a weedy check) and replicated thrice. Observations were recorded on the weed parameters and fodder yield of maize. Among monocots, the experimental field was infested with Echinochloa colona, Commelina communis and Digitaria sanguinalis. Phyllanthus niruri and Eclipta alba were dominated among dicots. Among all herbicidal treatment, topramezone 35 g/ha plus atrazine 250 g/ha was found to be significantly superior in reducing total weed density (9.49/m2, 11.50/m2) and total weed dry weight (6.43 g/m2, 7.91 g/m2) at 30 and 45 DAS, respectively and recorded the lowest weed index (1.82%). Also, the maximum green fodder yield (472.68 q/ha) was recorded in topramazone 35 g/ha + atrazine 250 g/ha compared to other treatments. Overall, this study indicated that the combination of topramazone 35 g/ha + atrazine 250 g/ha could be an alternative approach to hand weeding and alone herbicides in fodder maize.

Evaluation of Low Dose Herbicides in Transplanted Rice (Oryza Sativa L.).

A field experiment was conducted during kharif 2011 at College of Agriculture, Rajendranagar. The experiment consisted of 12 treatments laid out in randomized block design with three replications consisting of two pre-emergence herbicides integrated with post emergence herbicides and one hand weeding at 40DAT and two post emergence herbicide, hand weeding twice at 20 and 40 days after transplanting, compared with weed free and unweeded check. The predominant weed flora observed in the experimental field were Echinochloa crusgalli, Panicum repens, Cynodon dactylon, Cyperus rotundus, Cyperus difformis, Eclipta alba and Ammania baccifera. The results revealed that pre-emergence application of Bensulfuron methyl 0.6% + Pretilachlor 6% @ 10 kg granules ha- 1+ Hand weeding at 40 DAT (5455 kg ha-1 and 6345 kg ha-1) and Bensulfuron-methyl 0.6% + Pretilachlor 6% @ 10 kg granules ha-1 + Bispyribac sodium @ 25 g a.i ha-1 recorded significantly higher grain and straw yield (5365 and 6265kg ha-1, respectively) which remained at par with two hand weedings at 20 and 40 DAT (5580 and 6464 kg ha- 1). In terms of economics, highest net returns (Rs. 33,189 ha-1) and B:C ratio (1.40) were also high with the preemergence application of Bensulfuron-methyl 0.6%+ Pretilachlor 6% @ 10 kg granules ha-1+ Bispyribac sodium @ 25 g a.i. ha-1 at 20DAT (1.40) compared to that of two hand weedingds (Rs. 31,952 ha-1) and benefit cost ratio (1.17) .