Evaluating Weed Management Strategies and the Differential Effects of Herbicides on Weed Dynamics and Crop performance of Foxtail Millet Grown under the Irrigated Conditions of Rayalaseema

At the wetland farm of S.V. Agricultural College, Acharya N.G. Ranga Agricultural University, Tirupati, Andhra Pradesh, India, a field experiment was carried out during the (rainy season) kharif 2020 to evaluating weed management strategies and the differential effects of herbicides on weed dynamics and crop performance of foxtail millet [Setaria italica (L.) Beauv] grown under the irrigated conditions of Rayalaseema. The current study has shown that the application of pre-emergence pretilachlor 500 g ha-1 with intercultivation at 20 DAS was followed by hand weeding twice at 20 and 40 DAS and it led to the highest weed control efficiency, including foxtail millet's nutrient uptake, and the lowest weed density and dry weight. In unweeded check, a heavy weed infestation reduced the amount of nitrogen, phosphorus, and potassium absorbed by crop by 45.67, 18.03, and 35 kg ha-1, respectively. Crop growth parameters, straw and grain production was increased by hand weeding twice, however the benefit-cost ratio lagged behind the most effective weed management strategy, which is applying pre-emergence of pretilachlor 500 g ha-1with intercultivation at 20 DAS. The present experiment indicated that wherever the labour availability for hand weeding is abundant and cheaper, one can go for hand weeding or opt for the said herbicide recommendation taking into the economical considerations.

Effect of Pretilachlor 50% EC on Weed Control of Transplanted Rice under Alluvial Soil of West Bengal, India

Field experiments were conducted at Regional Research Station of Bidhan Chandra Krishi Viswavidyalaya, Gayeshpur, West Bengal during winter season of 2014 and 2015 to evaluate the bio-efficacy against weeds & phytotoxicity of pretilachlor 50% EC on transplanted rice. The experiment was tested under randomized complete block design with three replicates. Among the herbicides, highest weed control index was recorded in pretilachlor 50% EC @ 2 kg a.i. ha-1 which imparted phytotoxic symptoms in rice plants resulting in yield reduction. However, the highest grain yield (3.59 t ha-1) was obtained with the application of pretilachlor 50% EC @ 1.2 kg a.i. ha-1 which was statistically at par with twice hand weeding. From these findings it can be concluded that the application of pretilachlor 50% EC @ 1.2 kg a.i. ha-1 can be recommended for effective weed management in transplanted rice in the study area.

Effect of Weed Management Practices on Growth, Yield and Quality of Okra [Abelmoschus esculentus (L.) Moench]

The present investigation entitled “Effect of weed management practices on growth, yield and quality of okra Abelmoschus esculentus (L.) Moench)” was conducted at Vegetable Research Farm, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur during kharif season 2022. The experiment was laid out in Randomized Block Design with seven different treatments viz. T1 = Pre-emergence application of Pendimethalin @ 6 ml /L, T2= Post emergence application of Quizalofop-ethyl @ 0.040 kg/ha ,T3 = Pre-emergence application of pendimethalin @ 6 ml/L + one hand weeding at 40 DAS , T4 = Post emergence application of Quizalofop-ethyl @ 0.040 kg ha-1 at 25 DAS + one hand weeding , T5 = Pendimethalin @ 6 ml /L as pre-emergence + Quizalofop-ethyl @ 0.040 kg ha-1 at 25 DAS , T6 = Weed free check (Three hand weeding) 20, 40 and 60 DAS , T7 = weed check control replicated thrice. The result of the study revealed that at 30 DAS maximum plant height (30.96cm) was reported in treatment T3 : Pre-emergence application of Pendimethalin @ 6 ml/L + one hand weeding at 40 days of sowing whereas at 60 and 90 DAS maximum plant height (75.50 and 113.53 cm) was reported in T6 : Weed free check (Three hand weeding) 20, 40 and 60 DAS. Maximum number of branches per plant (4.60)at 60 DAS was found in T3 : Pre-emergence application of Pendimethalin @ 6 ml/L + one hand weeding at 40 DAS and 90 DAS maximum number of branches per plant (5.86) was reported in T6 : Weed free check (Three hand weeding) 20, 40 and 60 DAS. Maximum number of nodes (17.83 ) at 60 days after sowing was noticed in treatment T3 = Pre-emergence application of Pendimethalin @ 6 ml/L + one hand weeding at 40 DAS and 90 Days after of sowing maximum number of nodes () was in treatment T6 = Weed free check (Three hand weeding) 20, 40 and 60 DAS. Maximum Pod diameter( 1.74cm) , fruit weight (12.88gm ), pod length( 14.1cm) , number of pods per plant( 25.66 ) , pod yield per plant ( 304.73gm) , pod yield per hectare (16.91 t), TSS( 3.2 Brix), crude fibre (8.46%) and cholorophyll content (1.18 mg) and relative cholorophyll content (54.39) .

Effect of Weed Management Practices on Growth, Yield of Vegetable Cowpea (Vigna unguiculata (L.) Walp.) cv. Kashi Kanchan

The present investigation contains seven different treatments viz., weedy check (control), weed free check (3 hand weeding) (first hand weeding at 25 DAS), pre-emergence application of Pendimethalin @ 6ml/L, pre-emergence application of Pendimethalin @ 6ml/L + one hand weeding, pre- emergence application of Pendimethalin @ 6ml/L + post emergence @ 40-50 g/ha at 25 DAS, post-emergence application of Metribuzin @ 525g/ha at 25DAS and post-emergence spray of Imazethapyr @ 100 g ai/ha at 25 DAS replicated thrice. The cowpea variety ‘Kashi Kanchan’ was used in experiment. Results of the experiment revealed that though, the weed free check (T2) recorded zero weed population and slightly higher values of growth and yield parameters but among tested treatments, pre-emergence application of Pendimethalin @ 6ml/L + one hand weeding (T4) and pre-emergence application of Pendimethalin @ 6ml/L + Quizalofop ethyl @ 40-50 g/ha at 25 DAS(T5) significantly reduced weed number (48.12 and 52.18/m2) and produced significantly highest plant height (47.30 and 45.98 cm), pod length (21.64 and 20.86 cm), number of pods/plant (35.94 and 34.18), average pod weight(11.18 and 11.06 g), green pod weight/plant (367.84 and 348.63g), green pod weight/plot (11.24 and 10.54 kg) and green pod yield per hectare(118.96 and 111.55q). However, these three treatments (T2, T4 and T5) were statistically at par with each other in terms of growth and yield parameters.Hence, these two weed management practices (T4 and T5) may serve as alternative of manual weeding and may be recommended for farmers of the central plain zone of Uttar Pradesh for higher returns from vegetable cowpea crop.

Weed Management in Clusterbean under the Application of Different Agrochemicals and Phosphorus Levels

Among the Kharif legumes clusterbean (Cyamopsis tetragonoloba L. Taub) is important crop and popularly known as “Guar” in India. A field experiment was conducted during Kharif 2013 at Agronomy Farm, S.K.N. College of Agriculture, Jobner, Jaipur (Rajasthan) to evaluate the weed management in clusterbean under the application of different agrochemicals and phosphorus levels. The treatments comprising 6 weed control treatments (Weedy check, one hand weeding at 20 DAS, two hand weeding at 20 and 40 DAS, pendimethalin at 0.75 kg/ha, imazethapyr at 100 g/ha and fenoxoprop-p-ethyl at 70 g/ha and four levels of phosphorus (0, 20, 40 and 60 kg/ha) assigned to main and sub plots of spilt plot design, respectively and replicated thrice. Results showed that HW twice at 20 and 40 DAS and pre emergence application of imazethapyr at 100 g/ha resulted significant reduction in weed density and weed dry matter in comparison to most of the treatments. Results further indicated that application of 60 kg P2O5/ha in clusterbean recorded the highest density and dry weight of weeds at all the stages. Maximum weed control efficiency was recorded under two hand weeding at 20 & 40 DAS.

Effect of Nitrogen and Weed Management Practices on Growth and Yield of Blackgram (Vigna mungo L.)

A research trail was conducted in Kharif 2022, at Crop research form, SHUATS, Prayagraj. To study the “Effect of nitrogen and weed management practices on growth and yield of Blackgram” (Vigna mungo L.). The treatments consist of three levels of nitrogen (15, 30 and 45 kg/ha) and weed management practices (Hand weeding twice (20 & 40 DAS), Pendimethalin (0.75ml/ha) Pre-emergence (5 DAS), Imazethapyr (75g/ha) Post-emergence (25 DAS) are included. Experiment were laid out in randomized block design with 10 treatments each replicated thrice. The result showed that viz: significantly higher plant height (64.49 cm), number of nodules/plant (23.80), number of branches/plant (6.40), pods/plant (32.13), seeds/pod (8.20), grain yield (1223.33 kg/ha), Stover yield (2472.67 kg/ha), lower weed population/m2 (4.06) recorded in (treatment 9) Nitrogen (45 kg/ha) + Imazethapyr (75 g/ha) Post-emergence.

Assessment of Different Weed Management Practices in Mustard for Enhancement of Productivity

A field experiment was conducted at Krishi Vigyan kendra, Sawaimadhopur, Rajasthan, India in two consecutive years during 2018-19 and 2019-20 on Zone III –B of Rajasthan, India. In this experiment was performed in randomized block design which includes four treatments of weed control i.e. weedy check (T1), Hand weeding at 25 DAS (T2), Hand weeding at 25 & 45 DAS (T3), Pre emergence application of Pendimethaline @ 1.0 kg a.i. ha-1 (T4) and replicated five times. Results revealed that Weed Density (no m-2) 60 days after sowing, Dry weight (kg ha-1) 60 days after sowing, weed control efficiency (%) and weed index found lowest in two hand weeding at 25 and 45 days after sowing fb Pre emergence application of Pendimethaline @ 1.0 kg a.i. ha-1 (T4) during both the years during 2018-19 and 2019-20, respectively. Highest seed yield (2341 kg ha-1) and (2431 kg ha-1) was found under two hand weeding (25 & 45 days after sowing) during 2018-19 and 2019-20 respectively.