Effects of Integrated Weed Management Practices on Weed Parameters and Yield of Bt Cotton (Gossypium hirsutum L.)

Aim: To know the effect of integrated weed management on weed parameters and yield of bt cotton.Study Design: Randomized complete block design.Place and Duration of Study: College of Agriculture Farm, Bheemaraynagudi between July 2021 and Feb 2022.Methodology: The field experiment was conducted during Kharif 2021 at Experimental block, College of Agriculture, Bheemarayanagudi. The soil of the experiment field was deep black clayey in texture. The experiment comprises 11 weed management practices viz., T1: Pendimethalin 38.7% CS @ 750 g a.i./ha as PE + Hand weeding @ 20-25 DAS and Intercultivation @ 55-60 DAS, T2: Pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb Pyrithiobac Sodium 10 EC @ 75g a.i./ha + Quizalofop ethyl 5 EC @ 37.5g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS. (Tank mix), T3 : Pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb Pyrithiobac Sodium 10 EC @ 50g a.i./ha + Quizalofop ethyl 5 EC @ 25 g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T4 :Pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb Pyrithiobac Sodium 10 EC @ 75g a.i./ha + Quizalofop ethyl 5 EC @ 37.5g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T5 : Pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb Pyrithiobac Sodium 10 EC @ 100g a.i./ha + Quizalofop ethyl 5 EC @ 50g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T6 : Pyrithiobac Sodium 10 EC @ 50g a.i./ha + Quizalofop ethyl 5 EC @ 25g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T7: Pyrithiobac Sodium 10 EC @ 75g a.i./ha + Quizalofop ethyl 5 EC @ 37.5g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T8: Pyrithiobac Sodium 10 EC @ 100g a.i./ha + Quizalofop ethyl 5 EC @ 50g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS, T9: Farmers practice (Hand weeding @ 25 DAS and 2 intercultivations @ 50 and 75 DAS), T10: Weedy check, T11: Weed free check.Results: Among the treatments, application of pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb pyrithiobac sodium 10 EC @ 100 g a.i./ha + quizalofop ethyl 5 EC @ 50 g a.i./ha as PoE (combi-product) @ 25 DAS and intercultivation @ 55-60 DAS recorded significantly lower weed density and higher weed control efficiency (82.39 %), also recorded higher seed cotton yield (2495 kg ha-1) and stalk yield (4056 kg ha-1) over other treatments.Conclusion: Application of Pendimethalin 38.7 % CS @ 750 g a.i./ha as PE fb Pyrithiobac Sodium 10 EC @ 100g a.i./ha + Quizalofop ethyl 5 EC @ 50g a.i./ha as PoE @ 25 DAS and Intercultivation @ 55-60 DAS was found effective in controlling the weeds with coupled with higher seed cotton yield .

Effect of Nano Fertilizers on Growth, Yield, Nutrient Uptake and Soil Microbiology of Kharif Sorghum

Aims: Foliar nutrition is aimed to eliminate the problems of fixation and immobilization of nutrients. Hence, foliar nutrition is being recognized as a significant way of fertilizing modern agriculture, especially under rainfed conditions. Nano fertilizers because of smaller size and higher surface area are efficient as compared to conventional and produce better results when used in combined form.Study Design: The experiment was laid out in Randomized complete block design with three replications.Place and Duration of Study: A field experiment was conducted in medium black soils at Agricultural Research Station, Hagari, during Kharif 2022.Methodology: There were ten treatment combinations, consisting of different doses of RDF (50 % RNP, 75 % RNP and 100 % RDF and absolute control) with different doses of nano urea and Dap sprayed at 30 and 45 DAS for CSH-16 hybrid of sorghum.Results: Application of 75% RNP as basal + nano urea & DAP spray @ 1.5 ml l-1 each at 30 and 45 DAS recorded significantly higher number of leaves, leaf area and leaf area index. It also produced higher earhead length (35.9 cm), number of grains earhead-1 (2207), grain weight (57 g plant-1) and test weight (29.3 g 1000 grains-1). Nutrient content and uptake also showed higher values for the same treatment along with the nutrient use efficiency indices. Whereas, significant reduction in soil microbes was noticed by the application of treatment.Conclusion: Combined application of conventional and nano fertilizers helped to increase growth, growth attributes like number of leaves, leaf area, leaf area index, yield attributes, nutrient content, nutrient uptake and nutrient use efficiency of sorghum.

Determination of Crop Water Requirement and Crop Coefficient at Different Growth Stages of Tomato by Using Weighing Type Lysimeter in Raichur Region

The water requirement for any cropping system is important consideration for designing and managing irrigation systems. Water requirement of crops varies substantially over the growing season mainly due to variation in crop cover and climatic conditions. For estimating crop water requirement of tomato crop, we have taken field experiment in weighing lysimeter for three seasons rabi - (7th September 2021 to 5th January 2022); Summer - (15th January 2022 to 15th May 2022) and Kharif - (6th June 2022 to 4th October 2022). The crop water requirement helps us to develop the crop coefficients for various growth stages (initial, development, mid and late season) for particular climatic conditions. Further, with exact crop coefficients derived from weighing type lysimeter will be helpful for determining water requirement. The results showed that the crop evapotranspiration (ETc) for initial, development, mid-season and late-season being 22.76, 110.71, 173.47 and 68.71 mm, respectively. With respect to crop coefficient (Kc), it is estimated to be 0.38, 0.64, 1.12 and 0.66 for initial, development, mid-season and late season stages, respectively during rabi season. The crop evapotranspiration (ETc) for initial, development, mid-season and late-season being 26.53, 164.76, 235.56 and 121.51 mm, respectively. With respect to crop coefficient (Kc), it is estimated to be 0.56, 0.87, 1.22 and 0.78 for initial, development, mid-season and late season stages, respectively during summer season. The crop evapotranspiration (ETc) for initial, development, mid-season and late-season being 32.31, 131.38, 173.51 and 60.13 mm, respectively. With respect to Kc, it is estimated to be 0.36, 0.77, 1.13 and 0.74 for initial, development, mid-season and late season stages respectively during kharif season. The measured Kc values were significantly different from the FAO-56 reported values. Therefore, local calibration of crop coefficients is an essential for efficient irrigation water management and precise water applications.