Wanjari, Dr. S. SISAL, RAJABHAU LAXMAN2021-11-262021-11-262020-08-27ISAL, RAJABHAU LAXMAN. (2019). PERFORMANCE OF Bt COTTON UNDER ETc BASED DRIP IRRIGATION AND POLYMULCH TECHNIQUE. Department of Agronomy, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Ph.D 2019.Print. XVIII, 229p. (Unpublished).https://krishikosh.egranth.ac.in/handle/1/5810178350Based on the results of two years study conducted to evaluate the influence of polythene mulch and different irrigation levels through drip irrigation on growth, yield, quality, and economic feasibility of cotton, the following inferences were drawn: 1. Polythene mulch significantly improved the growth contributing characters, growth, yield attributes and yield over without polythene mulch. 2. Similarly, the growth and yield of Bt cotton increased significantly with the irrigation level of 0.8 ETc as compared to other irrigation levels. 3. Under economic analysis, it was evident that Bt cotton grown under polythene mulch and water applied with 0.8 ETc provided maximum gross monetary returns, net monetary returns and benefit to cost ratio.A field experiment entitled "PERFORMANCE OF Bt COTTON UNDER ETc BASED DRIP IRRIGATION AND POLYMULCH TECHNIQUE."was conducted at the Department of Agronomy, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Maharashtra (India) during kharif 2013-14 and 2014-15 on clayey soil. The cotton crop was sown on 12th June during both the years. The experiment was sown on broad bed furrow laid out with eight treatment combinations in Factorial Randomized Block Design replicated thrice. Treatment comprises of without polythene mulch and with polythene mulch and four irrigation levels as 0.4 ETc, 0.6 ETc,0.8 ETc and 1.0 ETc were constituted the factor I and the factor II respectively and check treatment was taken as farmers practice, where sowing was done on ridges and furrow with polythene mulch and without polythene mulch. 12The soil of experimental plot was medium deep black with fairly uniform and levelled topography. The rainfall at initial stages of crop growth was more than normal during first year and less than the normal during second year of experimentation. During 2013-14, the weather parameter were about normal, whereas during 2014-15, weather parameters fluctuations were sometimes extreme and not so satisfactory for crop growth . Plant height along with growth parameter viz., number of leaves, number of sympodial branches, leaf area and total dry matter plant-1 were significantly improved under polythene mulch during 2013-14 and 2014-15. Application of polythene mulch recorded significantly higher number of bolls plant-1 and seed cotton yield plant-1 seed cotton yield ha-1, stalk and biological yields ha-1 over without polythene mulch during both the years of experimentation. The soil moisture content, water use efficiency and soil temperature were higher under polythene mulch than without polythene mulch. Uptake of nitrogen, phosphorus and potassium were also higher under polythene mulch. The gross and net monetary returns and B:C ratio were marginal under polythene mulch. Among the four irrigation levels, irrigation level of 1.0 ETc showed higher values of growth parameters such as functional leaves, sympodial branches, leaf area plant-1 and total dry matter plant-1. Whereas, it was comparable with irrigation at 0.8 ETc. As regards yield attributes, number of bolls plant-1, boll weight and seed cotton yield plant-1 were significantly higher with irrigation level 0.8 ETc over 0.4 ETc and 0.6 ETc but was found on par with irrigation level 1.0 ETc. Irrigation level of 0.8 ETc recorded higher seed cotton yield, stalk yield and harvest index. The soil moisture content was significantly higher under the irrigation level at 1.0 ETc, however, water use efficiency was higher under irrigation level 0.4 ETc followed by 0.6 ETc and 0.8 ETc. The higher uptake of nitrogen, phosphorus and potassium, gross monetary returns, net monetary returns and B:C ratio were recorded with the irrigation level 0.8 ETc fallowed by 1.0 ETc,0.6 ETc and 0.4 ETc irrigation levels. Polythene mulch produced higher growth contributing,yield and yield attributes over without polythene mulch due to higher growth of plant under the polythene mulch. Irrigation level of 1.0 ETc gave the highest values as regards to growth and growth contributing characters, however yield and yield attributes were higher in irrigation level 0.8 ETc As regards to check treatments (farmers practice) sowing on ridges and furrow with polythene mulch gave higher values of growth parameters viz., number of leaves, number of sympodial branches, leaf area plant-1, total dry matter plant-1, yield attributes, gross monetary returns, net monetary returns, and B:C ratio over sowing on ridges and furrow without polymulch during 2013-14 and 2014-15. On the basis of two years data, it could be concluded that application of polythene mulch (silver-black) with 0.8 ETc irrigation throug drip found better for increasing the productivity and economic returns of cotton while saving the water.EnglishThesis