Feasibility of Multispectral Observations for Detecting Nitrogen Stress and Yield Potential in Cotton (Gossypium hirsutum L.) through Remote Sensing

The present investigation was conducted during kharif 2019-20 at Department of Agronomy farm, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. The experiment was laid out in randomized block design with seven treatments and three replications. Treatments consisted of different nutrient management practices including FYM and nitrogen doses viz., Absolute Control (N1), FYM @ 5 t ha-1 (N2), N2 + 30 kg N ha-1 (N3), N2 + 60 kg N ha-1 (N4), N2 + 90 kg N ha-1 (N5), N2 +120 kg N (N6) and N2 + 150 kg N ha-1 (N7). Cotton crop was sown on 29th June 2019 and was harvested in four pickings. Among various spectral bands, significantly higher positive and negative correlation coefficient values (at 0.05 % level of significance) for plant chlorophyll content were noted with the simple ratio of NIR/G (r2=0.829) and G/NIR(r2=-0.826), respectively, being most efficient in detecting the nitrogen stress in cotton crop. Yield potential of cotton was established (at 0.05 % level of significance) with negative and positive (both) correlation coefficient of simple ratio of R/NIR (r2=-0.815 and r2=-0.869) and NIR/R (r2=0.811and r2=0.865) respectively at 180 DAS.