Influence of Fertilization Levels on Canopy Reflectance and Biochemical Parameters at Different Growth Stages of Bt-Cotton

A field experiment was conducted during kharif, 2013 at agricultural college farm, Raichur. The experimental design was laid out in randomized complete block (RCBD) with nine treatments replicated thrice. Application of higher doses of nutrients i.e. 150% RDF (225: 112.5: 112.5 NPK kg/ha) recorded significantly higher NDVI (lower canopy reflectance). The biochemical parameter such as chlorophyll and carotenoid content, leaf nitrogen content and SPAD meter readings were higher in the treatment 150% RDF. Similarly, significantly higher yield and yield components were recorded with application of 150% RDF i.e. number of bolls per plant (51.0), boll weight (6.56 g), seed cotton yield (3237 kg/ha), followed by 150% RDN, 100% RDN, 50% RDN, 50% RDF and 0% RDN. The lowest values were observed for all parameters from application of STCR (Target 2.0 t/ha) (0: 25.5: 24.4 kg NPK/ha).