Ecomorphometric markers reflect variations in Azadirachtin-A content of Azadirachta indica A. Juss (Meliaceae) in select regions of Andhra Pradesh, India

Ecomorphometric markers reflect quantitative variations in the potent antifeedant, azadirachtin-A from neem. Fifty accessions from five ecogeographically distinct regions in Andhra Pradesh, India were studied. Significant disparity in azadirachtin-A density, 100 seed weight and total azadirachtin-A was observed in accessions between the extremely-arid-alkaline and delta-wet regions. Statistical tools such as Linear Multiple Regression Analysis, Duncan's New Multiple Range Test and Pearson Correlation were used to find out the relationship between independent variables (leaf, fruit/seed and soil parameters) and dependent variables (azadirachtin-A density and total azadirachtin-A content).