Biochemical basis of resistance against major castor pests

A field experiment was carried out during Rabi,2021 at RARS, palem to study the biochemical factors responsible for insect resistance. The biochemical parameters viz., crude fibre, crude protein, tannins, phenols and carbohydrates were quantified in five castor hybrids to find out their association with tolerance or resistance against two defoliators Achaea janata and Spodoptera litura and two sucking insects, leafhoppers and thrips. Crude fibre and carbohydrates had a positive correlation with the insect population whereas phenols, tannins and crude protein showed a significant negative correlation. DCH-519 and NBCH-22 with least crude fibre, carbohydrates and higher phenols are considered to be resistant to insect population.