Allelopathy Journal

We studied the effects of four major pests [capsule borer, Dichocrocis punctiferalis (Guenée), semilooper, Achaea janata (L), tobacco cutworm, Spodoptera litura (Fabricius) and sucking pest, Empoasca flavescens (Fabricius)] feeding on the castor Ricinus communis (L) plants, on primary metabolites and biochemical constituents of leaves. We measured the primary metabolites (amino acids, glutamine, urea, ammonia, carbohydrates, proteins, phenols and oxidative and hydrolyzing enzymes) involved in the synthesis of secondary metabolites. The quantities of biochemical constituents (except glutamine) were increased by the feeding of leaf eating insects than sucking pests or mechanically damaged plants. All the enzymes activities enhanced in the semilooper, tobacco cutworm and capsule borer damaged plants. We concluded that the defence mechanism of plant differs with the type of attacker pest and were related to the enhanced enzymatic activities.