author(s)
Bhupen Kumar Sahu, Ipsita Samal and Junmoni Boruah

abstract
A gall is a growth of plant tissue that starts with the chemical and/or mechanical stimulus of an organism, which increases the production of plant growth hormones. An insect gall forms due to the response of plant to the insect life cycle – starting from egg laying up to adult emergence from the gall. The host plants of silkworms play a very crucial role for the production of raw silk whereas on the other hand the nutritional value of food plants are the possibilities of obtaining good cocoon crop. One of the important yield factors affecting the yield of the silk is the attack of insect pests on silkworm. Among the various insect pests, the gall insect damages the leaves and tender parts of the stem of some host plants by forming galls. Galls are infested by gall midges, gall wasps, aphids, psyllids and phylloxerans. There are also some of the gall forming species which were found in different host plants of silkworm.