SHELTER BUILDING BY LARVAE OF PHYCITA DIAPHANASTAUDINGER, 1870 (LEPIDOPTERA PYRALIDAE) USING RICINUS COMMUNISL. IN ARID ZONE

In July 2017, in south-eastern Tunisia, larvae of Phycita diaphanawere observed on seedlings of castor bean. Infested pointed lobes of the leaves are characterized by the presence of shelters or nests ranging from oneto six shelters per leaf. The shelter area ranged from 1.01 to 28.27 cm2. In each shelter, we found from one to nine larvae. We conclude thatPh. diaphana spends the whole larval stage protected without changing its feeding habits.The leaf roll may reduce leaf toughness and lower levels of plant defensive chemicals, and hence provides a more easily and more safely eaten food. Larvae of Ph. diaphana use the pointed lobe to build its shelter. As Castor bean is used in several fields of economy, mainly the production of biodiesel fuel, the monitoring of this pest will be important and interesting. Thereby, studying the life cycle of pests constitute a significant element of phytosanitary control.