BIOLOGY OF POTATO-TUBER MOTH, PHTHORIMAEA-OPERCULELLA ZELLER WITH SPECIAL REFERENCE TO PUPAL EYE PIGMENTATION AND ADULT SEXUAL DIMORPHISM

Life history studies on potato tuber moth, Phthorimaea operculella Zeller, a serious pest of potato were carried out on a laboratory maintained culture. The present paper deals specifically with the pupal period during which five stages have been differentiated on the basis of eye pigmentation. The sexually dimorphic characters of the adults have been described. The male and the female adults differ from each other not only on the basis of morphological characters but also in longevity. Total life cycle of the insect pest is completed in 21 days.