DEVELOPMENTAL STAGES OF AGROTIS-YPSILON HUFN (LEP, NOCTUIDAE) AS AFFECTED BY BACILLUS-THURINGIENSIS BERL

The prepupal and pupal stages of A. ypsilon were affected by B. thurin giensis when sprayed or kept in the soil treated with the pathogen. Th e emerged moths showed a short longevity associated with low egg produ ction and low fertility. B. thuringiensis showed an increased effect o n the pupae when treatment was applied immediately after pupation. The effectiveness of B. thuringiensis against the moths and eggs of A. yp silon have been also demonstrated. The longevity, egg production and f ertility were significantly affected when the moths were fed on a diet containing the pathogen at certain concentrations. Also, moths releas ed on castor oil plant sprayed with B. thuringiensis (1000 and 500 mug /ml of Dipel 2X) showed a reduced egg production and fertility. Sucros e diets containing spores of B. thuringiensis only or without viable s pores (UV irradiated B. thuringiensis solution) caused adverse effects on the longevity, egg production and egg hatching, but with reduced m oth mortality. Egg masses sprayed with B. thuringiensis hatched normal ly, but the survival of the hatched larvae was reduced when treatment was made shortly before egg hatching. Based on these results, B. thuri ngiensis showed a promising effect in the control of the moths A. ypsi lon and may serve as an ovicide-larvicide agent.