THE USE OF BACILLUS-THURINGIENSIS TO CONTROL 2 LEPIDOPTEROUS INSECT PESTS (AGROTIS-YPSILON AND SPODOPTERA-LITTORALIS)

An area of 50 feddans cultivated with soybeans was treated with Bacill us thuringiensis (B.t.) baits against Agrotis ypsilon and 60 feddans w ere sprayed with B.t. spray against Spodoptera littoralis. When B.t. b aits were used, the percentage of kill of A. ypsilon reached 96.1-96.4 % compared to 97.4-98% kill on using hostathion baits. When B.t. was s prayed against S. littoralis, a percentage of larval kill 88.3% was ob tained. This increased to 97.3% after the second application. On the o ther hand, the percentage of kill reached 96.8% when lannate was spray ed once. The average yield was 1.54 tons/fed. when B.t. was sprayed tw ice against S. litto-ralis and 1.42 tons/fed. when sprayed once. Areas treated with lannate gave 1.44 tons/fed., while in the untreated area , the yield was comparatively low being 0.83 tons/fed.