OVIPOSITION OF TOBACCO BUDWORM (LEPIDOPTERA, NOCTUIDAE) IN MIXED PLANTINGS OF NONTRANSGENIC AND TRANSGENIC COTTONS EXPRESSING DELTA-ENDOTOXIN PROTEIN OF BACILLUS-THURINGIENSIS (BERLINER)

Oviposition of Heliothis virescens (F.) on transgenic cottons Gossypiu m hirsutum (L.) expressing delta endotoxin protein of Bacillus thuring iensis (Berliner) was studied during 1993 through 1995. The experiment al cotton cultivars Event 531 and 'NuCOTN 33B', both expressing the de lta endotoxin protein, were compared to oviposition on the parent, non expressing, cottons (Coker 312 and DP 5415, respectively) in cage and field studies. No significant differences in oviposition between the c otton genotypes were found. Additionally, no significant difference be tween the cotton genotypes was shown for vertical. placement of eggs w ithin the plant canopy or selection of different plant structures as o viposition sites. Data indicated that Coker 312 plants were taller tha n Event 531 plants for the seed lots tested. Trends for more ovipositi on on Coker 312 may be due to this height differential.