Boil damage by southern green stink bug (Hemiptera: Pentatomidae) and tarnished plant bug (Hemiptera: Miridae) caged on transgenic Bacillus thuringiensis cotton

Damage to bells of transgenic Bacillus thuringiensis (Bt) cotton by southern green stink bug, Ne;nra viridula (L.), and tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), was evaluated in field-cage studies. Fifth instars of N. viridula confined singly over a 9-d-old bell for 3.5 d caused more damage than adult stink bugs or earlier instars. Boil damage by 5th instars of N, viridula decreased as bell age increased from 4 to 18 d from white bloom; damage to 18-d-old bells was negligible. Exposure of 18-d-old bells singly to 5th instars of N, viridula for 7 d reduced bell yield by 59% compared with unexposed bells. Adults of L. lineolaris caused bell injury similar in type to that of 4th instars of N, viridula after confinement of adults singly with an 8-d-old bell for 8 d. However, the much larger 4th instars of N, viridula caused significantly more damage than adults of L. lineolaris, These data should be particularly useful in the development of treatment thresholds for the aforementioned pests in transgenic Bt cotton where insecticide use is limited.