Open AccessLARVICIDAL ACTIVITY OF STRAINS OF BACILLUS THURINGIENSIS FOR HELICOVERPA ARMIGERA (HÜBNER) AND HELICOVERPA PUNCTIGERA WALLENGREN (LEPIDOPTERA: NOCTUIDAE) ESTIMATED USING A DROPLET‐FEEDING METHOD
Author(s) -
Teakle R. E.,
Caon G.,
Grimshaw J. F.,
Byrne V. S.
Publication year - 1992
Publication title -
australian journal of entomology
Language(s) - English
Resource type - Journals
eISSN - 1440-6055
pISSN - 1326-6756
DOI - 10.1111/j.1440-6055.1992.tb00486.x
Subject(s) - helicoverpa armigera , potency , biology , bacillus thuringiensis , subspecies , helicoverpa , lepidoptera genitalia , noctuidae , larva , veterinary medicine , serotype , microbiology and biotechnology , botany , bacteria , zoology , biochemistry , medicine , genetics , in vitro
The potencies of 10 strains (seven subspecies) of Bacillus thuringiensis for Helicoverpa armigera and H. punctigera were compared using a droplet‐feeding method. Larvae were attracted to petri dishes for dosing using a light‐proof box, and imbibed the bacteria in droplets sprayed onto the dishes. The strains displayed a 300‐fold difference in potency for H. armigera and 750‐fold difference for H. punctigera. Two strains were equal to the commercial strain (subspecies kurstaki , serotype 3a3b) in potency against H. armigera , namely subspecies kenyae , serotype 4a4c and aizawai , serotype 7; and one, kenyae , serotype 4a4c, was also similar to the commercial strain against H. punctigera. The strains ranked similarly in potency against H. armigera and H. punctigera , suggesting that screening for potency against both Helicoverpa spp. can be accomplished by testing against only one of the species.