Al. Westedt et al., EVALUATION OF NATURAL AND ENGINEERED RESISTANCE MECHANISMS IN SOLANUM-TUBEROSUM FOR RESISTANCE TO PHTHORIMAEA-OPERCULELLA (LEPIDOPTERA, GELECHIIDAE), Journal of economic entomology, 91(2), 1998, pp. 552-556
Potato tuber moth, Phthorimaea oprrculella Zeller, is a highly destruc
tive pest of cultivated potato, Solanum tuberosum L., and is responsib
le for damage to both leaf and tuber tissues. Host plant resistance is
a central component to developing ten integrated pest management prog
ram to control potato tuber moth. This research tested the efficacy of
a codon-modified CryV-Bacillus thuringiensis (CryV-Bt) gene constitut
ively expressed in potato and the combined effect of CryV-Bt expressio
n with natural host plant resistance mechanisms in potato. 'Lemhi Russ
et' and 2 lines with host plant resistance mechanisms, USDA8380-1 (lea
f leptines) and L235-4 (glandular trichomes), along with the CryV-Bt-t
ransgenic lines of each of these 3 genotypes were examined. Detached l
eaf bioassays were conducted to examine control of potato tuber moth.
Nontransformed Lemhi Russet and L235-4 were susceptible to potato tube
r moth, while 54% potato tuber moth mortality was found when first ins
tar larvae fed on USDA8380-1 leaves. High levels of expression occurre
d in the CryV-Bt transgenic Lines, with up to 96% potato tuber moth mo
rtality. These transgenic lines provide a germplasm base to examine co
mbined insect-resistance mechanisms as a means to achieve durable host
plant resistance.