EVALUATION OF THE UNITED-STATES-NATIONAL-GERMPLASM-SYSTEM POPCORN COLLECTION FOR RESISTANCE TO CORN-EARWORM (LEPIDOPTERA, NOCTUIDAE) AND EUROPEAN CORN-BORER (LEPIDOPTERA, PYRALIDAE)
Rl. Wilson et al., EVALUATION OF THE UNITED-STATES-NATIONAL-GERMPLASM-SYSTEM POPCORN COLLECTION FOR RESISTANCE TO CORN-EARWORM (LEPIDOPTERA, NOCTUIDAE) AND EUROPEAN CORN-BORER (LEPIDOPTERA, PYRALIDAE), Journal of economic entomology, 86(3), 1993, pp. 952-956
The U.S. National Germplasm System's active collection of popcorn, Zea
mays L., is maintained at the North Central Regional Plant Introducti
on Station at Ames, IA. From 1983 to 1989 and from 1982 to 1990, 299 a
ccessions of this collection were evaluated for sources of resistance
to com earworm, Helicoverpa zea (Boddie), and European com borer, Ostr
inia nubilalis (Hubner), respectively. During 1990, 32 accessions prev
iously rated as resistant to com earworm, and in 1991, 39 accessions p
reviously rated as resistant to leaf feeding by first-generation Europ
ean com borer were retested for resistance. Coin earworm larval weight
s, when grown on silks from 21 of the 32 accessions retested for resis
tance, were not significantly different from the weights of larvae gro
wn on the resistant control but were significantly smaller than larvae
grown on the susceptible control. Fourteen of the 39 accessions retes
ted for first-generation feeding resistance to European corn borer ret
ained their resistance. Genetic studies will be necessary to determine
if these new sources of resistance are governed by genes different fr
om those in previously identified sources.