Performance of Maize Inbred Line B86 in Hybrid Combinations: Resistance to First- and Second-generation European Corn Borers (Lepidoptera: Pyralidae)

Abstract

Inbred line B86 was crossed with nine dent maize, Zea mays L., inbred lines. The nine lines, plus B86 and a check inbred line, and the nine single crosses, plus a single-cross check, were planted in a modified randomized block design during 4 years, with six replications each year. First-generation European corn borer (ECB), Ostrinia nubilalis Hübner, test plots were separate from the second-generation ECB test plots (two hills of three plants for each plot in each experiment). Plants in the first-generation tests were infested during the midwhorl stage of plant development, whereas plants in the second-generation tests were infested during an thesis. Plants in each test were infested with 12 egg masses (300 eggs) per plant in six applications of two masses, spaced 1 day apart. Leaf feeding damage in the first-generation tests and sheath-collar feeding damage and stalk damage in the second-generation tests were determined. B86 was resistant to first- and second-generation ECB; in combination with several susceptible inbred lines, B86 resistance showed variable levels of partial dominance for resistance to leaf feeding by first-generation ECB and for sheath-collar and stalk feeding resistance by second-generation ECB.