Submitted to: Corn and Sorghum Seed Research Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: October 5, 1998
Publication Date: N/A
Interpretive Summary: The European corn borer is a serious economic pest of maize in the United States and other temperate regions of the world. Because of the limitations of insecticides for control, the development of resistant maize hybrids has been one of the most efficient methods of control. Eleven populations of Peruvian maize were found to have a unique source of resistance to European corn borer. A plant breeding program was designed to successfully move the unique trait into two agronomically superior inbred lines. Experimental lines were developed that have yield potential and the unique resistance trait. The resistance trait impedes European corn borer development. Fifteen experimental lines of maize from the plant breeding program were found to be resistant to the corn earworm, fall armyworm, and the sugarcane borer. This research will impact maize agriculture in the following ways: 1) it will give maize growers another control option for European corn borer, 2) it will give plant breeders an opportunity to combine this new trait with existing traits to improve the stability of maize resistance to the European corn borer, and, 3) it may provide traits needed for the development of maize hybrids resistant to more than one insect pest.
Technical Abstract: Eleven accessions of Peruvian maize were evaluated for mechanisms of resistance to leaf feeding by European corn borer, Ostrinia nubilalis (Hubner). Antibiosis was identified as the primary mechanism of leaf feeding resistance. The 11 Peruvian maize accessions were used as donor parents in a plant breeding program designed to introgress the resistance trait into two elite inbred lines. Resistance was recovered in the F1 indicating dominant genetic control. Genetic control of resistance to leaf feeding is independent of that for sheath and collar feeding. Some testcrosses had a mean yield not significantly different than the highest yielding commercial check. BC3 S1 experimental lines were developed which have yield potential plus the unique source of resistance to the European corn borer. Fifteen experimental lines of maize derived from the backcross breeding program were evaluated for resistance to the European corn borer, corn earworm [Helicoverpa zea (Boddie)], fall armyworm, [Spodoptera frugiperda (J. E. Smith)], and sugarcane borer, [Diatraea saccharalis (Fabricius)]. A few lines had varying levels of resistance to all of the insects tested. Experimental line 107-8-7 was identified as being resistant to corn earworm while maintaining low levels of maysin.