|Wilson, R - RETIRED USDA-ARS|
Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 15, 2000
Publication Date: March 16, 2000
Citation: Abel, C.A., Wilson, R.L. 2000. Evaluation of 11 maize populations from peru for mechanisms of resistance to leaf feeding by european corn borer. Journal of Kansas Entomological Society. 72:149-159 Interpretive Summary: The European corn borer is a serious economic pest of maize in the United States and other 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. Our test results indicate that this maize has a negative impact on normal larval development. An interesting discovery was made when resistant freeze-dried whorl leaf material was added to a standard European corn borer diet. The standard diet ingredients either masked the effect of the resistance factor or made up for a nutrient lacking in the Peruvian maize. Further study in this area could help identify the specific factor causing resistance to leaf feeding by European corn borer. The information gained from this research will improve the effective use of this maize as a control method for the European corn borer.
Technical Abstract: Eleven accessions of maize from Peru were previously identified as resistant to leaf feeding by European corn borer, Ostrinia nubilalis (Hubner) (Lepidoptera: Pyralidae). A study was conducted to determine the mechanism of resistance. The weight of larvae fed Peruvian maize leaf material was not significantly different than larvae fed a resistant check, CI31A, indicating antibiosis in the Peruvian maize was at a level equivalent to CI31A. The inbred, CI31A, contained high levels of DIMBOA, thus, having strong nonpreference and antibiosis properties towards leaf feeding by European corn borer. The rate of larvae leaving artificially infested Peruvian maize plants over a five day period was significantly less than CI31A, but, significantly more than a susceptible check, WF9, indicating nonpreference was a possible mechanism of resistance in the Peruvian maize but at a level lower than CI31A. When Peruvian maize whorl leaf material was added to a standard European corn borer rearing diet, the effects of the resistance factor were lost. The standard diet ingredients may have masked the effect of the resistance factor. Another possibility may be that the resistance factor was a deficiency of a vital nutrient needed for normal European corn borer development. This nutrient may have been supplied to the insect when the standard diet ingredients were added to the Peruvian maize leaf material. Further study in this area could help identify the basis of resistance.