HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Thome, C. R. Articles by Mihm, J. A. Search for Related Content PubMed Articles by Thome, C. R. Articles by Mihm, J. A. Agricola Articles by Thome, C. R. Articles by Mihm, J. A.

Yield Reduction in a Maize Diallel under Infestation with Southwestern Corn Borer

Calgene Fresh, Inc., 1910 Fifth St., Davis, CA 95616
Dep. of Plant Breeding and Biometry, Cornell Univ., 252 Emerson Hall, Ithaca, NY 14853-1902
CIMMYT Maize Program, Lisboa 27, Apdo. Postal 6-641, 06600 Mexico D. F., Mexico

^* Corresponding author (thome{at}calgene.com).

The southwestern corn borer (SWCB), Diatraea grandiosella Dyar, is an important pest of maize (Zea mays L.) in some parts of the Americas. Germplasm with resistance to leaf feeding by this insect pest was developed at the International Maize and Wheat Improvement Center (CIMMYT) in Mexico, but little is known about the inheritance of resistance or combining ability for yield in this germplasm. A 10-parent maize diallel cross of eight CIMMYT inbreds and two susceptible public inbreds was evaluated for leaf feeding resistance to SWCB and for yield under both infestation and protection from SWCB. Trials were grown at Tlaltizapdn, Morelos, Mexico, in the dry season of 1989-1990 and rainy season of 1990. General combining ability (GCA) was the most important source of variation among F₁S for leaf feeding damage rating and for yield. The relationship between leaf feeding damage and yield reduction was linear but variable. The most insect resistant lines in this study were selected under infestation with larvae of several species of stalk boring insects but were never directly selected for combining ability for yield. These lines improved GCA for yield only under heavy SWCB infestation. An inbred that was susceptible to leaf feeding had better combining ability for yield than all other lines in the study in both seasons under infestation and protection. The results of this study demonstrate that selecting directly for combining ability for yield across environments may be more useful than selecting directly for insect resistance without selecting for yield.

Received for publication August 12, 1993.