GRAIN YIELD OF ISOGENIC CORN HYBRIDS MADE BY USING MALE STERILITY VS. DETASSELLING

Abstract

One factor involved in the decision about the commercial utilization of cytoplasmic male-sterile lines as female parents for developing corn (Zea mays L.) hybrids is that grain yield (F₂ seed) of these hybrids will not differ from that produced by genetically similar hybrids whith female parents that are male-fertile isogenic lines which have to be detasseled. The purpose of this study was to evaluate grain yield and yield components of 12 hybrids: four as control, and eight single cross hybrids in which the male parent was a common restorer line crossed to either four male-sterile lines or their male-fertile isogenic versions but detasseled. A complete block experimental design with four replications, was established in two locations in the State of México, under irrigation, in the Summer growing season of 2002. Significant differences were found for locations and genotypes. Grain yield and yield components of both male-sterile made hybrids and those made by detasseling were statistically similar (P≤0.05) although lower than that of the control hybrids. It is concluded that it is convenient to use these male-sterile lines as female parents to form single cross hybrids, instead of their isogenic fertile counterparts, which need detasseling.