Shrunken2 Sweet Corn Yield and the Chemical Components of Quality

Extensive variability was found among 24 currently available commercial sh2 hybrids of sweet corn (Zea mays L.) for yield and yield components, and for the chemical components of eating quality. The primary source of variation was explained by genotypic differences, with the environmental effects due to planting locations having a minor influence. Kernel sugar concentrations, however, had a highly significant level of genotype by environment interaction. The extensive genotypic variability among the sh2 hybrids indicated that allelic variation at other loci is profoundly influencing sucrose and total sugar levels in freshly harvested sweet corn. In each case, the kernel chemical components of quality decreased from 20 to 29 days after pollination (DAP). Mean performance of sh2 hybrids for yield, yield components, and kernel quality parameters was in all cases equal or better than the hybrids homozygous for the su1 endosperm mutation. In addition, there were no strong negative relationships between yield and some of the important chemical components of kernel quality, suggesting that it may be feasible to develop superior sh2 hybrids with acceptable yield potential and improved eating quality targeted for the different sweet corn markets.