SHRUNKEN2 SWEET CORN YIELD AND THE CHEMICAL-COMPONENTS OF QUALITY

Extensive variability was found among 24 currently available commercia l sh2 hybrids of sweet corn (Zea mays L.) for yield and yield componen ts, and for the chemical components of eating quality. The primary sou rce of variation was explained by genotypic differences, with the envi ronmental effects due to planting locations having a minor influence. Kernel sugar concentrations, however, had a highly significant level o f genotype by environment interaction. The extensive genotypic variabi lity among the sh2 hybrids indicated that allelic variation at other l oci is profoundly influencing sucrose and total sugar levels in freshl y harvested sweet corn. In each case, the kernel chemical components o f quality decreased from 20 to 29 days after pollination (DAP). Mean p erformance of sh2 hybrids for yield, yield components, and kernel qual ity parameters was in all cases equal or better than the hybrids homoz ygous for the sul endosperm mutation. In addition, there were no stron g negative relationships between yield and some of the important chemi cal components of kernel quality, suggesting that it may be feasible t o develop superior sh2 hybrids with acceptable yield potential and imp roved eating quality targeted for the different sweet corn markets.