VARIATION IN SWEET CORN KERNEL CHARACTERISTICS ASSOCIATED WITH STAND ESTABLISHMENT AND EATING QUALITY

A better understanding of the relationships between kernel characteris tics associated with eating quality and stand establishment could be h elpful in selection of superior genotypes by the sweet corn industry. A set of sweet corn (Zea mays L.) inbred lines with different endosper m mutations (sul, sul sel and sh2) were evaluated for field emergence and seedling growth rate at two locations over two years. Kernel chara cteristics associated with eating quality (kernel moisture concentrati on, kernel tenderness, sugars, phytoglycogen and dimethyl sulfide (DMS ) concentrations were determined for the same inbreds by laboratory an alysis from ears harvested at 18 and 22 days after pollination (DAP). Amounts of sugars, phytoglycogen and starch were also measured in matu re dry kernel samples of the same inbreds. Extensive genetic variabili ty was found among endosperm mutations and among genetic backgrounds w ithin the different endosperm groups for most of the characteristics u nder study. Most of the kernel attributes associated with eating quali ty were uncorrelated indicating that selection to improve specific eat ing quality characteristics can be conducted simultaneously. A negativ e correlation between field emergence and sugar concentrations in imma ture kernels suggests that in breeding programs designed to develop ge rmplasm with improved germination and stand establishment, concurrent attention must be given to the fresh quality of the harvested product. This information is of value to breeders and commercial growers for s election of sh2 and sulsel lines with superior field emergence and eat ing quality.