Genetic Modifications of Sweet Corn Quality1

Abstract

Abstract Carbohydrate analyses were made at harvest and after 7 days of postharvest storage at 65°F on sweet corn hybrid cultivars with endosperm mutant genotypes ae wx, ae du wx, and sh2 and of standard sweet corn (su1). Cultivars with the mutant genotypes contained from 1.5 to 2.0 times as much total sugar at harvest as the standard. They also lost more total sugar during the post-harvest period. Still, the hybrids with ae du wx and sh2 genotypes contained significantly more sugars than the standard after the 7-day storage treatment. The mutant cultivars were low in water soluble polysaccharides but relatively high in starch. All cultivars had approximately the same amount of total carbohydrate. Moisture loss from the kernels during the storage period was significantly less in the mutant cultivars. Therefore, they maintained their fresh appearance longer, and they were slower than standard sweet corn to show kernel denting. Taste tests indicated a preference for the sweetness of the ae wx and ae du wx genotypes over the standard cultivars Golden Security and ‘Iobelle’ (Florida 104), but they were rated below the standards for pericarp toughness. These studies indicated that, with further refinement of certain horticultural and quality characteristics, the ae wx, ae du wx, and sh2 endosperm mutant genotypes have a definite potential for improving the initial quality and the ability for maintaining good quality during normal post-harvest handling of fresh sweet corn.