Patterns of Fructose, Glucose, and Sucrose Accumulation in Snap and Dry Bean (Phaseolus vulgaris) Pods

Abstract

Sugars, including fructose, glucose, and sucrose, contribute significantly to the flavor and consumer acceptance of snap beans (Phaseolus vulgaris L.). Little is known regarding differences in sugar content among snap bean and dry bean cultivars and the patterns of sugar accumulation with increasing pod size. Alcohol–soluble sugar concentration of five snap bean cultivars and one dry bean cultivar planted in field trials was assayed throughout pod development over 2 years using high-performance liquid chromatography. Significant differences in sugar accumulation patterns and quantity were observed among cultivars. In general, fructose and glucose content decreased, whereas sucrose increased with increasing pod size in snap beans. In contrast, fructose and glucose amounts increased, whereas sucrose concentration remained unchanged with increasing pod size in the dry bean cultivar. No year-by-genotype interactions were observed for sugar accumulation patterns or sugar amount. Results indicate that sieve size No. 3 (7.34 to 8.33 mm) or No. 4 (8.33 to 9.52 mm) pods are suitable for detecting differences in sugar concentration among genotypes.