Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: 1/14/1999
Publication Date: N/A
Technical Abstract: Sweet corn (Zea mays L.) kernels are carbohydrate sinks, and sugars found in kernels must be translocated from a source. Stalk tissues can act both as a source and a sink as sweet corn plants age. Quantity and types of sugars present in various sweet corn tissues during plant development are not well documented. Concentrations of fructose, glucose, sucrose and their total were determined in the ninth stalk internodes (I9) from the 12 leaf stage (V12) to fresh-market maturity (R3) in sweet corn cultivars carrying either the su1se1, su1 or sh2 endosperm genotype. Developing ears were sampled at tassel emergence (VN) and silking (R1). Kernels and cob tissue were sampled separately at blister stage (R2) and R3. Correlation analysis was performed on concentrations of sugars at all developmental stages. In I9, from V12 to R3, levels of fructose and glucose declined and sucrose increased. In developing ears, concentrations of fructose and glucose increased from VN to R1. Concentrations of sugars in cobs in all cultivars were generally the same at R2 and R3. In kernels from R2 to R3 in the su1se1 cultivar glucose decreased while the other sugars were unchanged; in the su1 cultivar fructose decreased while levels of the other sugars stayed the same; and in the sh2 cultivar fructose decreased, glucose was unchanged and sucrose increased. Correlation analysis suggests that the cultivars have different patterns of sugar translocation to kernels. The pattern of movement of sugars was most complex in the su1se1 cultivar than in the su1 cultivar which was more complex in sh2. Knowing how sugar content changes in the plant may be used to predict sugar content in kernels.