Premium
Endosperm Carbohydrate Composition and Kernel Characteristics of shrunken2‐intermediate ( sh2‐i/sh2‐i Su1/Su1 ) and shrunken2‐intermediate–sugary1‐reference ( sh2‐i/sh2‐i su1‐r/su1‐r ) in Sweet Corn
Author(s) -
DodsonSwenson Hallie G.,
Tracy William F.
Publication year - 2015
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci2015.03.0188
Subject(s) - endosperm , fructan , biochemistry , food science , chemistry , fructose
The Shrunken2 ( Sh2 ) gene in maize ( Zea mays L.) codes for ADP‐glucose pyrophosphorylase. Corn homozygous for the shrunken2‐reference ( sh2‐r ) allele does not produce ADP‐glucose pyrophosphorylase, resulting in greatly reduced starch production and increased sugar in the endosperm. The shrunken2‐intermediate ( sh2‐i ) allele produces some enzyme and more starch than sh2‐r . The sugary1‐reference ( su1‐r) allele results in endosperm with large amounts of water‐soluble polysaccharide (WSP), which gives sweet corn good mouth feel. The combination of endosperm WSP and sugar content determines sweet corn quality. We tested the hypothesis that double mutant sh2‐i/sh2‐i su1‐r/su1‐r results in increased amounts of endosperm WSP and sugar than sh2‐r/sh2‐r Su1/Su1 , Sh2‐r/Sh2‐r su1‐r/su1‐r , or sh2‐r/sh2‐r su1‐r/su1‐r . Carbohydrate content was measured in kernels of near‐isogenic inbreds and hybrids of sh2‐i and sh2‐r in Su1 and su1‐r . The lines and hybrids were grown in field trials in 2009 and 2010. Carbohydrate content was determined using enzymatic procedures and quantified with a spectrophotometer. The WSP content in the double mutant sh2‐i su1‐r was greater than in sh2‐r and sh2‐r su1‐r . Sugar content in the double mutant sh2‐i su1‐r was greater than in su1‐r or sh2‐i . The WSP/starch ratio is an important determinant of mouth feel or texture. The sh2‐i/sh2‐i su1‐r/su1‐r hybrids had quality factors that exceed both sh2‐r and su1‐r commercial hybrids.