Maize starch fine structures affected by ear developmental temperature
Journal
Carbohydrate Research
Journal Volume
282
Journal Issue
1
Pages
157-170
Date Issued
1996
Author(s)
Abstract
Growing temperature is known to affect the grain yield and quality of maize. Two genetically unrelated normal dent maize inbreds, IC163 and IC192, with different heterotic backgrounds were grown in a greenhouse with the ears wrapped in temperature control devices set at 25 and 35¢XC during the grain-filling period. Grain yield, kernel weight, and kernel density were less for ears at 35¢XC than for those at 25¢XC. The extent of the loss, however, varied with the variety: 13.1 and 37.9% kernel weight loss and 8.47 and 10.08% density loss for IC163 and IC192, respectively. The starch granular shape of IC163 became more oval-shaped, but there was no shape change for IC192. As developmental temperature increased, starch granule size decreased and gelatinization temperature increased. With increasing developmental temperature, the true amylose content of IC163, determined by iodine affinity, decreased 2.39% and that for IC192 decreased 2.20%; amylose molecular size of both varieties also decreased. Size exclusion chromatography and high-performance anion-exchange chromatography revealed an increased medium branch-chain fraction and decreased long and short branch-chain fractions for IC163 amylopectin, whereas IC192 amylopectin had increased long and medium branch-chain fractions and a decreased short branch-chain fraction, when the ear developed at 35¢XC.
Subjects
amylopectin
amylose
maize
starch
Type
journal article