Stalk Strength and Sugar Content of Different Dual-Purpose Sorghum Lines

摘要

Dual-purpose bioenergy crops, in which reduced carbon is harvested from multiple sources, are efficient feedstocks because carbon accumulation in any one organ is usually sink-limited. In other words, carbon yield from the vegetative stalk can usuallybe increased without sacrificing starch yield from the grain. In December 2012, sorghum was approved by EPA as an advanced bioenergy feedstock as it is highly tolerant to drought and requires lower inputs than maize. However, it is susceptible to lodging which reduces grain yields significantly. Stalk moisture and sugar content affect harvest, transport, and storage strategies. Therefore, identifying sorghum varieties with stronger stalk strength can prevent lodging damage and differentiating the hybrids with higher sugar content can increase potential biofuel yield. In this study, rind penetrometerresistance measurements of stalk strength and sugar content of the leaves and the stalks of 40 dwarf grain sorghum inbreds and 15 photoperiod sensitive sorghum inbreds were measured. These measurements were calibrated against the Fourier transform near infrared (FT-NIR) spectra of ground sorghum stalks and leaves to cluster inbreds using principal components analysis (PCA). Results showed dwarf grain sorghum contained 0.1-6.9% glucose in stalks, 0.3-3% glucose in leaves, 0-15% sucrose in stalks, 0-6.5%sucrose in leaves, and stalks strengths were ranged from 2.43-7.72 kg; photoperiod sensitive sorghum contained 0.6-12% glucose in stalks, 0.3-1.7% glucose in leaves, 0.3-17% sucrose in stalks, 0-3.1% sucrose in leaves, and stalks strengths were ranged from 2.43-7.72 kg. PCA results effectively clustered two varieties, fractions from leaves and stalks, and differentiated the sugar contents in stalks.