双波长分光光度法测定木薯块根淀粉含量的动态变化

Time Course of Starch Content in Cassava Root Tuber Determined by Dual-Wavelength Spectrophotometry

以双波长分光光度法测定SC201、SC205、GR891和GR911共4个木薯品种生育期块根中直链淀粉与支链淀粉含量的动态变化。结果表明,4个木薯品种块根直链淀粉的含量是随生育期的延长而逐渐增加的,而支链淀粉的含量却缓慢下降,支链淀粉/直链淀粉的比例呈现下降趋势,到12月份4个品种的这一比例已接近相同;以鲜重计的总淀粉含量,4个品种均呈逐渐增加的趋势;而以干重计的总淀粉含量的变化则4个品种表现不一致。研究初步揭示了木薯块根直链淀粉、支链淀粉和总淀粉含量的积累规律。

Abstract The time course of amylase and amylopectin content in root tuber of four cassava cuhivars, SC201, SC205, GR891 and GR911 ,were determined by dual- wavelength spectrophotometry. The results showed that ：the am- ylose content of cassava root tuber of four cultivars gradually increase in the time course, however the amylopectin de-creased along with the growth period, and the ratios of amylopectin/amylose of four cuhivars were decreased continu- ously,by December, their ratios were very close to 1： 1. The starch content by fresh weight in four cultivars also in- creased,while the starch content by dry weight in four cuhivars were different. This research revealed the aecumulation rule of amylose, amylopectin and total starch of cassava root tuber.