氮营养对秋马铃薯块茎发育中淀粉积累的影响

以高、低两类淀粉型品种为试验材料，研究在秋季栽植条件下不同氮营养水平对块茎淀粉积累特性的影响，为秋马铃薯的优质栽培提供依据。结果表明：①块茎发育中各施氮量下块茎总淀粉、支链淀粉和直链淀粉的含量呈“S”曲线变化，符合 Logistic方程 Y=K/（1＋ae-bT），但不同施氮量对各淀粉积累强度，达到最大积累强度出现的时间存在差异，品种之间的影响也不完全一致。②高淀粉品种 XS-1，直链淀粉的最大积累强度在中等施肥水平较低，低、高施肥水平较高，支链淀粉、总淀粉随着施氮量的增加呈先升后降的变化趋势，低淀粉品种 XS-2,随着施氮量的增加，直链淀粉的最大积累强度呈下降，支链淀粉呈不断上升趋势，总淀粉呈先上升后又下降的变化趋势，达到最大积累强度的时间直链淀粉、总淀粉呈先升高后下降，支链淀粉一直下降的的变化趋势。

The influence of Nitrogen Nutrition on Starch Accumulation in the Process of Tuber Development in Autumn Solanum tuberosum L.

Taking two varieties, high and low starch content respectively, as tested materials, experiments were conducted to study the effects of nitrogen fertilizer in different levels on tuber starch accumulation characteristics under autumn planting condition, and thus to provide technical support in optimized planting techniques of autumn potato. The results showed that during tuber development the changes in concentrations of total starch, amylopectin and amylose were ＂S＂ shaped curve un-der different nitrogen fertilizer treatments, in line with the Logistic equation Y=K/（1＋ae-bT）, but both starch accumulation intensity and the time reaching to maximum ac-cumulation intensity were not exactly the same in different nitrogen fertilizer levels so is it with different varieties. Furthermore, high starch concentration variety ‘XS-1’, the largest accumulation of strength of amylase was the lower in the middle fertil-ization and higher in low and high fertilization treatments. The contents of amy-lopectin, total starch were first increasing and then dropping with the amount of ni-trogen increasing. To low starch concentration variety ‘XS-2’, with nitrogen fertilizer content increase, the largest accumulation of strength was reducing in amylose, but was rising in amylopectin and changed from rising to fal ing in total starch. The time reaching to maximum accumulation strength in amylose and total starch changed from increasing to decreasing and amylopectin kept declining.