施氮对高淀粉玉米和普通玉米子粒可溶性糖和淀粉积累的影响

Effects of nitrogen nutrition on sugar and starch accumulation of high starch maize and common maize

采用田间试验、植株生理生化分析和电镜观察等方法,研究了不同氮肥用量对高淀粉玉米吉单535和普通玉米军单8号子粒糖分与淀粉形成的影响。结果表明,在施氮量N 0～200 kg/hm^2之间,两品种玉米子粒淀粉含量随着施氮量的增加而增加,过量施氮则淀粉含量降低。灌浆期吉单535子粒蔗糖、果糖、葡萄糖含量均高于军单8号,适量施氮使子粒灌浆期保持较高的蔗糖、果糖和葡萄糖含量,有利于淀粉合成。高淀粉玉米在成熟期淀粉粒充满了细胞,大小均匀,排列有序;普通玉米的淀粉粒则没有充满细胞,大小不一,排列混乱。适宜施氮下淀粉粒大小较为均匀,淀粉粒之间挤压轻微,而过量施氮下淀粉粒相互挤压成多面体状。

Field experiment, plant physi-biochemical analysis and scanning electro-microscope observation were used to investigate the effects of nitrogen application on sugar and starch formation in high starch maize of Jidan 535, compared with the ordinary maize of Jundan 8. The results indicated that for two maize cultivars, starch concentration in grain increased when N application rate was from 0 to N 200 kg/ha, while decreased when N was over N 200 kg/ha. The concentration of sucrose, fructose and glucose in Jidan 535 was higher than Jundan 8 at grain filling, and higher concentration of sucrose, fructose and glucose in the grain of two maize cultivars was acquired under appropriate N application. Starch granule in the grain of Jidan 535 was full of cell uniformly, and starch granules in the grain of Jundan 8 were arranged in a confusion form. Appropriate N application led starch granule arranged uniformly, but starch granule was squeezed to the status of polyhedron with excessive N application.