施氮时期对花后高温胁迫下春小麦淀粉形成的影响

Effects of Nitrogen Time on Starch Formation of Spring Wheat at High Temperature after Anthesis

【目的】春小麦灌浆期频繁遭受高温胁迫,导致小麦产量降低、品质变劣。研究缓减高温危害的栽培措施,对春小麦高产稳产优质具有重要意义。【方法】本研究采用裂区试验设计,以宁夏灌区主栽品种宁春4号为供试材料,研究定氮条件下不同追肥时期对高温胁迫下春小麦淀粉形成的影响。【结果】高温胁迫导致籽粒中总淀粉含量和淀粉关键酶活性下降,而拔节期、孕穗期追施氮肥可以缓减高温危害。孕穗期处理下,高温与常温相较总淀粉含量减少7.18%。在常温条件下,孕穗期较分蘖期追施氮肥,总淀粉含量、ADPG-PPase、SBE、SSS分别增加24.6%、32.2%、39.7%、37.7%。【结论】方差分析表明,温度与施氮时期对淀粉含量及淀粉关键酶活性有显著影响,其中,拔节期、孕穗期追施氮肥可以有效缓减高温对籽粒淀粉含量、淀粉关键酶及产量的影响,说明适当的氮肥后移可以有效缓解高温对春小麦品质及产量的影响。

[ Objective] The spring wheat that was frequently exposed on high temperature stress during the filling stage resulted in that the yield of wheat yield was decreased and the quality was deteriorated. So the study of the measures to reduce the harm of high temperature was very important for the high yield and stable quality of spring wheat. [ Method ] In the present experiment, Ningchun 4 （ Ningxia inigation dis- trict main varieties） was used as tested materials, and the split plots were designed to study the effects, and under high temperature stress, the effects of different topdressing nitrogen fertilizer stage on starch formtion were studied. [ Result] Under high temperature stress the con- tent of total starch and the activity of key enzymes in starch decreased, while at the jointing stage and booting stage the treatment of topdress- ing nitrogen fertilizer could reduce the harm of high temperature. At the booting stage under high temperature stress the total starch content decreased 7.18 % compared to normal temperature. Under normal temperature, comparing booting stage to tillering stage treatment, the content of total starch, the activity of ADPG-PPase, SBE and SSS increased by 24.6 %, 32.2 %, 39.7 %, 37.7 %, respectively. [ Con- clusion ] The variance analysis showed that the effects of temperature and nitrogen application on starch content and the activity of starch en- zyme were significant, of which the topdressing nitrogen fertilizer at jointing stage and booting stage could effectively reduce the effect of high temperature on starch content, starch enzyme and yield. The results indicated that the suitable topdressing nitrogen fertilizer period could ef- fectively alleviate the effect of high temperature on the quality and yield of spring wheat.