摘要
试验研究小麦籽粒生长期热效应结果表明，小麦开花后热胁迫降低同化源供应，影响库性能，进而影响产量和品质。不同热胁迫形式和不同热胁迫时期对籽粒生长的影响不同。中等高温（25～32℃）下籽粒灌浆持续期缩短，籽粒重下降；极端高温（33～40℃）下籽粒灌浆速率的降低和籽粒灌浆持续期的缩短相伴发生，最终籽粒重明显降低。非叶器官具有较高的磷酸烯醇式丙酮酸羧化酶（PEPC）等Cd途径酶活性，其光合耐热性高于叶片。籽粒可溶性淀粉合成酶（SSS）对高温胁迫极为敏感，该酶活性的降低是热胁迫下粒重下降的重要机制。发挥非叶器官Cd光合活性，增强籽粒SSS耐热性是热胁迫下稳定粒重的重要途径。
The effect of heat stress in the grain-growing period of wheat was studied. The results show that post-anthesis high temperature influences the grain yield and the quality of wheat by altering the source and sink functions. The effects of high temperature on the grain growth depend on the timing of heat exposure and the degree of heat stress. Under the moderately high temperature （25- 32℃ ）, the grain mass primarily reduces by reducing the duration of grain filling. Under the very high temperature （33-40℃）,the filling rate decreases and the sustainable period of filling shortens, finally the grain weight decreases significantly. Soluble starch synthase（SSS） is very sensitive to high temperature. It is shown that the reduction in the rate of grain growth at high temperature is mainly due to the reduced activity of SSS. Compared with leaf blades,the non-leaf green organs in wheat possess higher levels of C4 photosynthetic enzymes and have greater heat tolerance in photosynthesis. Therefore, in order to improve the grain yield of wheat under high temperature conditions, it is important to strengthen the role of non-leaf organs in photosynthetic source and increase the activity of SSS in grain sink.
出处
《中国生态农业学报》
CAS
CSCD
2006年第3期8-11,共4页
Chinese Journal of Eco-Agriculture
基金
国家自然科学基金项目(30270780)资助
关键词
小麦
籽粒生长
热效应
品质
Wheat, Grain growth, Effect of heat, stress, Quality
