论文部分内容阅读
同化物源端装入过程包括源(叶等)光合产物的形成、转化、积累和输出;同化物库端卸出过程包括来自源的光合产物在库端(籽粒等)的输入、转化及积累。在小麦籽粒灌浆期,同化物源端装入快慢直接关系到同化物的库端卸出快慢,二者又与源叶光合产物在源-库之间的分配直接相关,如果同化物在库端卸出快,就有利于更多的光合产物向籽粒运转,转化为淀粉而贮存起来,故而它们与作物产量高低密切相关。我们以前的研究表明:在籽粒灌浆期,春小麦旗叶同化物的源端装入和库端卸出表现为昼夜周期变化规律,即旗叶同化物的运转周期为24h,在其同化后24h内输出70％左右,大部分在库端卸出。但上述试验为期1天,其结果能否在小麦整个灌浆期成立,还有待于进一步证实。由于小麦籽粒灌浆速度表现为“慢—快—慢”的特性,那么在小麦籽粒灌浆初期、中期和后期,旗叶同化物的源端装入和库端卸出是否都表现昼夜周期变化规律呢?为此,我们以冬小麦为试验材料进行研究。
The assimilate source loading process includes the formation, transformation, accumulation and export of photosynthetic products of the source (leaf, etc.); the unloading process of the assimilate reservoir includes the input, transformation and accumulation of photosynthate from the source . At the grain filling stage of wheat, the speed of the assimilate loading at the source end is directly related to the speed at which the ends of the assimilates are unloaded, both of which are directly related to the distribution of source photosynthate between the source and the sink. Unloading fast, it will help more photosynthetic products to the grain, converted to starch and stored up, so they are closely related with the crop yield. Our previous studies showed that at the grain filling stage, the source loading and the shedding of spring wheat flag leaf metabolites showed a diurnal cycle variation pattern, that is, the operating cycle of flag leaf assimilate was 24 h and within 24 h after its assimilation Output about 70%, most of the discharge in the library. However, the above test for a period of one day, the results can be established throughout the grain filling wheat, remains to be further confirmed. Since the grain filling rate of wheat is characterized by “slow-fast-slow”, whether the source-end loading and the unloading of flag-leaf assimilates show the circadian variation during the early, middle and late grain filling stages of wheat For this reason, we use winter wheat as the experimental material.