春小麦灌浆期功能叶^(14)C同化物源-库调控

Source sink Regulation of Assimilates from Functional Leaves During Grain Filling Stage in Spring Wheat

利用１４ＣＯ２示踪研究春小麦灌浆期旗叶同化物在源库间运转与分配。结果表明，上午同化产物在同化后４ｈ的输出占２４ｈ输出的７０％；下午同化的只有３１％，基本上是在同化后１０ｈ输出。不过两者同化后２４ｈ总输出基本一致，均在６７％左右。同化的产物输出有“排队现象”，即先同化先输出。叶片中１４Ｃ可溶性糖（１４Ｃ蔗糖）占１４Ｃ同化物的比例始终较高，同化后１０ｈ平均分别为６４．３％（１４Ｃ蔗糖为４５．７％）和６６．９％（１４Ｃ蔗糖为５２．６％）。籽粒中１４Ｃ同化物的积累有先同化先进入现象。还发现１４Ｃ可溶性糖（含１４Ｃ蔗糖）在籽粒中相对含量始终很高，这表明其转化成淀粉需要一定时间。

Translocation and distribution of flag leaf assimilates between source and sink was detected by trace atom 14 C during grain filling stage of spring wheat.The results suggested that the output rate of assimilation product after 4 hours in the morning made up 70% of that after 24 hours,in the afternoon the assimilation product only made up 31% which was basically exported 10 hours after assimilating. The total output rate after 24 hours showed no difference between morning and afternoon(67%).There was a trend that first assimilating for first output. 14 C soluble sugur( 14 C sucrose)was aways higher in the proportion of 14 C assimilates.It was also found that first assimilating for first accumulation in grains and higher content of 14 C soluble sugur ( 14 C sucrose)indicated that a certain time was required for convertion of sugur into starch.