化学杀雄剂对小麦旗叶光合同化物积累与转运的影响

Effects of CHA on Accumulation and Transportation of Photosynthates in Wheat Flag Leaves

以SN02-3和SN05-3两个小麦品种及其化学杀雄不育系为材料,研究了化学杀雄剂BAU9403对小麦籽粒灌浆过程中旗叶净光合速率(Pn)、库源光合产物积累及转运的影响,并探讨了化学杀雄剂诱导的小麦雄性不育杂交种子籽粒皱瘪不饱满的原因。结果表明,灌浆前期不育系旗叶的Pn比可育系高,但旗叶干物质输出率很低,仅为可育系的41.88%;灌浆后期,不育系旗叶淀粉含量升高,不利于同化物向籽粒转运;不育系籽粒最大体积仅为可育系最大体积(65.40μl/粒)的68.39%,单个籽粒潜在库容要低于可育系。化学杀雄剂导致源器官光合产物输出率低,产物在源端滞留,库器官转化利用能力差,从而使其诱导的小麦雄性不育的杂交种子籽粒皱瘪不饱满。

SN02-3 and SN05-3 and their CHA-male sterile lines were used to study the effects of BAU9403 on the net photosynthetic rate（Pn） and the accumulation and transportation of photosynthates in the flag leaves in the process of wheat grain filling and illustrate the reasons for the thinness of CHA-male sterile hybrid grains.The results showed that the Pn of CHA-male sterile lines was higher than that of their fertile lines and the export rate of dry matter was just 41.88% of that of their fertile lines at the earlier filling stage.At the later filling stage,the starch content in flag leaves of sterile lines increased,which was not good to the transportation of photosynthates to grains;the maximum grain volume of sterile lines was only 69.39% of that of their fertile lines,the potential storage capacity of single grain was lower than that of their fertile lines.In conclusion,CHA could decrease the export rate of photosynthates of source organs and the trans-utilization ability of sink organs,which was the main reason for thinness hybrid grain of CHA-male sterile lines.