留营养枝对棉株同化物生产、运转、分配及产量的影响

Effect of remaining monopodial branches on the ^(14)C-assimilation,partitioning of ^(14)C assimilates and lint yield of the cotton plant

运用 14 C示踪技术研究了留营养枝棉株 14 C同化物生产运转分配规律。结果表明 :留营养枝与否对全株 14 C总同化量基本没有影响 ,但留营养枝棉株果枝叶的相对光合强度 (以放射性比强度表示 )降低 ;主茎叶、果枝叶的 14 C同化量显著降低 ;营养枝叶具有较高的光合作用强度和向外输送 14 C同化物的转运速率 ,在 14 C同化物生产运转分配中占有很重要的地位。留营养枝棉株 14 C同化物在花铃期向主茎和果枝的分配极显著降低 ,从而导致主茎和果枝发育较差、结铃数量减少 ,但营养枝可间接着生蕾铃 ,在产量形成中占有一定比重。因此 ,留营养枝与否对皮棉产量无显著影响。

Using 14 C tracing technique,the 14 C assimilation and partitioning of 14 C assimilates of the cotton plant with monopodial branches were studied.The results were as follows:the 14 C assimilation of the leaves on main stem and fruiting branches of cotton plant with monopodial branches were reduced significantly.However,there was a small influence on total 14 C assimilation of plant,because the leaves on monopodial branches have higher 14 C assimilation.The distribution of 14 C assimilates in the plant organs 3 days after labelling indicated the remaining monopodial branches could decrease the translocation of 14 C assimilates into main stem and fruiting branches at flowering and fruiting stage,which was harmful to the growth and development of main stem and fruiting branches,and reduced the number of bolls on fruiting branches.But there was no remarkable effect on the number of bolls per hectare,boll weight,lint percent and lint yield,because monopodial branches have some bolls.