抗虫棉多茎株型增产机理研究

A Study on the Mechanism of Production Increasing in Anti-insect Cotton with More Stalks

以常规整枝株型为对照,对多茎倒伞株型光合系统质量及根系发育状况进行研究。结果表明:多茎株型有效叶面积增大,叶面积系数最大值为4.55,为常规株型的1.23倍;吐絮期主茎叶片叶绿素含量提高11.8%;盛花期(7月26日),棉田光强分布行间、株间,光强分别提高22.4%和19.1%;棉株倒四叶CO2同化量:初花期为常数株型的1.45倍,终花期(7月19日)为常数株型的1.31倍;地上部干物质生产量为15723kg/hm2为常规株型1.17倍,生殖器官干物重152.1g,为常规株型的1.28倍。多茎株型根干重及根系活力:初花期为常规株型的1.1倍和1.32倍,吐絮期为常规株型的1.39倍和1.77倍;多茎株型根系中可溶性醣含量盛花期为常规株型的1.15倍,结铃期为常规株型的1.30倍。多茎株型建造高质量光合系统,地上与地下相互促进协调发育,既发挥了叶枝对产量的补偿功能,又利用叶枝与主茎水肥的竞争关系减少赘芽滋生,实现高产简化目标。

The study on the photosynthesis System and status of root growth of the cotton with more stems, like inverted umbrella, was carried out in contrast to cotton with normal pruning. The result was as follows：The cotton with more stems, the effective leaf area was 1.23 times that of the normal pruning shape cotton,the maximum LAI up to 4.55 ;the chlorophyll content enhanced by 11.8% over the latter at the boll -opening stage; the illumination density between lines and individual plants respectively increased by 22.4% and 19.1% over that of the normal-shaped of cotton at the peak flowering stage（7/26） ;the assimilation of CO2 in the fourth leaf from the top 1.45 times that of the latter at the early flowering stage, and 1.31 times at the ending flowering stage;the dry matter weight of above ground organs was 15 723 kg/hm^2, 1.17 times that of the normal shaped cotton;both the dry matter weight of root and root activity improved by 1.1 and 1.32 times respectively at the earlier flowering stage while increased by 1.39 and 1.77 times respectively at the boll opening stage compared with the normal - shaped cotton and the soluble sugar concentration in the root enhanced by 1.15 times in contrast to the root of the normal - shaped cotton at the peak flowering stage. And enhanced by 1.30 times at the cotton boll stage. The cotton shape with more stems, could hold high effective photosynthesis system,ensure harmonious growth of the above - ground organs and the root. The cotton plant with more stems could bring vegetative branches into play benefiting the output of the ungrind cotton yield,furthermore, it decreases the number of feeble vegetative branches. All characteristics mentioned above are in favor of high yield.