论文部分内容阅读
为了解新疆棉花栽培中打顶措施与棉花早衰间的关系,在盆栽条件下研究了低氮(150mg·kg-1)和高氮(500mg·kg-1)条件下,不打顶、打顶和打顶后涂抹生长素处理对棉花内源激素含量的影响。结果表明,低氮水平下,棉花打顶后功能叶片细胞分裂素(CTK)和可溶性蛋白质含量降低,而脱落酸(ABA)和丙二醛(MDA)含量增加;打顶后涂抹生长素处理CTK和可溶性蛋白质含量均比打顶和不打顶处理高,而ABA含量低于打顶处理,但仍比不打顶处理高。打顶处理ABA/CTK的比值均高于不打顶处理,而打顶后涂抹外源生长素又使ABA/CTK比打顶处理有所降低。叶片MDA含量对不同打顶处理的响应与激素比值的响应表现出相似趋势。高氮水平下,打顶或打顶后涂抹生长素处理的ABA含量高于不打顶处理。打顶处理在低氮条件下叶绿素含量均高于高氮条件。试验结果表明,高氮处理的施氮量超过了棉花植株生长需要,出现了ABA累积,对植株生长产生抑制。低氮条件下,打顶提高了棉花叶ABA的绝对含量、ABA/CTK和MDA含量,表明打顶促进了棉花衰老,而打顶后涂抹生长素在一定程度可延缓衰老进程。
In order to understand the relationship between topping practices and cotton premature senescence in Xinjiang cotton cultivation, under the condition of low nitrogen (150mg · kg-1) and high nitrogen (500mg · kg-1) And the effects of top-dressing with auxin on the content of endogenous hormones in cotton. The results showed that the content of cytokinin (CTK) and soluble protein in functional leaves of cotton decreased while the content of ABA and MDA increased in the low nitrogen level, and CTK And soluble protein content were higher than topping and not topping treatment, while ABA content was lower than topping treatment, but still higher than the non-topping treatment. The ratio of ABA / CTK to topping treatment was higher than that of the non-topping treatment, while ABA / CTK reduced topping treatment after topping application of exogenous auxin. The response of leaf MDA content to different topping treatments showed a similar tendency with the hormone ratio. Under high nitrogen level, the content of ABA in topsoil or topping with apigenin treatment was higher than that in top treatment. The chlorophyll content of the topping treatment under high nitrogen was higher than that of high nitrogen. The results showed that the nitrogen application rate of high nitrogen treatment exceeded the requirement of cotton plant growth, and the emergence of ABA accumulation inhibited plant growth. Under low nitrogen conditions, topping increased the absolute content of ABA, ABA / CTK and MDA in cotton leaves, indicating that topping promoted the cotton senescence, while the application of auxin delayed the aging process to a certain extent.