不同棉花品种早衰及红叶发生情况调查

Investigation of Premature Senescence and Red Leaf Occurrence in Different Cotton Varieties

【目的】明确不同棉花品种早衰发生情况及红叶的发生原因,为生产上棉花品种的合理布局提供依据。【方法】调查棉花早衰原因,对采集样品进行理化性质分析。【结果】调查发现,棉花早衰的发生情况比较普遍,早衰对产量造成的损失达40%以上;引起早衰主要原因是品种抗病性差以及肥水不足;气温的急剧变化是造成棉花红叶的诱因;叶片检测发现正常棉叶中全氮、全磷、全钾含量比红叶中增加37.6%、20%和9.7%,微量元素差距不明显;土样检测发现正常棉叶田所采土样中全氮、全钾含量比红叶田土样减少34.7%和13.9%。【结论】抗病性差的品种容易发生病理性早衰,肥水不足容易造成生理性早衰;棉花红叶是由于气温的急剧降低导致棉花根部受激,吸收养分能力降低,氮磷钾含量降低,影响叶片同化效率所致。

[Objective]To ascertain the causes of premature senescence and red leaf occurrence in different cotton varieties, and provide basis for reasonable disposal of varieties for cotton production. [ Method ] Cause of premature senescence was investigated, the physical - chymic character of the sample was analyzed. [ Result] Cotton premature senescence is prevalent, and has a yield reduce of over 40 percent; disease resistance deficiency and insufficiency of fertilizer and water are the major causes;the occurrence of red leaf is mainly caused by the sudden change of weather and temperature; content of azote, phosphorus and kalium in the soil of normal leaf are respectively 37.6%, 20% and 9.7 % more than in the red leaf, and there is no obvious difference in microelement content. Content of azote and kalium in the soil of normal field is 34.7% and 13.9% less than in red leaf field. [Conclusion] Pathological premature senescence is easily occurred in the disease resistance deficiency varieties, physiological premature senescence is easily seen in the fields which lack fertilizer and water. Cause of red leaf ： cotton root is stimulated by the rapid temperature decline, and its nutrient absorption capability is reduced, the content of azote, phosphorus and kalium declines, which influences the assimilation efficiency of lamina.