钾用量与灌溉量对不同土层钾素及烟叶钾含量的积累效应

摘要

To explore the effect of potassium in tobacco leaf and forms of potassium in different layers of soil and to solve issue of low potassium content in tobacco in central Henan, an experiment was carried out in Xiangcheng, Xuchang of Henan province in 2013. Two levels of potassium fertilizer were used, and the tobacco were irrigated for three times, between accumulation of potassium in tobacco leaf and content of different forms of potassium in different depth of soil were analyzed using gray correlation analysis, The results showed that with the three irrigation and use of low levels of potassium fertilizer, correlation coefficient was 0.7059, indicating that tobacco potassium content was most closely correlated with slowly available potassium in the 0-20 cm soil. With the irrigation three times and use of high levels of potassium fertilizer, correlation coefficient was 0.7350, indicating that tobacco potassium content was most closely correlated with rapidly available potassium in the 40-60 cm soil and leaf potassium content was 1.88%, and it is also the best quality of tobacco leaves. With the decrease in potassium fertilizer rate and irrigation, their correlation with potassium content in tobacco and in different layers of soil was more significant. Frequent wet-dry alteration would help release slowly available potassium, thus increasing the level of rapidly available potassium. When fertilizer ratio was at N:P2O5:K2O=1:1:4.5, and irrigated for 3 times, increasing potassium fertilizer rate and frequency of irrigation was an good means to address the problem of low potassium content of tobacco in the late growth.%为探究烟叶钾素与不同土层不同种类土壤钾素关系和解决豫中烟区烟叶钾含量偏低的问题，在2013年河南省许昌市襄城县设置2个钾用量、3次灌水，采用灰色关联分析法对烟叶钾素积累与不同深度土层的不同形态钾素进行了关联分析。结果显示，当灌溉3次且施用低量钾肥时，烟叶钾含量与0~20 cm土层缓效钾关联最显著，关联度是0.7059。当灌溉3次且施用高量钾肥处理下的烟叶钾素与40~60 cm 土层的速效钾关联最显著，关联度度是0.7350，此时钾素含量最高达1.88%，烟叶质量也是最好。随着灌水减少与施钾量减少，烟叶钾与土壤钾含量关联度增加。干湿交替增加会造成各土层缓效钾释放，土壤速效钾增多。在氮磷钾比例为1：1：4.5且灌水3次条件下，在烟株生长后期，继续增施钾肥和增加灌水次数是解决烟叶钾素含量过低的重要途径。