施氮对南疆干旱荒漠绿洲枣棉间作棉田根际微生物区系的影响研究

为了提高农林间作立体种植模式下的养分利用效率，保障干旱荒漠绿洲的农业可持续发展和农田生态环境的健康稳定，以新疆阿克苏地区典型的枣棉间作农田为研究对象，通过田间小区试验和室内测试，研究了0、150、300、450、600、750 kg/hm²等6种施氮水平对间作棉花根际土壤中细菌、真菌和放线菌数量的影响。结果表明：300 kg/hm²和450 kg/hm²施氮量能显著增加蕾期、花期和吐絮期微生物总数量。细菌和放线菌在整个生育期中蕾期数量最少，铃期和花期较高，吐絮期次之。真菌数量各个时期变化不大。适宜施氮量能增加铃期枣棉间作交际行棉花根际土微生物数量，有效的调节微生物区系。

Effects of Application Rates of Nitrogen Fertilizer on Microbial Populations under Red Date and Cotton Intercropping System of Southern Xinjiang arid desert oasis

A red date and cotton intercropping system was researched in Aksu Prefecture, Xinjiang was for improving the efficiency of nutrient use of agro-forestry-dimensional planting mode, and security sustainable agricultural development and healthy and stable of farmland ecological environment in the oasis. The field experiment was conducted in an attempt to understanding the number of micro-organism of cotton rhizosphere in a soil at various nitrogen application rates in a red date and cotton intercropping system. The different nitrogen rates were 0, 150, 300, 450, 600, and 750 kg/hm², respectively. The dynamic changes in the number of bacteria, fungi and actinomycetes in the cotton rhizosphere soil were investigated. The results indicated that microbial populations were significantly increased at nitrogen application rates of 300 and 450 kg/hm² nitrogen levels during flowering and boll opening period. The numbers of bacteria and actinomycetes were higher during flowering and boll opening period, followed by booting stage, the least number was found before anthesis. The numbers of fungi were slightly changed during the entire growing season. The numbers of microorganisms would be increased in rhizosphere soil red date and cotton intercropping of optimum nitrogen rate in cotton boll stage. It would be effective regulated the microbial flora in soil.