氮素营养对盐碱地棉花生长及生理特性的影响

Effects of Nitrogen Nutrition on the Growth and Physiological Characteristics of Cotton in Saline Soil

为研究不同氮肥施用方式对棉花生长及生理特性的影响。在东营滨海盐碱地设置棉花大田试验,设不施氮肥、氮肥基施、氮肥分施(1/2基施、1/2花期追施)、控释氮肥4个处理,测定分析棉花生物量和氮素积累及氧自由基代谢相关酶活性变化等。结果表明:棉株氮素和地上部生物量的积累符合Logistic方程;施氮能增加作物对氮素的吸收,并能提高作物叶片氮素浓度,花铃期是植株氮素和生物量积累的关键时期;控释氮肥及氮肥分施皆能有效提高棉花叶片SOD和POD活性,降低MDA及脯氨酸含量,进而提高作物抗逆性减缓衰老;控释氮肥处理子棉产量和氮肥农学利用率最高,子棉产量2年分别比不施氮肥处理提高26.8%,氮肥农学利用率较氮肥基施和氮肥分施处理平均增加0.99,0.29 kg/kg。控释氮肥的施用能有效提高棉花的抗逆性减缓衰老,并能获得较高产量,适宜在盐碱地施用。

The field experiment was conducted in saline soil in order to study the effects of nitrogen application on growth and physiological characteristics of cotton in Dongying. The nitrogen fertilizer used by no nitrogen（ CK）,base application,split application（ 1 /2 used for base application and 1 /2 used at flowering stage） and controlledreleased nitrogen. The results showed that the cotton biomass and nitrogen accumulation followed logistic model. The uptake of nitrogen in cotton and concentration of nitrogen in cotton leaf increased with nitrogen application. The critical period of biomass and nitrogen accumulation was blooming-bolling stage. Moreover,the SOD and POD activity of cotton leaves and crops resistance to senescence increased in controlled release nitrogen fertilizer and split application of nitrogen treatments. However,the MDA and proline content reduced. The yield of cotton seed and nitrogen agronomy efficiency were the highest in controlled release nitrogen fertilizer treatment. The yield of cotton seed increased by 26. 8% in two years,compared with CK and split application of nitrogen fertilizer. The nitrogen fertilizer utilization rate increased by 0. 99,0. 29 kg / kg compared with base fertilizer and split application treatments. Controlled release nitrogen fertilizer application is suitable for the coastal saline soil and can effectively improve the resistance of cotton as well as getting high yield.