王娇毕业论文定稿MicrosoftWord文档.docVIP

石河子大学 学 士 学 位 论 文 膜下滴灌下水氮运筹对棉花根冠生长及水分利用效率的影响 学生姓名 学号专业 农 学 年级、班级 2007级农学方向（2）班 指 导 教 师 罗宏海副教授 所在学院 农学院 中国·新疆·石河子 2011年6月膜下滴灌下水氮运筹对棉花根冠生长及水分利用效率的影响 摘要：水氮运筹方式对膜下滴灌棉花根冠生长及水分利用效率影响。结果表明：基肥20%+追施80%70%）的水分分布特征，。生育期间65%-75%并适当增大生育中后期关键词：棉花；水氮运筹；根冠生长；水分利用效率；膜下滴灌 Effects of irrigation and nitrogen application regimes on root and seedling growth and water use efficiency of cotton with drip irrigation under mulch Abstract：Under the condition of the soil column with high yield cultivation cotton varieties of Xinluzao 13 as materials, the effects of irrigation and nitrogen application regimes on root and seedling growth and water use efficiency with drip irrigation under mulch were studied. The results showed that under the condition that the ratios of base nitrogen to dress nitrogen fertilizer were 20% to 80% (N2), the soil mositure distribution with the soil relative moisture content at sowing and growing stages were 80% and 70% respectively (W3), Spur the root to stretch in deeper soil and increased the water use efficiency in deeper soil layer, optimized the relation of root and seedling and promoted the reproductive growth, and raised the yield and water use efficiency. Our results emphazied the importance of pre-sowing irrigation to increase the water storage of deeper soil layers. In addition, a sustained soil moisture level of 65%-75% of field capacity and increased the allocation ratio of nitrogen during the middle and late growth stages are essential for achieving higher yield and water use efficiency with drip irrigation under mulch. 朗读 显示对应的拉丁字符的拼音 字典 ?2010商务工具译者工具包关于 Google 翻译博客隐私权政策帮助Keywords：Cotton; Irrigation and nitrogen application; Root and seedling growth; Water use efficiency; Drip irrigation under mulch 根系是支撑作物地上部生长、吸收水分和营养成分、将土壤作物系统联为整体的重要功能性器官，其数量的多少、功能的强弱直接制约地上部分的生长发育和产量及水分利用效率的高低[1,2]。土壤水分和氮素是影响作物根系生长发育的最重要因素，合理灌溉施氮是促进作物根系生长发育、提高产量的重要途径[3]。因此，如何利用水氮间的协同作用，探寻通过调控土壤水氮供应量和时期，进而调节根系的生长，调控地上部生长和产量形成，从而