玉米根系剖面分布对水分亏缺的响应  

Response of Profile Distribution of Maize Root System to Water Stress

作　　者：刘小芳[1,2,3] 张岁岐[1,2] 周小平[1,3] 慕自新[1] 刘立生[1] 

机构地区：[1]西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨陵712100 [2]中国科学院水土保持与生态环境研究中心,陕西杨陵712100 [3]中国科学院研究生院,北京100049

出　　处：《水土保持研究》2009年第2期181-185,共5页Research of Soil and Water Conservation

基　　金：国家高技术研究发展计划(863计划)(2006AA100202);国家自然科学基金项目(30571127);教育部新世纪优秀人才支持计划项目

摘　　要：在水分亏缺和正常供水(土壤含水量分别维持在田间持水量的40%～45%和75%～80%)两种水分条件下,采用土柱实验方法,研究了玉米杂交种户单四号(F1)及其父本803(♂)、母本天四(♀)根系剖面分布对水分亏缺的响应。结果表明:水分亏缺除了对父本的总根重无显著影响之外,使杂交种和母本的总根重以及3个品种的总根长和根系总表面积均显著下降。在剖面分布上,水分亏缺显著降低了杂交种和母本在表层土层中的根重和根表面积,使杂交种在表层和中层土层中的根长以及亲本在深层土层中的根长显著下降。可见,玉米杂交种响应中度干旱胁迫的形态学变化是减少上层干土中的根系生长,而增加深层土层中根系的相对生长,即其深层根系分布占总根系的比重较亲本高,这种根系剖面分布的优化导致杂交种较高的生物量积累和水分利用效率。The soil column experiment with 3 maize（Zea Mays L.）genotypes（F1 hybrid HD4,♂ 803 and ♀ T4）was conducted to study the profile distribution of root system under water stress and sufficient water supply conditions（40%～45% and 75%～80% of field capacity）.The results showed that water stress significantly decreased the total root weight,total root length and total root system surface area of 3 maize genotypes except the total root weight of ♂.As to the profile distribution of root system,water stress distinctively reduced the root weight and root surface area of both F1 and ♀ in upper soil layers,greatly declined the root length of F1 in upper soil layers and of ♂ and ♀ in lower soil layers.The results indicated that F1 decreased the percent of root in upper soil layers and increased it in lower soil layers in response to water stress.The percent of root in lower dry soil layers of F1 was higher than the parents,which led to higher biomass accumulation and water use efficiency.

关 键 词：玉米根系 剖面分布 水分亏缺 杂种优势 水分利用效率 

分 类 号：S152.7[农业科学—土壤学]