不同倍性冬小麦根系生长对水分和密度的响应  

Effects of Water and Planting Density on Root Character of Different Ploidy Wheat

作　　者：孙婴婴 刘立生[1] 张帆[1] 张岁岐[1,2] 

机构地区：[1]西北农林科技大学/黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《中国农学通报》2015年第3期74-81,共8页Chinese Agricultural Science Bulletin

基　　金：国家高技术研究("863")发展计划项目"农田水肥联合调控技术与设备"(2011AA100504)

摘　　要：为探讨不同倍性冬小麦根系生长对水分和密度的响应,利用3个倍性小麦材料(二倍体栽培一粒、四倍体栽培二粒、六倍体现代品种‘长武134’)通过在不同水分条件下进行密度试验,研究其拔节期和开花期的根系生长和水分消耗特征,结果表明,在拔节期密度的增加显著提高了小麦根系干物质累积量和根长总量,而竞争加剧使得高密度处理的根量优势到花期显著减弱;拔节期四倍体和六倍体的根重和根长均表现出高于二倍体的趋势,花期各倍性材料之间的根重无显著差异,但是高倍性材料仍保持显著的根长优势;干旱和高密度处理均减少了花期根系在表层的分布,增加了深层根系的分布量,利于深层水分的利用。最终得到结论,六倍体现代小麦根系在不同生育期的根系干物质分配更利于产量增长,而在水分亏缺地区构建合理的群体有益于根系下扎,从而促进土壤深层水分的利用,并提升产量。In order to illustrate effects of water and planting density on root character of different ploidy wheat, three different ploidy wheat （the diploid Triticum monocoecum, the tetraploid Tritieum dicoecum, and the hexaploid Triticum aestivum ＇Changwu 134＇） were planted in field experiment conducted in Yangling. Three planting densities （low, medium and high density, exactly 1, 2.5 and 4 million plants per hectare） were set, and two kinds of water conditions were taken as well respectively one with normal rainfall and irrigation while the other with none, to investigate the response of root dry weight, root length, water consuming characters to the density and water conditions. The results indicated that： the root dry weight at flowering stage did not decrease with the ploidy increase, root length of the tetraploid and the hexaploid was higher than that of the diploid under water-supply condition, the hexaploid was more sensitive to water while the water consuming showed no significant difference among the three ploidy wheat; the root distribution and proportion of total root weight and length in surface soil declined under water deficit, but the root distributed in the depth increased, so that the water in deep soil was used more efficiently; higher density brought in more competiveness in surface soil ,thus the root grew down and the proportion in depth increased, more water in deep soil was then taken. All abovementioned results provide the theory basis for wheat breeding and planting in the arid and semi-arid area.

关 键 词：群体大小 进化材料 根系剖面分布 水分亏缺 

分 类 号：S314[农业科学—作物栽培与耕作技术] S512.1[农业科学—农艺学]