氮素形态对大豆根系形态性状及释放H^+的影响  

EFFECTS OF NITROGEN FORMS ON THE ROOT MORPHOLOGY AND PROTON EXTRUSION IN SOYBEAN

作　　者：乔云发[1] 苗淑杰[1] 韩晓增[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所,哈尔滨150081

出　　处：《大豆科学》2006年第3期265-269,共5页Soybean Science

基　　金：国家重点基础研究发展计划(973计划)项目(2005CB121101);黑龙江省攻关项目(GB05C201-01)资助

摘　　要：采用水培培养方法,研究了不同形态氮素对大豆根系形态性状及释放H+的影响。结果表明,不同形态氮素对根系形态特性的影响不同,表现为,NO3-N和NH4NO3-N促进根表面积增加;NH4+-N对根系的生长表现出抑制作用;而生物固氮处理,除根尖数随生育期的延长而增加外,其他根系形状几乎没有变化。NH4+-N处理根系释放出大量H+,且大豆根系受到NH4+-N的毒害,阻碍了根系对其它元素的吸收;而NO3-N处理,根系释放出大量OH-,对根系吸收其他元素的抑制作用较小,因此,生物量增加较明显;NH4NO3-N处理根际pH变化较小,促进大豆植株生长;而生物固氮处理,在生育前期,根瘤固氮能力较弱,不能及时为大豆生长提供充足的氮素,进而抑制大豆的生长,使生物量偏低。Solution culture experiment with soybean was made to study the effect of nitrogen forms on the root morphology and proton extrusion from roots. The results showed that there were significant differences between the effects of nitrogen forms and soybean root morphology. NO3^-N and NH4 NO3-N induced root surfacearea increased; NH4^＋-N inhibited root growth, however, the root morphology of N2-fixation treatment nearly did not have changes, except tips of root increased with time. The H＋ extrusion from root indicated that NH4^＋-N increased H^＋ extrusion, but the poison symptom when NH4^＋-N was an nitrogen source and amount of H＋ extrusion from NH4NO3-N treatment was in the middle of NO3-N,NH4^＋-N and NH4NO3-N. At early stage, N2-fixation treatment had low nitrogenase activity so that inhibited plant growth and low biomass.

关 键 词：氮素形态 大豆 根系性状 H^+ 

分 类 号：S565.1[农业科学—作物学]