摘要
通过开顶式气室控制CO2浓度，对盆栽大豆进行试验测定，研究了大气CO2浓度升高对大豆根系，重点是根瘤量和根瘤活性的影响。结果表明，大气CO2浓度升高，促进了大豆根系生长，大豆根体积、主根长、根鲜重均呈增长趋势，根冠比增加。CO2浓度为450、550、650和750μmol／mol时，与大气CO2背景浓度相比，在初花期，大豆根瘤数分别增加6．1％、15．9％、19．2％和26．5％，其中主根根瘤数增加较为显著，至鼓粒期，根瘤数增加幅度为7．8％～48．0％，增幅较初花期大，其中侧根根瘤量增加更多。同时，高CO2水平下，根瘤鲜重的变化与根瘤数基本一致。4种高CO2浓度下，初花期根瘤比固氮活性提高10．1％～24．0％，大于鼓粒期的6．0％～13．4％的增加幅度；单株根瘤固氮活性初花期增加10．6％～55．7％，鼓粒期则提高了20．0％～73．9％。
The root characteristics including root volume, root fresh weight, length of main root, ratio of root fresh weight to shoot fresh weight, root nodule number and nitrogen fixation activity of soybean were measured under ambient and elevated CO2 concentrations, and their responses to elevated CO2 were analysed. The results showed that growth of root system was promoted under high CO2 levels. The root nodule number increased by 6.1%, 15.9%, 19.2% and 26.5% at initial--flower stage under elevated （450, 550, 650 and 750μmol/mol） CO2, compared to the ambient air COz concentration. However, the root nod- ule number increased by 7.8%～48.0% at seed filling stage. On the other hand, the specific nitrogen fixalion activity based on root nodules fresh weight increased by 10.1%～24.0% and 6.0%～13.4%, at initiatl-flower. and seed filling stage. At the same time, the total nitrogen fixation activity per plant increased by 10.6%～55.7%and 20.0%～73.9% at two growth stages under four high CO2 levels.
出处
《大豆科学》
CAS
CSCD
北大核心
2006年第1期53-57,共5页
Soybean Science
基金
国家自然科学基金项目(70271062)
安徽省教育厅自然科学基金重点项目资助
关键词
大豆
CO2增加
根瘤
固氮活性
Soybean
Elevated CO2
Root nodule
Nitrogen fixation activity
