CO_2和O_3浓度倍增及复合效应对大豆生长和产量的影响

Effects of Double CO_2 and O_3 on Growth and Yields in Soybean

利用OTC 1型农田开顶式气室 ,模拟研究了大气中CO2 、O3 浓度倍增及其复合效应对大豆生长、根瘤和产量形成的影响 .结果表明 ,CO2 浓度倍增促进根系生长 ,固氮能力增强 ,植株高度和基部粗度增加 ,对发育期、绿叶数和绿叶面积影响不大 .O3 浓度倍增抑制大豆根系和茎的生长 ,固氮能力下降 ,叶片伤害使绿叶数和绿叶面积显著下降 ,衰老提前 .在CO2 和O3 的复合试验中 ,CO2 浓度增加明显缓解O3 浓度增加对大豆伤害和抑制作用 ,CO2 、O3 浓度持续倍增处理下大豆生长和固氮能力与CK的数量差异明显小于单一O3 浓度倍增与CK的数量差异 ,逐渐增加CO2 、O3 浓度的刺激作用和剂量效应使大豆生长后期伤害加重 ,绿叶数、绿叶面积显著下降 。

The effects of doubled CO 2 and O 3 interaction on growth and yields in soybean were investigated in the open top chamber for the first time. Increasing CO 2 can promote roots growth. The ability of nitrogen fixation enhanced. Plant height and base diameter increased. There are a little effect on the development stage, green leaf number and leaf area. Double O 3 concentration inhibited roots and stems growth. The ability of nitrogen fixation decreased. Green leaf number and leaf area decreased and advanced senescence course. This experiment also indicated that CO 2 enhancement could relax the injury and inhibition by O 3 to soybean seedling. The differences of growth and the ability of nitrogen fixation in soybean between lasted double CO 2 and control are less than that of single O 3 concentration. Stimulation and dose-effect of increasing CO 2 and O 3 concentrations to soybean gradually induced more serious damage in the development late. Green leaf number and leaf area decreased. The ability of nitrogen fixation increased markedly.