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作 者 ：李中阳 宋正国 樊向阳 杜臻杰

期 刊 ：植物营养与肥料学报 2013年 19卷 1期 页码：21-26

关键词：CO2浓度升高；水稻；品种；营养元素；根形态；

Keywords:elevated CO2, rice, cultivar, nutrient element, root morphology,

摘 要 ：本文利用水培试验研究了CO₂浓度升高对水稻幼苗生物量、养分含量和根形态的影响，探讨 了CO₂浓度升高下粤杂889（YZ）和荣优398（RY）幼苗养分吸收和根系形态的差异性。结果表明， 与CO₂浓度正常水平（对照）相比，CO₂浓度升高显著增加了2个水稻品种幼苗根系、茎叶和总生物量，YZ分别增加58.33%、27.96%、33.16%; RY分别增加45.87%、34.17%、36.07%。同时，CO₂浓度升高增加了2个水稻品种的根冠比。CO₂浓度升高显著降低了2个水稻品种茎叶中的N、P、K、Ca、Mg和Fe含量，这是“稀释效应”的结果; 但YZ幼苗中S含量显著增加，2个品种幼苗Mn含量均显著增加。CO₂浓度升高显著增加了2个水稻品种的幼苗根系根毛数、总根长、表面积，降低幼苗粗根比例，增加了细根比例。CO₂浓度升高增加了细根在总根长中的比例，有利于水稻对养分的吸收，导致部分营养元素含量增加; 但CO₂浓度升高条件下水稻生物量的增加使大部分营养元素含量降低。同时，CO₂浓度升高对水稻幼苗生物量、养分吸收和根形态的影响存在显著的品种差异。

Abstract:A hydroponic experiment was conducted to study the effects of elevated CO₂ on the rice seedlings biomass, nutrient concentration and root morphology of rice Yueza889(YZ) and Rongyou398(RY). The results show that compared with the control, the root, shoot and total dry weights of YZ and RY are increased significantly under the elevated CO₂, the weights are increased by 58.33%, 27.96% and 33.16% for YZ and increased by 45.87%, 34.17%and 36.07% for RY, respectively. The roots to shoot ratios of the two rice cultivars are also increased under the elevated CO₂. The shoot N, P, K, Ca, Mg and Fe contents of the two rice cultivars are decreased under the elevated CO₂, while the Mn contents are increased. The shoot S concentration of YZ is increased, while the shoot S concentration of RY is decreased. The root tip numbers, length and surface area, the proportion of fine roots are also increased under the elevated. The elevated CO₂ increases the proportion of fine roots, and this is a favorable change for rice to uptake more nutrition elements which could be one of the main reasons for increases of some elements concentrations, but the elevated CO₂ dilutes most elements in this pot studies. There are obvious variations of biomass, nutrient concentration and root morphology between the two rice cultivars.

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