CO2浓度倍增对10种禾本科植物叶片形态结构的影响

在CO_2正常浓度(350μL/L)和倍增(700μL/L)条件下,对小麦(Triticum aestivum L.)、半野生小麦(T.aestivum ssp.tibeticum)、大麦(Hordeum vulgare L.)、野大麦(H.brevisubulatum(Trin.)Link)、水稻(Oryza sativa L.)、野生稻(O.meyeriana subsp.granulata)、谷子(Setaria italica(L.)Beauv)、狗尾草(S.viridis (L.)Beauv)、高粱(Sorghum vulgare Pers.)和玉米(Zea mays L.)等10种禾本科植物幼苗期叶的形态结构进行比较研究。结果表明,在CO_2浓度倍增条件下,除野大麦和玉米外,其它几种禾本科植物的叶片厚度普遍增加;表皮细胞密度下降(野大麦和谷子的远轴面除外)。其中C_3种类的平均气孔密度和气孔指数下降,C_4种类则呈相反趋势。在CO_2浓度倍增条件下,栽培种类表皮细胞密度和维管束鞘细胞中的叶绿体数明显增加,野生种类则呈相反趋势。气孔密度与气孔指数基本呈正相关。

EFFECT OF CO_2 CONCENTRATION DOUBLING ON THE LEAF MORPHOLOGY AND STRUCTURE OF 10 SPECIES IN GRAMINEAE

The effects of CO2 concentration on leaf thickness, chloroplast numbers in the bundle sheath cell, epidermal cell density, stomatal density, stomatal index, stomatal size were compared in 10 species in Gramineae: Triticum aestivum L. , T. aestivian ssp. tibeticum, Hordeum vulgare L. , H, brevisubulatum (Trin.) Link, Oryza saliva L. , 0. meyeriana ssp. granulata, Setaria italica (L.) Beauv, 5. viridis (L.) Beauv, Sorghum vulgare Pers. , Zea mays L. following their exposure to doubled carbon dioxide (700 L/L) and ambient carbon dioxide concentration (350 L/L). The results indicated that different species of plants might vary in their response to doubled CO2. In general , the leaves became thicker under the elevated CO2 condition. The mean stomatal density of the C3 species was decreased in doubled CO2, whereas the results of C4 species showed an inverse trend. The epidermal cell density and the chloroplast numbers of the bundle sheath cell in the wild plant species were less than those in the control under CO2 enrichment. The stomatal density was positively correlated with the stomatal index. Finally, the general pattern of structural variation under differ- ent CO2 concentrations was proposed, and their implication to the research of global change was discussed as well.