白刺叶片气孔特征对人工模拟降雨的响应

Response of leaf of Nitraria tangutorum Bobr stomata characteristics to artificial simulation of rainfall

以荒漠生态系统典型植物白刺(Nitraria tangutorum Bobr)叶片为研究对象,利用数码图像显微镜处理系统,研究了不同人工模拟增雨处理下的白刺叶片气孔密度及形态特征的变化情况。结果表明,荒漠植物固有特征决定了白刺叶片下表皮气孔密度大于上表皮,上表皮、下表皮气孔密度对增雨响应差异不显著(P>0.05)。增雨处理上表皮、下表皮气孔密度与对照差异显著(P<0.05)。相同增雨季节,50%处理下叶片气孔密度高于100%处理;不同增雨季节,气孔密度对生长季后期增雨响应更明显。白刺叶表皮气孔分布遵循"一细胞间隔(one cell spacing rule)"法则。增雨后叶片上表皮和下表皮气孔长度、宽度均有不同程度的增加,气孔形态特征对100%处理的响应较50%处理更为明显,且生长季后期增雨对叶片气孔形态特征的影响更大。

According to the regional characteristics of the climates and vegetations of desert ecosystem,the typical plant Nitraria tangutorum Bobr was chosen as research materials,the stomata densities and morphological characteristics of Nitraria tangutorum Bobr leaves in different artificial simulation of rainfall treatment were studied.Lengths,widths and ratio of lengths to widths of Nitraria tangutorum Bobr leaves were measured with a motic digital Imaging Microscope and the changes in stomata densities were evaluated.The result showed that desert plant stomata characteristics determined stomata density of lower epidermis is greater than the upper epidermis,stomata density of both upper and lower epidermis variation to the rainfall enhancement response was no significant difference（ P 0.05）.Upper and lower epidermis stomata density in all treatments and control had significant difference（ P 0.05）.The same precipitation enhancement season,stomata density of 50% treatment was higher than 100% treatment;in different seasons,stomata density response of the later growing season was more obvious.Nitraria tangutorum Bobr leaves epidermis stomata distribution corresponded one cell spacing rule.Artificial simulation of rainfall made upper epidermis and lower epidermis stomata length and width are increased to varying degrees.Stomata configuration characteristics variation of 100% treatment were more obvious than 50%treatment,and the impact of water addition on Stomata configuration characteristics in the later growing season was greater.