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作 者 ：李宁毅,时彦平,王吉振

期 刊 ：西北植物学报 2012年 8期 页码：1626~1631

关键词：S3307；百日草；水分胁迫；光合特性；叶解剖结构；

Keywords:uniconazole, Zinnia elegans Jacq., water stress, photosynthetic characters, leaf structure,

摘 要 ：以百日草‘芳菲1号’为试材，研究不同水分胁迫下烯效唑(S₃₃₀₇)对其幼苗生长、光合特性及叶解剖结构的影响，以明确S₃₃₀₇对百日草的抗旱作用及其机理。结果显示：(1)在水分胁迫下，百日草的生长均受到不同程度的抑制，叶绿素含量显著降低，光合作用受到抑制，叶解剖结构有所变化。(2)S₃₃₀₇处理后，均能够显著降低所对应的不同程度水分胁迫下百日草的株高，显著增加茎粗、叶面积、叶片厚度、栅栏组织厚度和根冠比，显著增加叶绿素含量，提高百日草的净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)和水分利用效率(WUE)。研究表明，S₃₃₀₇能够提高百日草的抗旱性，而且在轻度和中度水分胁迫下P_n的下降主要是由气孔因素引起，而在重度水分胁迫下光合速率的下降是由非气孔因素引起的。

Abstract:In order to understand the effects and mechanism of the drought resistance of uniconazole on Zinnia seedlings growth,the photosynthetic characteristics and leaf anatomical structure were studied of Zinnia,‘Fangfei 1’ using uniconazole under water stress.The results showed that:(1)Under water stress,the growth of Zinnia was inhibited at different degrees,chlorophyll content was decreased significantly,photosynthesis was inhibited,some changes were occurred in leaf structure.(2)Under different water stress,uniconazole could reduce the plant height,increase the stem diameter,leaf area,leaf thickness.Palisade tissue thickness,root shoot ratio and chlorophyll content increased significantly.The net photosynthetic rate(P_n),transpiration rate(T_r),and stomatal conductance(G_s) and water use efficiency (WUE) were improved.The results suggested that uniconazole could strengthen the drought resistance of Zinnia seedling,the decline of P_n was considered as a result of stomatal restriction under light and moderate water stress,but nonstomatal restriction under severe water stress.

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