3个新引进黑杨无性系间水分利用效率差异性研究  

Discrimination of water use efficiency (WUE) among three Populus deltoids clones

作　　者：郭鹏[1] 邢海涛[1] 夏新莉[1] 尹伟伦[1] 

机构地区：[1]北京林业大学林木育种国家工程实验室

出　　处：《北京林业大学学报》2011年第2期19-24,共6页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(30730077;30972339);林业公益性行业科研专项(200704040;201004004);"973"国家重点基础研究发展计划项目(2009CB119101)

摘　　要：北美杂交黑杨是一种速生但高耗水的树种,筛选高水分利用效率的黑杨品系有重要的理论和实际意义。本文研究了不同水分处理下,3个不同黑杨无性系DN-2、R-270、NE-19的长期水分利用效率(WUEL)、瞬时水分利用效率(WUEi)、叶片碳同位素组成(δ13C)、光合速率(Pn)、气孔行为及其相互关系。结果显示:无性系间WUEL、WUEi、δ13C、Pn、气孔行为都存在明显的差异。说明在黑杨无性系间也存在水分利用效率的差异性。其中NE-19是各处理中表现最优的无性系,具有最高的WUEL、WUEi、δ13C、Pn,而气孔密度和气孔导度最低。分析表明,气孔密度和气孔导度是导致无性系间WUEL、WUEi、δ13C、Pn差异的主要原因。在充分供水条件下δ13C和WUEL相关性最好,但在胁迫处理下其相关性下降。因此,在水分充足的情况下δ13C可作为筛选高水分利用效率品系的可靠指标。ERECTA是第1种在拟南芥中被发现的可调控水分利用效率的基因,从黑杨中克隆并分析该基因,RT-PCR结果表明,ERECTA在黑杨中也具有相似的功能。Populus deltoids is a fast growing and high water-consuming species.It is necessary to choose clones with high water use efficiency when they are introduced to China.In our test,long-term water use efficiency （WUEL）,instantaneous water use efficiency （WUEi）,foliar carbon isotope composition （δ13C）,photosynthesis,stomatal density and stomatal conductance（Gs） of three P.deltoids clones（DN2,P.deltoides×P.nigra;R-270,P.deltoides×P.nigra;NE-19,P.nigra×（P.deltoides×P.nigra）） were studied under different water treatments.The results showed that significant differences in these parameters were detected among three clones,indicating the variation of water use efficiency among three clones.NE-19 was the best clone,with the highest WUEL,WUEi,δ13 C and net photosynthetic rate（Pn） and the lowest stomatal density and Gs.Therefore,we make a conclusion that stomatal density and conductance are the major factors which could lead to the variation of Pn and WUE i and in turn affect WUEL and δ13C.δ13 C could be a good indicator to evaluate the WUEL of clones,which was correlated with WUEL under sufficient water supply;however,the correlation decreased under water stress.ERECTA gene is the first gene which could regulate plant transpiration efficiency in Arabidopsis.A cDNA clone,designated PdERECTA,was isolated from P.deltoids.RT-PCR indicated that PdERECTA gene may have the similar function in P.deltoids.

关 键 词：ERECTA基因 美洲黑杨 叶片δ13C 净光合速率 气孔密度 气孔导度 水分利用效率 

分 类 号：S718.43[农业科学—林学]