Responses of Photosynthetic Physiological Process of a Poplar with Overexpressed PIP1 Gene to Drought Stress and Rehydration

【Objective】The responses of photosynthetic process to drought stress and re-watering of the wild type and PtPIP1;3（GenBank accession No.MN795092 ptopip1.3）transgenic poplar variety'84K'（Populus alba×P.glandulosa'84K'）were compared to analyze the limitation factors to photosynthesis in order to further understand the function of aquaporin PIP1 in regulation of CO2conductance and the influences on photosynthesis.【Method】The wild type and PtPIP1;3 transgenic poplar variety'84K'were subjected to severe drought stress（The soil water content reaches 35%of the field water capacity）and re-watering.The gas exchanges and chlorophyll fluorescence parameters of the leaves were measured,with which the mesophyll conductance（gm）and other relevant parameters were calculated.Then the regulation of aquaporin in CO2conductance and photosynthesis after drought stress and re-watering was analyzed.【Result】Net photosynthetic rate（Pn）,stomatal conductance（gs）and transpiration rate（Tr）of transgenic poplars were significantly higher t