摘要：

为了进行苗期转ScALDH21基因棉花的耐盐性鉴定。以新农棉1号的T₄转ScALDH21基因棉花株系为研究材料,分别在大田条盆及温室盆栽条件下进行试验。大田条盆试验中,分别统计0.4%,0.5%,0.6%盐土栽种下转ScALDH21基因与受体棉花的叶绿素含量和存活率,并测定其净光合速率、气孔导度、蒸腾速率及瞬时水分利用效率;室内盆栽试验中,分别统计NaCl(150 mmol/L)和清水处理下不同棉花株系MDA、POD、木质素、Na⁺、K⁺及Na⁺/K⁺值。结果表明,在盐胁迫条件下,与受体棉植株相比,转ScALDH21基因棉株的存活率上升,叶绿体含量增加,净光合速率、气孔导度、蒸腾速率以及瞬时水分利用效率均提高;MDA含量降低,POD活性上升,木质素含量增加。从形态及生理指标层面验证了转ScALDH21基因棉花在苗期提高了植株的耐盐性。

关键词: 棉花, ALDH21基因, 耐盐, 光合作用, 生理指标

Abstract:

In order to analyze the salt tolerance of ScALDH21 transgenic cotton at seedling stage,T₄ transgenic ScALDH21 cotton lines and its recipient Xinnongmian 1 was used as the research material,and the research were executed under field and greenhouse conditions.In field condition,the plant materials were planted with 0.4%,0.5% and 0.6% salt soil in stripe pots,respectively.The growth phenotype,the chlorophyll content and survival rate of each transgenic lines and its recipient under different salt concentrations were observed and monitored,and their net photosynthetic rate,stomatal conductance,transpiration rate and instantaneous water use efficiency were measured.In greenhouse condition,the contents of MDA,POD activity,lignin,Na⁺,K⁺ and Na⁺/K⁺ were determined after 150 mmol/L NaCl and water treatment respectively.Compared with the recipient cotton,the survival rate,chloroplast content,net photosynthetic rate,stomatal conductance,transpiration rate and instantaneous water use efficiency of ScALDH21 transgenic cotton were increased under salt stress.MDA content decreased,POD enzyme activity increased,lignin content increased.From the aspect of morphology and physiological indexes, it was verified that the transgenic ScALDH21 cotton improved the salt tolerance of the plant at the seedling stage.

Key words: Cotton, ALDH21 gene, Salt tolerance, Photosynthesis, Physiological indicators