不同地理类型青杨派古树扦插苗对干旱胁迫的响应  

Response of Different Geographic Types of Ancient Poplar Cuttings to Drought Stress

作　　者：潘立 陆燕元[2] PAN Li;LU Yan-yuan(College of Accounting,Southwest Forestry University,KunmingYunnan 650224,P.R.China;Key Laboratory of Southwest Biodiversity Conservation,State Forestry Administration,Southwest ForestryUniversity,Kunming Yunnan 650224,P.R.China)

机构地区：[1]西南林业大学会计学院,云南昆明650224 [2]国家林业局西南地区生物多样性保育重点实验室,西南林业大学,云南昆明650224

出　　处：《西部林业科学》2021年第3期8-19,共12页Journal of West China Forestry Science

基　　金：国家自然科学基金(31460181);云南省教育厅科学研究基金项目(2021J0169);中国学位与研究生教育学会农林学科工作委员会研究课题(2019-NLZX-YB43)。

摘　　要：为了揭示不同地理类型古杨树对环境胁迫的生理及分子适应机理,本试验以胸径≥1 m,树龄在300~500 a生的青杨派三脉青杨、乡城杨和康定杨古杨树扦插苗为对象,采用自然干旱胁迫的方法,研究不同地理类型古杨树在干旱胁迫过程中生理生化及抗逆基因表达的差异响应。研究结果表明,在水分供应充足的条件下,干热河谷型的三脉青杨的光合参数较低,受到干旱胁迫后反应最为敏感,叶片相对含水量(RWC)迅速下降,抗氧化酶APX和SOD活性以及抗逆基因SOD瞬时表达量均显著增加,O^(2-).积累量降低,但干旱强度加剧后三脉青杨植株形态受损程度最重,表明三脉青杨在中轻度的干旱胁迫下适应能力较好。温湿型乡城杨受旱后抗逆基因Lea3和SOD瞬时表达量均同时升高,植株叶片的光合能力稳定,表明其对干旱的适应的综合能力较强,因此,乡城杨的分布范围要远远大于其它两种。分布于高海拔地区的寒湿型康定杨受干旱后虽然抗氧化酶SOD和APX活性以及SOD基因瞬时表达量均显著升高,但H_(2)O_(2)积累量也增幅明显,叶片含水量及光合特性明显下降,表明其对干旱胁迫的适应性较弱。由此可见,不同的抗旱基因在不同的地理类型古杨树中发挥的作用不同,对干旱的响应存在差异,反映出它们对自身特定气候的适应机制。In order to revealed the adaptive mechanism of differential geographical types of ancient Poplar cuttings to environmental stress,three geographic types of Populus trinervis,P.xiangchengensis and P.kangdingensis with a diameter at breast height≥1 m and tree ages between 300 and 500 years were selected as subjects to study the differential responses of physiological,biochemical and stress-resistant gene expression of under natural drought stress process.The results showed that under the conditions of sufficient water supply,compared with the other two tree species,the photosynthetic parameters of the P.trinervis,which was the dry-hot valley type was lower,and was sensitively to the mild drought stress,such as leaf water content decreased rapidly,the antioxidant enzyme APX and SOD activities,and the transient expression of stress resistance gene SOD also increased significantly,so the O^(2-).accumulation was effectively eliminated,and the cells were less damaged.However,when the drought intensity intensified,the degree of plant damage was the heaviest,indicating that the dry-hot valley type of P.trinervis had better adaptability under moderate to mild drought stress.The instantaneous expression of stress resistance genes Lea3 and SOD in the temperate-rural types of P.xiangchengensis were increased simultaneously under drought stress,which enabled the plant leaves to maintain relatively stable photosynthetic capacity,indicating that its comprehensive ability to adapt to drought stress was strong,so its distribution range is much larger than the other two.The cold-wet type P.kangdingensis distributed in the high altitude area showed although an increase trend of antioxidant enzymes SOD and APX,and the transient expression of the stress resistance gene SOD after drought stress,the H_(2)O_(2) accumulation still increased significantly,so that the leaf water content and photosynthetic indicators were both inhibited significantly,indicating that its adaptability to drought stress is weak.In general,different drought-re

关 键 词：地理类型 古杨树 干旱胁迫 响应 

分 类 号：S792.113[农业科学—林木遗传育种]