导入TaNHX2基因提高了转基因普那菊苣的耐盐性  

Introduction of TaNHX2 gene enhanced salt tolerance of transgenic puna chicory plants

作　　者：张丽君[1,2] 程林梅[2] 杜建中[2] 郝曜山[2] 王亦学[2] 李贵全[1] 孙毅[1,2] 

机构地区：[1]山西农业大学,太谷030081 [2]山西省农业科学院生物技术研究中心,太原030031

出　　处：《生态学报》2011年第18期5264-5272,共9页Acta Ecologica Sinica

基　　金：国家转基因生物新品种培育重大专项(2009ZX08003-017B);山西省农科院攻关项目(Ygg0912)

摘　　要：我国部分地区土地盐碱化的日益严重,对作物的生长和生态环境产生了显著影响,因此通过植物基因工程手段培育耐盐碱的转基因作物品种对改善作物的生存能力和生态环境,提高作物产量具有重要的意义。采用农杆菌介导法将来自小麦(Triticum aestivum Linn)的Na+/H+逆向转运蛋白的基因(vacuolar Na+/H+exchanger or antiporter,简称NHX、NHE或NHA),对普那菊苣(Cichorium intybus L.cv.Puna)植株进行了遗传转化。经抗生素筛选以及针对TaNHX2基因的PCR检测和Southern杂交分析,证明获得了28株转TaNHX2基因的普那菊苣植株。用不同浓度NaCl溶液对普那菊苣野生型和T0代种子、愈伤组织和幼苗生长情况胁迫的研究,结果表明:转TaNHX2基因普那菊苣植株表现出一定的抗性,比野生型明显提高。在300 mmol/LNaCl胁迫下转基因植株种子的出芽率、外植体出愈率和分化率是野生型植株的2—4倍,而500 mmol/L NaCl浓度为野生型和转基因外植体能否生长的临界点。在此临界值下野生型外植体或不能形成愈伤组织、或幼苗不能正常生根、或已生根幼苗不能正常成长,而转基因外植体可以继续形成愈伤组织并正常生根生长。同时对500 mmol/L NaCl胁迫下野生型和转基因普那菊苣幼苗其体内丙二醛含量(MDA)、过氧化氢酶(POD)和超氧化物歧化酶(SOD)活性进行测定,结果表明转基因植株比野生型植株的MDA含量降低了1—3倍,POD活性提高了1—3倍,SOD活性提高了2—3倍,分析发现普那菊苣的耐盐性与其体内的丙二醛含量(MDA)、过氧化氢酶(POD)和超氧化物歧化酶(SOD)活性密切相关。The growing severity of land salinization and alkalization in some areas of China has resulted in adverse impacts on crop production and agriculture-ecological environment.Soil salinity is one of the major limiting factors affecting crop growth,development and yield in arid and semiarid regions of China.Therefore,breeding for saline and alkaline tolerant crop varieties through genetic engineering approaches is of great significance for improving the crop survivability in saline and alkaline conditions and ecological environment,as well as for enhancing crop production.With the development of molecular biology and genetic transformation technology,numerous genes related to saline and alkaline tolerances have been found and cloned.Introduction of these genes into various plants has achieved rapid improvement of their tolerances saline and alkaline conditions.Cichorium intybus L.cv.Puna.belonging to Asteraceae family is commonly known as witloof cichory and widely distributed in northern,and central China.In this study,a wheat（Triticum aestivum Linn）vacuolar Na＋/H＋ exchanger gene（TaNHX2）,in connection with plant salt tolerance,was introduced into puna chicory using Agrobacterium-mediated transformation approach.Puna chicory leaf segments were precultured for 2—3 days before being co-cultivated with the Agrobacterium strain,pBin438-TaNHX,which containing the target gene2 Transformed buds were selected on the MS medium containing kanamycin（80mg/L） and Cefalexin（1000mg/L）,and 28 putative transgenic lines were obtained and used for further molecular and biological assay.Analysis of the transgenic plants was performed by using PCR and Southern blot hybridization,which proved that the wheat vacuolar Na＋/H＋ exchanger gene was successfully integrated into puna chicory genome.Effects of NaCl concentration on growth of wild type and T0 seed germination,callus induction and seedling growth were investigated.The results indicated that transgenic puna chicory explants tolerated certain concentrations of

关 键 词：普那菊苣 TaNHX2 转基因 耐盐性 

分 类 号：S548[农业科学—作物学]