Bao, Aike

Wang, Suomin

Wu, Guoqiang

Xi, Jiejun

Zhang, Jinlin

English

University of Kentucky

University of Kentucky UKnowledge International Grassland Congress Proceedings XXI International Grassland Congress / VIII International Rangeland Congress Overexpression of the Arabidopsis AVP 1 Gene Enhanced the Salt‐ and Drought‐Tolerance Intransgenic Alfalfa (Medicago sativa L.) Aike Bao Lanzhou University, China Suomin Wang Lanzhou University, China Guoqiang Wu Lanzhou University, China Jiejun Xi Lanzhou University, China Jinlin Zhang Lanzhou University, China Follow this and additional works at: https://uknowledge.uky.edu/igc  Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/21/12-1/31 The XXI International Grassland Congress / VIII International Rangeland Congress took place in Hohhot, China from June 29 through July 5, 2008. Proceedings edited by Organizing Committee of 2008 IGC/IRC Conference Published by Guangdong People's Publishing House This Event is brought to you for free and open access by the Plant and Soil Sciences at UKnowledge. It has been accepted for inclusion in International Grassland Congress Proceedings by an authorized administrator of UKnowledge. For more information, please contact UKnowledge@lsv.uky.edu. 瞯 ]362　 瞯 　 Multifunctional Grasslands in a Changing World 　 Volume Ⅱ 　Grasslands/Rangelands Production Systems——— Developing Improved PlantsOverexpression of the Arabidopsis AVP1 gene enhanced the salt‐and drought‐tolerance intransgenic alfalfa (Medicago sativa L .)A i‐Ke Bao , Suo‐Min W ang 倡 ,Guo‐Qiang W u , Jie‐Jun X i , Jin‐L in ZhangThe K ey L aboratory o f G rassland A gro‐ecosystem o f the M inistry o f A griculture ,School o f Pastoral A griculture Science and Technology , L anz hou University , L anz hou 730000 , Peop le摧s Republic o f China .倡 Corresponding author E‐mail : smwang＠ lz u .edu .cnKey words : H ＋ ‐PPase ,AV P1 gene ,transgenic alfalfa ,salt‐and drought‐toleranceIntroduction there have been not any reports about improving the salt and drought tolerance of alfalfa by introducing AV P1 . Weassume that transgenic alfalfas expressing the H ＋ ‐PPase gene are indeed more resistant than wild‐type plants to salt stress andsoil water deficit . This assumption is to be testified in this study .Materials and methods Hypocotyls (２‐４ mm) cut from ４‐day‐old seedlings were used as explants for transformation mediated byA grobacterium strain GV３１０１ carried the AV P1 gene which was granted by Gaxiola in ２００４ . The transgenic plants wereidentified by PCR method . The expression of AV P1 in transformants was determined using RT‐PCR . The cationconcentrations were measured using a flame spectrophotometer . The solute potential was determined with a cryoscopicosmometer . The net photosynthetic rate was measured using an automatic photosynthetic measuring apparatus . The MDAcontent was determined using thiobarbituric acid ( TBA ) protocol . The relative membrane permeability of leaf cells wasdetermined using a conductivity meter .Results A high efficiency A grobacterium‐mediated transformation system in alfalfa was established . This system showed highertransformation efficiency ( about ２ .１％ ) and a shorter time ( about １８‐１９ weeks) compared with most of previous procedures foralfalfa . By using this system , ２０ KanR plants were obtained in this study . Expected PCR products ( about ３０３ bp ) wereobtained from １９ lines of ２０ KanR lines , suggesting that the AV P1 gene was integrated into the chromosomal DNA of thesealfalfa plants ( Figure １A ) . To measure the expression level of AV P1 mRNA , RT‐PCR was performed on random eighttransgenic lines together with wild‐type plants . All lines expressing the AV P1 gene and , AV P1 mRNA levels varied amongindividual transformants ( Figure １B) , and line １ ( highest ) and line ８ ( lowest ) were chosen for further physiological assays .T ransgenic alfalfa grew well in the presence of ２００ mM NaCl ( Figure ２ ) and in the environment of withholding water andrewatering ( Figure ３A ,B) , while wild‐type plants exhibited wilting and grow th inhibition , even death . Compared with wild‐type plants , transgenic plants accumulated more Na＋ , K ＋ and Ca２ ＋ in leaves and roots .Figure 1 Molecular detection o f al f al f a trans f ormants .(A ) PCR analysis ; (B) RT‐PCRanalysis .　 　Figure 2 Transgenic al f al f a p lants showed enhancedsalt tolerance . Plants o f wild type and two transgeniclines at 200 mM NaCl f or 10 d .Figure 3 Transgenic al f al f a p lants showed enhanced drought tolerance . (A )The well water soil was allowed to dryby withholding water for 8 d . (B) Then soil was rewatered to f ield capacity f or 4 d .Conclusions The overexpression of A rabidopsis H ＋ ‐PPase gene confers salt‐and drought‐tolerance in alfalfa . This is associatedwith the increased sequestration of Na＋ into vacuole , which resulted in the overexpression of H ＋ ‐PPase gene and led toaccumulation of solutes and maintaining ion homeostasis especially intracellular K ＋ and Na ＋ homeostasis .

Overexpression of the \u3ci\u3eArabidopsis AVP\u3c/i\u3e 1 Gene Enhanced the Salt‐ and Drought‐Tolerance Intransgenic Alfalfa (\u3ci\u3eMedicago sativa\u3c/i\u3e L.)

https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=3286&amp;context=igc

Overexpression of the \u3ci\u3eArabidopsis AVP\u3c/i\u3e 1 Gene Enhanced the Salt‐ and Drought‐Tolerance Intransgenic Alfalfa (\u3ci\u3eMedicago sativa\u3c/i\u3e L.)

Abstract

Similar works

Full text

Available Versions

University of Kentucky