转AtNHX1基因马铃薯田间盐胁迫下的生理反应及耐盐性的综合评价

摘要

以转AtNHX1基因的8个马铃薯株系(1、2、4、6、8、15、18、19)和未转基因的“甘农薯2号”(CK)为材料,在正常地以及全盐含量分别为0.56％、0.29％的高盐和中盐地上种植,分析其生长和生理指标的变化,通过隶属函数法、相关分析和聚类分析等方法综合评价耐盐性.结果表明:随着盐浓度的增加,转基因株系的株高、叶面积扩展率、单株产量、叶绿素的含量、超氧化物歧化酶(SOD)活性以及脯氨酸含量的上升幅度均高于对照植株(为对照的1.17～3.96倍).而丙二醛(MDA)、相对电导率显著低于对照植株,为对照的63.07％～78.4％和82.7％ ～ 86.35％.根据生长和生理指标综合评价各株系的耐盐性,筛选出1个强耐盐株系和3个较强耐盐株系,各株系耐盐性由强至弱为:19＞ 15＞8＞4＞ 18＞2＞1 ＞6＞CK,AtNHX1的导入显著提高了大田马铃薯植株的耐盐性,利用耐盐性综合评价方法有助于耐盐株系的筛选.%This study investigated the morphological and physiological traits of eight transgenic potato (Solanum tuberosum L.) lines carrying AtNHX1 gene and one non-transgenic control "Gannongshu No.2" grown on normal soil and saline land at 0.56％ salt and 0.29％ salt concentration.The salt tolerance of transgenic potato was evaluated using a comprehensive evaluation method including subordinate function,correlation analysis and cluster analysis.The result showed that with the increase of salt concentration the plant height,leaf area expansion rate,yield per plant,chlorophyll content,activity of SOD and the rising range of proline content of transgenic lines were higher 1.17 ～ 3.96 times than that of the control.However,the increasing degree of MDA,relative conductivity of transgenic lines was significant lower than that of control,only 63.07％ ～78.4％ and 82.7％ ～ 86.35％ of the control.A transgenic potato line with highest salt tolerance and three transgenic lines with higher salt tolerance were screened out according to the comprehensive evaluation on the morphological,physiological and biochemical parameters.The transgenic lines with different degree of salt tolerance were as follows:19 ＞ 15 ＞ 8 ＞ 4 ＞ 18 ＞ 2 ＞ 1 ＞ 6 ＞ CK.The result concluded that the salt tolerance of transgenic potato grown in field can be improved by introducing AtNHX1 gene,and the comprehensive evaluation method can be used to screen out transgenic potato with high salt tolerance.