陈桂平 张晓东

摘 要：土壤盐渍化是当今农业生产上的重要危害之一，它严重影响当地农作物的生长、发育及产量的提高。为了提高盐碱地的利用效率，该文以蒲公英耐盐突变体 ‘滨蒲1号 及其亲本叶片为材料进行丙二醛（MDA）含量等8种生理指标的测定，同时利用cDNA-RAPD技术对蒲公英耐盐突变体及其亲本根胁迫0、12、24 h的差异表达基因进行分析。结果表明：（1）突变体 ‘滨蒲1号 叶片中脯氨酸含量、叶绿素含量、可溶性蛋白含量、CAT活性、POD活性、SOD活性在不同胁迫时间点均大体高于亲本;MDA含量、相对电导率低于亲本。（2）以筛选出的 10条 RAPD 引物进行cDNA-RAPD分析，共扩增出 22 条清晰的条带，差异条带10条，多态性为45.4%。（3）扩增产物片段大小在150 ～1 000 bp之间，主要为盐抑制基因片段，推测蒲公英耐盐突变体 ‘滨蒲1号 的耐盐性既与渗透调节物质脯氨酸及多种抗氧化酶上升引起的保护作用有关，也与根中一些与耐盐相关的基因表达变化有关。该研究为进一步克隆蒲公英耐盐基因并利用基因工程手段培育耐盐优质的蒲公英新品系奠定一定的理论基础。

关键词：蒲公英，耐盐突变体，生理指标，cDNA-RAPD，差异表达基因

中图分类号：Q943

文献标识码：A

文章编号：1000-3142（2021）09-1417-08

Abstract：Soil salinization is one of main hazards in agricultural production，seriously declining growth，development and yield of local crops. In order to improve utilization efficiency of saline land，salt-tolerant mutant ‘BINPU 1. of Taraxacum mongolicum and its parents were chosen as experimental materials，and eight physiological parameters such as malondialdehyde （MDA）contents were determined，as well as analysis of differentially expressed genes in the root under saline treatments of 0，12 and 24 h through cDNA-RAPD technique. The results were as follows：（1）Except for MDA content and relative conductivity，contents of proline，chlorophyll and soluble protein，and activities of CAT，POD and SOD in leaves of the mutant ‘BINPU 1. under different saline treatments were all higher than those of the parents in general. （2）Totally 22 clear bands were amplified through cDNA-RAPD technique using 10 screened RAPD primers，of which，10 different bands were found and the polymorphism was 45.4%. （3）Fragment size of amplification product ranged from 150 to 1 000 bp，mainly consisting of fragments of salt suppressor genes，indicating that the ability of salt-tolerant mutant ‘BINPU 1. T. mongolicum was related to the protective effects caused by the increase of osmotic regulating substance such as proline and various of antioxidant enzymes activities，as well as some differentially expressed genes in roots. This study provides a theoretical support for further cloning salt-tolerant genes in T. mongolicum and breeding new salt-tolerant T. mongolicum cultivars through genetic engineering.

Key words：Taraxacum mongolicum，salt-tolerant mutant，physiological indexes，cDNA-RAPD，differentially expressed gene

土壤鹽渍化是植物的主要非生物胁迫形式，严重阻碍着农业的发展（张荣梅和马彦军，2017）。近年来随着生态环境的恶化和盲目过量的施用化肥，土壤盐渍化程度在进一步加大，筛选培育耐盐植物是开发利用盐碱地的一种有效方法。近年来植物体细胞耐盐突变体筛选研究已经成为抗盐植物育种学术研究的热点问题。……