摘要： 为了明确聚乙二醇(PEG-8000)模拟干旱胁迫对马铃薯组培苗的影响,以11 个马铃薯主栽品种的脱毒组培苗为试验材料,研究比较了在固体培养基中分别添加5%,10%,15%,20%的 PEG-8000模拟干旱胁迫和对照处理下(不含PEG-8000)组培苗生长指标的变化,对供试品种组培苗的株高、最大根长、茎鲜质量、根鲜质量、茎干质量、根干质量和植物水分含量共7 个生长指标进行测定和分析。结果表明,随着胁迫处理PEG-8000浓度的增加,所有材料的组培苗表现出受干旱胁迫现象越严重,当固体培养基中PEG-8000浓度为15%时,11个品种间的差异最大,所测的7 个指标值均显著低于对照,是鉴定马铃薯品种组培苗对干旱胁迫反应的最佳浓度。在该胁迫浓度下,供试马铃薯材料的平均相对根鲜质量为26.9%,变异系数为50.6%,是下降幅度和变异系数最大的一个指标,表明根鲜质量更易受到干旱胁迫的影响。利用6 个相对指标值,对11个马铃薯品种的干旱敏感性进行聚类分析,在欧氏距离为40处,11 个马铃薯品种可分为3 类,Ⅰ 类包括坝薯10号、高原7 号、克新1号和晋薯2号;Ⅱ 类包括中薯2号和中薯20号;Ⅲ 类包括中薯3号、大西洋、夏坡蒂、费乌瑞它和疫不加,3 个类群受干旱胁迫的影响逐渐加重。综合聚类分析和植株含水量的结果,筛选到坝薯10号和高原7号2个耐旱品种。

关键词: 马铃薯, PEG-8000, 干旱胁迫, 生长指标

Abstract: To know the effect of drought stress induced by polyethylene glycol 8000(PEG-8000)on growth indicators of potato plantlets in vitro,eleven main potato varieties in China were evaluated by adding 5%,10%,15% and 20%(W:V)of PEG-8000 to Murashige-Skoog solid medium respectively with do not contain PEG-8000 as the control.Seven characters:plant height,root length,shoot fresh weight,root fresh weight,shoot dry weight,root dry weight and plant water content,were measured and analyzed.The results indicated that all potato plantlets in vitro showed more severe drought stress,when facing with increasing concentration of PEG.Under 15% PEG-8000 stress,the eleven varieties showed the largest differences and all growth indicators were lower than that in control condition,therefore 15%PEG-8000 was the best concentration to simulate drought stress for potato plantlets in vitro.Under such stress,the relative values of indicators were also analyzed,the results showed that the average of relative root fresh weight was 26.9%,was decreased most and had the largest variation coefficient of 50.6%,the relative root fresh weight was the most sensitive to drought stress among all indicators.By clustering analysis,the 11 cultivars were divided into 3 groups at Euclidean distance of 40.The effects induced by drought stress among the three groups are gradually increased:group Ⅰ contains Bashu 10,Gaoyuan 7,Kexin 1 and Jinshu 2;groupⅡcontains Zhongshu 2 and Zhongshu 20;group Ⅲ contains Zhongshu 3,Atlantic,Favorita and Epoka.After clustering analysis and plant water content analysis,Bashu 10 and Gaoyuan 7 could be classified as drought tolerant varieties.

Key words: Potato, PEG-8000, Drought, stress, Growth, indicators

中图分类号: 

• S532.01