NaCl胁迫对不同西瓜种质资源发芽的影响

Effect of NaCl Stress on Germination of Different Watermelon Varieties

采用7种NaCl浓度胁迫对23份纯合的西瓜种质资源进行耐盐性研究。结果表明:随着NaCl浓度增加,西瓜发芽率下降,不同种质资源的致死浓度有明显差异,在低浓度下大部分种质资源发芽率不变或反而增加。在80～160mmol/L盐浓度下,千粒重与发芽率呈显著性相关,最大相关系数为0.606。相同NaCl浓度对不同西瓜种质资源间的侧根、根长、鲜重、下胚轴和盐害指数影响不同。对5项测定指标进行聚类分析,将23份种质资源分为4类,第2类为耐盐性好的材料,综合分析四倍体西瓜的耐盐性高于二倍体。

In order to screen watermelon varieties in salt tolerance, germination experiments of 23 genotype watermelon varieties were done in 7 NaCl concentration. The results showed germination rate decreased with the NaCl concentration increasing and in mostly varieties were equal or increased comparing with those treated in 40-80mmol/L. Under 80-160mmol/L NaCl stress, the significant correlation was existed between 1000-grain weight and germination rate, among which the largest correlation coefficient was 0.606. Effects of the same NaCl concentration on the lateral root numbers, root length, root fresh weight, hypocotyls length and salinity injure index among different watermelon varieties were different, and the results indicated that the tetraploid watermelon possessed higher salt tolerance than diploid. By the dendrogram of cluster analysis according to 5 principal components （germination rate, lateral root, et al）, 23 varieties were affiliated with 4 clusters and the second cluster were identified to be best and salt tolerance of 6 varieties were better.