不同黄瓜品种苗期耐盐性指标筛选与评价体系构建

为了比较不同黄瓜品种的耐盐性差异，同时构建黄瓜苗期耐盐性筛选的指标评价体系，在日光温室内采用细砂和珍珠岩（2 V∶1 V）混合基质进行育苗，浇灌不同盐浓度的1/2 园试配方营养液，利用黄瓜幼苗叶片盐害指数对15 个黄瓜品种的耐盐性进行聚类分析，并采用主成分分析法分析了黄瓜幼苗各生长指标和生物量指标在耐盐评价体系中所占的比重。结果表明：地下部干质量、壮苗指数和根冠比能较好地反映黄瓜幼苗对盐胁迫的响应，可以作为黄瓜苗期耐盐性的评价指标；依据3 g·L^-1 盐浓度下各黄瓜品种的盐害指数，将供试黄瓜品种分为5 类：耐盐品种（绿冠1 号和宁星欧美水果黄瓜）、较耐盐品种（中农12 号、中科958、荷兰迷你黄瓜、中农21 号和中农16 号）、盐敏感中等品种（津优1 号、优胜和中农8 号）、盐较敏感品种（京棚密刺和新4 号）、盐敏感品种（春棚5 号、绿优和中农大41 号）。

Salt Tolerance Indexes Screening of Different Cucumber Cultivars at Seedling Stage and Construction of Its Evaluation System

This study was conducted to compare differences in salt tolerance of different cucumber（Cucumis sativus L.）cultivars and to construct the measuring system for evaluating identification indexes of salt tolerance in cucumber seedlings．Cucumber seedlings were allowed to grow in substrate
prepared from a mixture of sand and perlite，and then hydrated with half-strength Horticulture nutrient solutions containing different salt concentrations．Cluster analysis was performed to explore the possible similarities in salt-tolerance of 15 tested cucumber cultivars，using data of the leaf salt injury
index．Furthermore，principal components analysis was adopted to measure the proportion taken by each growth-or biomass-index in the salt tolerance evaluation system．The results showed that root dry weight，strong seedling index and the root/shoot ratio could well reflect the cucumberseedlings’response to salt stress，which could also be taken as index for evaluating cucumber seedlings’salt tolerance.Based on this result，cucumber cultivars were separated into 5 groups，i.e.，cucumber cultivars highly resistant to salt-stress（i.e‘Lyuguan No. 1’and‘Ningxingoumeishuiguohuanggua’），cucumber cultivars resistant to salt-stress（i.e.‘Zhongnong No. 12’，‘Zhongke 958’，'Helanminihuanggua’，‘Zhongnong No. 21’and‘ Zhongnong No. 16’），cucumber cultivars relatively sensitive to salt-stress（i.e.‘Jinyou No. 1’，‘Yousheng’and‘Zhongnong No. 8’），cucumber cultivars sensitive to salt-stress（i.e.‘ Jingpengmici’and‘Xin No. 4’）and cucumber cultivars highly sensitive to salt-stress（i.e.‘Chunpeng No. 5’，‘Lyuyou’and‘Zhongnongda No. 41’）．