Comprehensive Evaluation of Salt Tolerance and Screening Identification Indexes for Three Tree Species | 3个树种苗期耐盐性综合评价及指标筛选

Chinese. 采用盆栽方法,以卫矛、沙枣和美国白蜡实生苗为材料,用不同浓度的NaCl溶液进行处理,对盐胁迫下各树种的形态表现、生理指标响应和矿质元素的变化进行研究。结果表明：在盐胁迫下植物的相对株高生长量和生物量都受到抑制;叶绿素含量随盐浓度的增加而减少;膜透性、丙二醛（MDA）、超氧化物歧化酶（SOD）、脯氨酸和可溶性糖含量均随盐浓度增加而增加;盐胁迫后,Na＋含量在根茎叶中逐渐升高,而K＋在不同部位变化规律有所不同,在根中逐渐减少,在茎中无明显的变化;在叶片中,3个树种的变化规律不完全相同。利用相关分析、主成分分析和隶属函数法,对3个树种的耐盐性进行综合评价：卫矛〉沙枣〉美国白蜡,这与根据盐害症状表现的排序结果相一致。通过灰色关联分析,对14个耐盐评价指标进行筛选,最终筛选出株高相对生长量、膜透性、脯氨酸、根茎叶中的Na＋和K＋含量是与耐盐性评价有重要相关的指标。

English. The morphological characteristics, physiological indexes and mineral elements were investigated with seedlings of Euonymus alantus, Elaeagnus angustifolia and Fraxinus Americana. The seedlings were cultivated in pots that were treated with different NaCl concentrations. The results showed： Under salt stress, the relative height growth and biomass inhibited. The chlorophyll content decreased with increase of the salt concentration. The membrane permeability, MDA, SOD, proline and soluble sugar content of salt-stressed plants increased as the salt concentration increased. Under the salt stress, the Na ＋content of the roots, stems and leaves of plants increased gradually, while the change pattern of K ＋content was different. The K~ content in roots decreased with the NaC1 concentration increased, it in stems had no significant changes, and it in leaves of 3 tree species had differential changes. Salt tolerance of the 3 tree species was comprehensively evaluated with correlation analysis, principal component analysis and subordinative function. The sequence of salt tolerance of the 3 tree species from strong to weak was： E. alantus 〉 E. angustifolia 〉 F. americana. This result was coincided with the sequence ranked in terms of symptoms of salt injury. Screening identification indexes was studied by gray correlation analysis and the results showed that the relative height growth, membrane permeability, proline, Na ＋ and K ＋ contents were important indexes for evaluating salt tolerance of the species.