小麦芽期和苗期耐盐鉴定方法的适用性评价

Applicability evaluation of screen methods to identify salt tolerance in wheat at germination and seedling stages

耐盐鉴定是筛选种质和选育耐盐小麦品种的前提。小麦室内耐盐鉴定方法较多,涉及不同生育时期和组织器官。为了评估这些方法在生产上的适用性,本研究选用北方冬麦区5个耐盐品种和5个盐敏感品种为试验材料,对基于芽期和苗期的7种耐盐鉴定方法(涉及27个测试指标)进行实用性评价。结果显示,利用小麦种子的发芽相对盐害率不能区分参试耐盐品种和盐敏感品种,而小麦苗期的叶部盐害指数、根部Na^(+)和K^(+)流速以及根尖数、根径、叶片K^(+)含量的相对盐害率在耐盐和盐敏感品种之间差异显著。综合回归分析结果和可操作性,明确叶部盐害指数是北方冬麦区适用性较高的耐盐鉴定方法,可结合根尖数相对盐害率、叶片K^(+)含量相对盐害率或根部Na^(+)和K^(+)流速用于种质筛选或品种选育。本研究从适用程度方面解析和评价了耐盐鉴定方法,为小麦耐盐育种工作提供参考信息。

Salt tolerance identification is the premise of screening germplasm and breeding salt-tolerant wheat varieties.There are many methods for testing salt tolerance of wheat indoor,involving different growth stages and tissues or organs.In order to evaluate the applicability of these methods in production,we selected five salt-tolerant varieties and five salt-sensitive varieties from the Northern Winter Wheat Production Area of China to compare seven identification methods(involving 27 parameters)for the responses to salt stress of wheat at germination and seedling stages.The results showed that the relative salt-injury rate for germination of grains could not distinguish the tolerant-and sensitive-varieties,while the salt-injury index of leaf,the Na^(+)and K^(+)fluxes of root,and the relative salt-injury rates for root tip number,root diameter as well as leaf K^(+)content of seedlings were significantly different between the tolerant-and sensitive-varieties.Based on the results of regressive analysis and operability,the salt-injury index of leaf was considered to be an appropriate method for identifying salt tolerance that with high applicability in the Northern Winter Wheat Production Area,which can be used for germplasm screening or variety breeding by integrating the relative salt-injury rate for root tip number or leaf K^(+)content,and the Na^(+)or K^(+)flux of root.This study analyzed and evaluated the salt tolerance identification methods from the aspect of application,and provide reference information for salt tolerance breeding in wheat.