玉米苗期耐盐性鉴定技术研究及耐盐自交系筛选

Research on Salt Tolerance Identification Technique and Salt Tolerance Inbred Lines Screening of Maize Seedling

土壤盐碱化使耕地利用率降低,作物生产受到限制。玉米耐盐种质的鉴定及筛选在盐碱地改良利用中具有重要意义和应用前景。本研究为筛选玉米苗期耐盐鉴定的最适NaCl浓度,选取16份代表性自交系进行0(对照)、100、150、200、250、300 mmol/L NaCl处理7 d,测定株高、根长、地上部鲜重、地下部鲜重、地上部干重和地下部干重6个指标,并记录苗情。结果表明,盐处理7 d后,与对照相比,150 mmol/L NaCl处理的各指标存在显著差异,并且比其他盐浓度处理的变异系数更大,由此确定150 mmol/L为玉米自交系苗期耐盐鉴定的最适浓度。据此本研究建立了玉米苗期150 mmol/L NaCl处理的多指标综合评价耐盐鉴定技术。利用该技术对76份玉米自交系进行分析,通过加权隶属函数法计算耐盐综合评价指数D并聚类分析,将76份玉米自交系划分为高耐盐、耐盐、盐敏感及盐高敏4个类群,其中明71、中106、四-287和8112苗期耐盐能力较强,可作为玉米耐盐育种的优异资源;地上部鲜重耐盐系数与D值相关性最高,可作为玉米自交系苗期耐盐性评价的主要指标。

Soil salinization and alkalization reduce the usability of arable land and impair crop production.Identifying and selecting maize germplasm showing salt-tolerant is of significant importance in the reclamation and utilization of saline-alkali land.To determine the optimal NaCl concentration for screening salt tolerance in maize seedlings,16 representative inbred lines were treated with 0(control),100,150,200,250,and 300 mmol/L NaCl solutions for seven days.Six indicators,including shoot height,root length,shoot fresh weight,root fresh weight,shoot dry weight and root dry weight,were measured,along with recording the seedling conditions.The results showed that after seven days of salt treatment,significant differences were observed in all indices under 150 mmol/L compared with the control,and the coefficient of variation was greater than at other salt concentrations.Therefore,150 mmol/L was identified as the optimal concentration for salt tolerance identification in maize inbred lines,and a salt tolerance identification technology was developed.Using this technology,76 maize inbred lines were analyzed,and a comprehensive salt tolerance evaluation index(D)was calculated using the weighted subordinate function method and cluster analysis.The 76 lines were categorized into four groups:high salt tolerance,salt tolerance,salt sensitivity,and high salt susceptibility.Among them,the inbred lines Ming71,Zhong106,Si-287,and 8112 showed the strongest salt tolerance,serving as valuable resources for salt tolerance maize breeding.The salt tolerance coefficient of the fresh weight of the above-ground tissues showed the highest correction with the D value and could be used as the primary indicator for evaluating salt tolerance in maize inbred lines during the seedling stage.