刺槐家系耐盐性状的变异、相关分析及选择

①根据对不同盐浓度处理下刺槐家系苗高、地径及它们的绝对和相对生长量的调查分析,得出短期盐胁迫下苗高绝对生长量及其相对生长量能灵敏反映出苗木受盐害的程度,其它指标用于评价苗期耐盐性的效果较差.②根据对盐胁迫下40个刺槐家系各生长性状的调查分析,研究了它们的遗传变异,并用指数选择法对刺槐家系进行了选择.结果表明:刺槐家系的各耐盐性状受较大程度的遗传控制,环境效应影响较小,通过选择可望取得明显遗传进展;指数选择在刺槐家系多性状综合选择时有较好效果,对各约束性状的控制也可达到预期目的.③根据对盐胁迫下6个刺槐家系盆栽苗的苗高、苗高绝对生长量、苗高相对生长量、水势、电导率和叶部钾钠比的调查分析,研究了它们的遗传变异、各性状间的相关关系和它们对苗高的通径分析.结果表明:苗高和苗高绝对生长量之间相关性非常紧密(r=0.700),与苗高相对生长量之间相关性一般(r=0.451),苗高绝对生长量与苗高相对生长量遗传相关略高(r=0.635),苗木水势和质外体电导率与苗高的表型和遗传相关均表现适度的负相关;苗高生长主要受苗高绝对生长量的直接效应的影响,直接通径系数次序为苗高绝对生长量、钾钠比、水势、电导率和苗高相对生长量,苗高相对生长量、钾钠比、水势和电导率通过对苗高绝对生长量间接效应来影响苗高的生长.

Studies on genetic variation, correlation and selection of salinity tolerance traits of Robinia pseudoacacia families.

The growth traits were investigated on 1 year old Robinia pseudoacacia seedlings under different salt stresses. Results show that the absolute stem height growth and the relative stem height growth were fit for estimating the salinity tolerance of Robinia pseudoacacia. ②Each growth trait was investigated on 1 year old seedlings of 40 Robinia pseudoacacia families growing in containers under salt stress. The multi selection index method was employed in multi traits selection for Robinia pseudoacacia families in studing their genetic variation. Results show that: the salinity tolerance traits were under strong genetic control between Robinia pseudoacacia families. The environment domino effect is small. It is possible to obtain an obvious genetic improvement. The efficiency of multi select index method was good in multi traits selection. It also achieved the expected object to control on each restrict traits. ③Stem height, relative stem height growth, water potential, conductance ratio and K +/Na + were investigated on 1 year old seedlings of 6 Robinia pseudoacacia families under salt stresses. Their genetic variation, correlation and pathway analysis were studied. The results show that:the salinity tolerance traits (except K +/Na +) were under strong genetic control between Robinia pseudoacacia families. The environment domino effect is small. It is possible to obtain an obvious genetic improvement. Absolute stem height growth showed high genetic correlation with stem height( r =0.700). The genetic correlation between stem height and relative stem height growth was small( r =0.451). It was stronger between absolute stem height and relative stem height growth( r =0.635). Water potential and conductance ratio showed high phenotypic and negative genetic correlations with stem height. Stem height was mostly affected by the direct effect of absolute stem height growth. The sequence of direct pathway coefficients was absolute stem height, K +/Na +, water potential, conductance ratio and relative stem height growth. Relative stem height growth, water potential, conductance ratio and K +/Na + affected stem height by the indirect effects with absolute stem height growth.