耐低磷玉米自交系根系性状的主基因+多基因遗传分析

摘要

At present,evaluation the ability of maize inbred lines resistant to low phosphorus lack of unified indicators,in order to proven genetic mechanisms of resistance under low phosphorus corn seedling root traits,providing theory basis screen to low phosphorus tolerance maize inbred lines and hybrid breeding to the major gene and polygenic inheritance model was applied to study the genetic mechanisms of root characteristics at seedling stage.The results showed that the total root lengths were dominated by additive-dominant-epistemic gene and select the most efficiency in the F2,but the environment had a greater influence;Root volume was dominated by two pairs of additive-dominantepistemic major gene-+-additive-dominant polygenic control,the interactions effects between major genetic and dominant effect genes for the negative effects,select the most efficiency in the B2,Root surface area was dominated by two pairs additive-dominant-epistemic major gene+dominant polygenic,the major dominant genes effect had a negative effect on the root surface area,had a positive role in the gene additive effect,and select the most efficiency in the F2,Root surface area and root volume had less affected by the environment.%目前对玉米自交系耐低磷能力评价缺乏统一的指标,为探明耐低磷玉米苗期根性状的遗传机制,为耐低磷玉米自交系的筛选及杂交种选育提供理论支撑,利用主基因+多基因遗传模型,研究了玉米自交系及其杂交和回交世代苗期根系性状的遗传机制.结果表明,总根长受加性-显性-上位多基因控制,在F2世代筛选效率最高,环境对其影响较大;根体积受2对加性-显性-上位性主基因+加性-显性多基因控制,主基因间存在互作效应,主基因显性效应为负效应,在B2世代筛选效率最高,受环境影响较小;根表面积的遗传受2对加性-显性-上位性主基因+多基因控制,主基因显性效应对根表面积起负向作用,主基因加性效应起正向作用,在F2代筛选效率最高,受环境影响较小.