鲜食型甜玉米叶片叶绿素含量的遗传分析

Genetic analysis on chlorophyll content of leaf in fresh-eatable sweet corn

以8个甜玉米亲本为研究对象,采用Griffing双列杂交法Ⅱ,对玉米叶片叶绿素含量的遗传特性进行了系统分析。结果表明,8个自交系叶绿素含量的一般配合力(GCA)值为T1>T33>T8>T3>T7>T5>T4>T14,其中T1、T8和T33叶绿素含量的GCA较高,可以提高杂交组合的叶绿素含量,但特殊配合力存在明显的组合差异。自交系利用价值的综合评价表明,T8和T33是选育叶片高叶绿素含量的理想亲本。玉米叶片叶绿素含量性状的遗传符合加性-显性-上位性模型,以基因非加性效应为主,存在着显著的显性与上位性效应;控制玉米叶绿素含量遗传增效等位基因为隐性。广义遗传率为63.92%,狭义遗传率为15.90%。可见,在高光效育种工作中,对叶绿素含量选择宜在高代进行,同时利用叶绿素含量高的自交系作为亲本并广泛测配有利于叶片高叶绿素杂交种选育。

Chlorophyll content of corn leaf is a significant trait for high photosynthetic efficiency production and stay-green. In this paper, a synthetical heredity analysis was provided for chlorophyll content based on the Griffing diallel design for 8 inbred lines of sweet corn. As a result, the order of chlorophyll content GCA （general combining ability） value was T1 〉T33 〉T8〉T3〉T7〉T5〉T4〉T14. The results showed that inbred lines T1, T8 and T33 had the higher chlorophyll GCA value than the other five inbred lines, therefore, it is possible to in- crease chlorophyll content in their progenies. However, special combining ability （SCA） significantly varied among combinations in chlorophyll content. A comprehensive evaluation of the utilization value of the inbreds showed that T8 and T33 were the excellent inbred lines on high chlorophyll content of corn leaf in breeding prac- tice. The inheritance of chlorophyll content was in agreement with the additive-dominance-epitasis model. Fur- thermore, compared with additive genetic effect, dominant and epistemic genetic effect played a more important role in the chlorophyll content inheritance in corn. The alleles increasing chlorophyll content were recessive. The generalized heritability and narrow heritability of chlorophyll content was 63.92% and 15.90%, respectively. In conclusion, this characteristic should be used for selection in the high generations in the high phot.osynthetic effi- ciency breeding, and inbred lines with high chlorophyll content being widely crossed might be useful in inbreed- ing of hybrid with chlorophyll content in corn.