八份源于同一群体的玉米自选系配合力研究

Combining Ability of Eight Maize Inbred Lines from the Same Population

为拓宽玉米种质遗传基础,本研究以美国地域性近缘品种杂交组建的基础群体经3轮改良选育出的8份自交系为被测系,以美国自交系PH6WC和PH4CV及欧洲自交系9F592和6F576为测验种,以先玉335和德美亚3号为对照,采用NCⅡ遗传交配设计,对8个自交系的产量性状遗传力及配合力进行研究,分析其潜在利用价值。结果表明:所选育的自交系SK1、SK3、SK5和SK6的GCA效应值较高,受环境变异影响较小,有直接利用组配杂交组合或改良利用的价值;经过对32份杂交组合产量性状SCA与对照相比较,被测系与欧系的杂交组合9F592/SK6、6F576/SK3、9F592/SK5的SCA效应值在整体组合中占前三位,PH4CV/SK1、PH6WC/SK4的SCA效应值也较高,在整体组合中分别占前4、5位,表明地域性近缘玉米品种间杂交组建群选系,尽管血缘背景复杂,与地理近缘系组配也能筛选出优良组合,但是与地理远源系组配强优势杂交组合的几率要更高、组合的优势要更强。同时也说明了利用地域性近缘优良玉米品种间杂交组建群体,在一定程度上能够达到扩充种质遗传基础的目的,从中选育优良自交系是可行的,并可建立地域性近缘品种杂交群体选系×地理远源系的杂优模式,提高选育强优势杂交组合的几率。

In order to broaden the genetic basis of maize germplasm,eight inbred lines were selected from the basic population of the cross of American regional close relatives after three rounds of improvement.American inbred lines PH6WC and PH4CV,and European inbred lines 9F592 and 6F576 were used as test materials.Xianyu 335 and Demeiya 3 were used as controls.We used NCⅡdesign to study the heritability and conbining ability of yield traits of 8 inbred lines and analyzed their potential value.The results showed that SK1,SK3,SK5 and SK6 bred from region nearly cultivar population had higher GCA habitability and less affected by environmental variability could be used to assort hybrid combinations or improve other materials.By comparing the yield traits SCA between 32 hybrids and check cultivar,it was found that the 8 inbred lines had more hybrid advantage combinations with European inbred lines than American inbred lines,among 32 combinations,the yield hybrid advantage SCA of 9F592/SK6,6F576/SK3 and 9F592/SK5 were the top three,and next two were PH4CV/SK1 and PH6WC/SK4.We could get the conclusion that,inbred lines developed from population established by region nearly cultivar had higher probability of choosing heterosis hybrid combinations and better combination with region distance inbred lines than with inbred lines region nearly.At the same time,establish population by region nearly cultivar could expand germplasm resources,develop inbred lines,and establish new heterosis model:inbred lines developed from region nearly cultivar population×region distance inbred lines.