Abstract: To determine the heterosis and genetic effects of maize deep-seeding tolerance-related traits. 22 F₁ hybrids and 22 parents with different deep-seeding tolerance were used as materials to analyze the heterosis, genetic effect, and combining ability of 13 deep-seeding tolerance-related traits by ADM (additive-dominance-maternal effect genetic model) under 3, 15, and 20 cm depths in this study. It was found that: with the increase of sowing depths, seeding emergence rate (RAT), seedling length (SDL), root length (RL), mesocotyl coarse (MESC), and root weight (RW) of parents and F₁ were decreased, however, mesocotyl length (MESL), coleoptile length (COLL), mesocotyl and coleoptile total length (MESL+COLL), mesocotyl length: coleoptile length ratio (MESL/COLL), coleoptile coarse (COLC), seedling weight (SDW), mesocotyl weight (MESW), and coleoptile weight (COLW) were increased; The Pearson correlation and PCA (principal component analysis) showed that the synergies or antagonisms of among 13 traits formed the response mechanism of maize deep-seeding tolerance. The 13 traits displayed obviously, F₁ heterosis index were 90.97%~175.64%; Except for MESL/COLL and COLW, other traits showed positive mid-parent and over-parent heterosis. Thus, to improve maize breeding efficiency, it is necessary to pay attention to the selection of main basic materials, namely high-parent, middle-parent, and female-parent, as well as the influence of heterosis should be considered. The additive genetic effect of MESL, COLL, MES+COLL, MESL/COLL, and RL were predominated, these traits could be modified in early generations by simple backcross or single cross recombination; Other traits displayed additive and dominance main effects, and interaction effects with environment, these traits could be modified at specific sowing depths to reflect their heterosis. The general and special combining abilities of parents and F₁ in 13 traits had significant differences, 8802A male-parent with good comprehensive additive effect value was screened, H21×8802A progeny may have the potent to improve and develop some elite deep-seeding tolerant maize materials. The study would be helpful for maize deep-seeding tolerance breeding.

Key words: maize, deep-seeding tolerance, heterosis, genetic effect, combining ability

摘要： 为确定玉米耐深播性状的杂种优势表现及遗传规律,本研究以耐深播性不同的22份亲本及组配的22份F₁杂交种为试材,在3、15和20 cm播深下,采用加性-显性-母体遗传模型(ADM)分析了13个耐深播性状的杂种优势、遗传效应及配合力大小。结果表明,随播深增加玉米亲本和F₁的出苗率、苗长、根长、中胚轴粗及根重降低,而中胚轴长、胚芽鞘长、中胚轴与胚芽鞘和、中胚轴与胚芽鞘比、胚芽鞘粗、苗重、中胚轴重及胚芽鞘重升高;Pearson和主成分分析(PCA)表明,这13个性状间的协同或拮抗作用形成了玉米耐深播响应机制。13个耐深播性状的杂交优势表现明显,F₁杂种优势指数介于90.97%~175.64%;除中胚轴与胚芽鞘比、胚芽鞘重外,其余性状均表现为正向中亲和超亲优势。因此培育耐深播玉米品种时不仅需要注重对高亲、中亲及母本等主要基础材料的选择,还需兼顾杂种优势的影响,以提高育种选择效率。中胚轴长、胚芽鞘长、中胚轴与胚芽鞘和、中胚轴与胚芽鞘比及根长的加性遗传效应占主导地位,育种上可用简单回交法或单交重组法在早代对这些性状进行遗传改良;其余性状同时受加性与显性遗传主效应及其与环境互作效应的调控,这些性状最好在特定播深环境下进行遗传改良,以充分发挥其在特定环境下的杂种优势。13个耐深播性状的双亲一般配合力(GCA)及F₁特殊配合力(SCA)间均差异显著,筛选出1份综合加性效应值良好的父本8802A,推测利用优良H21×8802A后代能改良创制一些优良耐深播玉米材料。本研究为玉米耐深播新品种培育奠定了理论基础。

关键词: 玉米, 耐深播性, 杂种优势, 遗传效应, 配合力