小麦重组自交系群体9个重要农艺性状的遗传分析

为了初步判断小麦重要性状的遗传组成,并筛选适于QTL定位的性状,以小偃81和西农1376及其构建的重组自交系群体(RILs)F7代为材料,采用植物数量性状主基因+多基因混合遗传模型研究了株高、叶面积、穗下茎长、穗下节长、穗下节间直径、穗长、小穗数、穗粒数和抽穗期等9个重要农艺性状的遗传特点.结果表明,穗下节长性状符合多基因遗传,无主基因存在;株高、小穗数、穗粒数、叶面积、穗长和抽穗期6个性状符合2对主基因+多基因遗传;穗下节间直径性状符合3对主基因遗传,无多基因存在;穗下茎长性状则符合3对主基因+多基因遗传.株高、穗长、抽穗期和穗下节间直径等4个性状的主基因遗传率分别为82.32％、75.75％、81.98％和91.04％,可能含有较大的主效QTL.

Genetics Analysis of Nine Important Agronomic Traits in Wheat Population of Recombinant Inbred Lines

In order to estimate the genetic composition of traits, formulate relevant breeding program and choose traits suit for QTL mapping. The genetic analysis on plant height, leaf area, ear stem, the top 1st internode length (TIL), upmost internode diameter (UID), spike length, spikelet number, grain number per spike and heading date were conducted in a population of F₇ derived recombinant inbred lines (RILs) from a cross of Xiaoyan81×Xinong1376 by using the mixed inheritance model of major genes and polygenes of the quantitative traits in plant. The main results were as follows: the trait of the top 1st internode length (TIL) was controlled only by polygenes; the traits of plant height, spikelet number, grain number per spike, leaf area, spike length and heading date were controlled by two pairs of major genes and polygenes, the trait of upmost internode diameter (UID) was controlled only by three pairs of major genes, and the trait of ear stem was controlled by three pairs of major genes and polygenes. The heritability of major genes of plant height, spike length, heading date, and upmost internode diameter were 82.32%, 75.75%, 81.98% and 91.04%. They may be controlled by main QTLs.