晋麦47背景回交导入系的遗传选择与性状分析

Genetic Selection and Trait Analysis of Introgression Lines with Jinmai 47 Genetic Background

为深入研究小麦抗旱相关性状的遗传基础，以旱地品种晋麦47为轮回亲本、水地品种鲁麦14为供体亲本构建的导入系（ILs）为材料，在雨养和灌溉两种条件下考察穗下节和穗部农艺性状，利用56对在双亲间表现多态性的SSR标记引物对BC3F4导入系群体的150个株系进行遗传选择，分析筛选后的148个导入系遗传背景及性状相关性。结果表明，ILs群体中有两个株系分别在2个、13个标记位点的基因型不同于双亲，ILs群体的晋麦47基因型回复率迭94．38％。在两种水分条件下ILs群体多数性状表现超双亲，性状变异系数在2．34％～127．11％之间，性状均值偏向轮回亲本晋麦47；ILs群体灌溉条件下的每穗总小穗数（TNs）极显著大于雨养条件下的，与鲁麦14相似。除穗顶部不育小穗数（SST）外，其余性状在两种水分条件下均呈极显著正相关（r=0．221～0．555）。ILs群体穗下节长（FIL）和旗叶叶枕至穗基部长（LPSB）的遗传力均较高，大于0．5975；穗顶部不育小穗数（SST）、穗基部不育小穗数（SSB）的遗传力均较低，小于0．4638，说明小穗结实率易受环境水分条件影响。

The purpose of the present research is to reveal the genetic basis of traits related to drought resistance in wheat. A set of introgression lines （ILs） generated from repeated backcross [（Jinmai 47 × Lu- mai 14） × Jinmai 471 BC3F4 were used as the plant materials, in which Lumai 14 was the donor parent, Jinmai 47 was the recurrent parent, i.e. recipient parent. Seven agronomic traits of ILs and their parents were analyzed under rainfed and well watered conditions. Total of 56 markers selected from 202 SSR markers showing polymorphism between two parents were employed to screening ILs genotype. The results showed that 2 of 150 ILs were detected with 2 and 13 markers loci different from their parents, respectively. The genetic background of Jinmai 47 maintained 94.38% in 148 ILs. Most traits of ILs exhibited transgressive segregation. Coefficients of variation for all traits in ILs ranged from 2.34% to 127.11% under two water regimes. The averages of all traits of ILs presented the tendency to be more adjacent to the recurrent parent Jinmai47. It is similar to Lumai 14 that total number of spikelet per spike （TNS） of ILs under rainfed condition were higher than that under well-watered, which maybe due to the introgression of favorable alleles from the exotic donor parent Lumai 14. All correlation coefficients for ILs traits were significant （r=0. 221-0. 555） between the rained and the well-watered conditions except sterile spikelet number at the spike top （SST）. Heritabilities of the first internode length below spike （FIL） and length from flag leaf pulvinus to spike base （LPSB） were higher （h^2B〉0. 5975）, whereas SST and sterile spikelet number at the spike bottom （SSB） were lower （h^2B0. 4638）. It revealed that seed setting percentage was sensitive to the water conditions.