以黄早四和Mo17为亲本组配的239个RIL群体,构建了101个SSR标记的遗传图谱,覆盖玉米基因组1 422.7 cM,标记间的平均距离为15.6 cM。以玉米幼胚为外植体、改良N6为基本培养基,对亲本及RIL群体的组培性状进行了评价。采用复合区间作图法在第2、3、5、6、8和9染色体上定位了控制出愈率、Ⅱ型愈伤组织诱导率、绿点及绿苗分化率的8个QTL,并对其遗传效应进行了分析,其基因加性效应能解释相应性状表型方差的4.78%~14.02%。
Inbred lines Huangzao4 and Mo17 were used to develop a population consisted of 239 Recombinant inbred lines(RILs). Based on the F8 generation population, a SSR linkage map was constructed with 101 SSR loci, covering maize genome 1 422.7 cM with an average interval length of 15.6 cM. The 239 RILs and their parental lines were evaluated for tissue cultural traits,including calli initiation frequency, type Ⅱ calli initiation frequency, green buds initiation frequency and plant regeneration frequency. With the method of composite interval mapping, 8 QTLs were identified and located on chromosome 2, 3, 5, 6, 8 and 9. 5 QTLs of regeneration frequency were identified on chromosome 2, 3, 5, 6, and 9, which can explained 6.29%, 5.19%, 7.88%, 14.02% and 10.4% of the phenotypic variance, respectively. 1 QTL on chromosome 5, linked with markers umc1966 was identified with minor effects conferring type Ⅱ calli initiation frequency, which only explained 6.60% of the phenotypic variance. 2 QTLs on chromosome 8, linked with markers bnlg2235 and bnlg240, were identified controlling calli initiation frequency and green buds initiation frequency, which explained 9.51% and 4.78% of the phenotypic variance, respectively. Two QTLs controlling type Ⅱ callus rate and plant regeneration rate were located in the neighboring region of chromsome 8, and these two traits were correlated between each other. However, further study is needed to make clear if the correlation is due to one pleiotropic gene or the linkage of two genes.
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