摘要
经人工授粉和幼胚培养成功地获得了普通小麦“中国春”CS及其phlb突变体CSphlb 与簇毛麦(Haynaldia villosa) 的属间杂种F1, 杂交结实率分别为6.67%和6.25% 。F1 植株的体细胞染色体数2n= 28。育性极差, 自交不结实。F1 植株花粉母细胞(PMC) 减数分裂中期Ⅰ染色体行为观察发现: “CS×H.villosa”F1 平均每PMC仅有1.61条染色体形成二价体和三价体, 平均构型为2n= 28= 26.39I+ 0.79Ⅱ+ 0.007Ⅲ, 染色体交叉数(Xta) 为0.84; “CSph1B×H.villosa”F1 每PMC中有14.45 条染色体发生联会, 形成二价体和多价体平均构型为2n= 28= 13.55Ⅰ+5.95Ⅱ+ 0.55Ⅲ+ 0.222Ⅴ, 染色体交叉数为9.72, 其中56% 以上的PMC具有1～4个多价体(三价体、四价体)。F1 花粉母细胞FISH观察表明: “CS×H. villosa”F1 联会染色体均为小麦染色体(W-W), 在“CSphlb×H. villosa”F1 中有小麦与小麦(W-W)、小麦与簇毛麦(W-H)、簇毛麦与簇毛麦(H—H) 染色体间三种配对类型。这两种类型的杂种F1 再分别与CS、CSphlb 回交, 其结实率分别为6.67% 和0.45% , BC1 植株体细胞染色体数分别为2n= 48和2n= 48～72。BC1 根尖有丝分裂细胞GISH发现, 在“CS×H.villosa×CSphlb”回交BC1 较小群体中, 已获得发生了小麦与簇毛麦染色体罗伯逊易位,以及还?
Hybrids F1 between ph1b mutant (C.S ph1b) of Triticum aestivum var.‘Chinese Spring'(C.S),and Haynadia villosa were obtained by immature embryo culture, with sets of 6 67% and 6 25%, respectively. The analysis of chromosome pairing behaviours at meiotic metaphase Ⅰ showed that on the average, only 1 61 chromosomes could form bivalent and trivalent in each PMC of the hybrid F1 of CS× H.villosa, with the configuration of 2n=28=26 39Ⅰ+0.79Ⅱ+0.007Ⅲ. However, 14 43 associated chromosomes per PMC of the hybrids F1 of CSph1b× H.villosa were involved in bivalents and multivalents, with chromosome configuration of 2n=28=13.55Ⅰ+5.95Ⅱ+0.55Ⅲ+0.22Ⅳ. And over 56% of the PMCs produced 1～4 multivalents (trivalents and quadrivalents). The observation of meiotic chromosome pairing by using genomic fluorescent in situ hybridization (GISH) revealed three types of homoeologous associations: wheat wheat, wheat H.villosa and H villosa H. villosa in PMCs for “CSphlb× H.villosa ”F1 hybrid, and only one type of wheat wheat for “CS× H.villosa ' F1 hybrid. Both F1 hybrids with extremely low fertility were self infertile. The seed set of the backcross of “C S× H.villosa ” with C.S was 6.67% and that of “C.S phlb× H.villosa ' with C.S or C.S phlb was only 0.45%. The chromosome number of BC1 plants varied from 48 to 72. Robertsonian translocation chromosomes consisting of chromosome arms from wheat and H.villosa were detected by mitosis GISH in the BC1 plants from the backcross of C.Sphlb× H.villosa to C.S phlb. It also showed that chromosomes fragment translocation probably occurred between common wheat and H villosa . These results showed that phlb gene strongly induced homologous chromosome pairing between common wheat by direct genetic transfer using phlb gene.
出处
《西南农业学报》
CSCD
北大核心
1999年第S2期97-104,共8页
Southwest China Journal of Agricultural Sciences
基金
中国科学院资助
四川省科学技术委员会资助
中科院成都地奥科学基金!(DASF)
