摘要
2个选自“水稻×菰”F1杂种的自交 1 8代 (S18)品系整理出多个源自菰的优良特性。然而 ,菰遗传物质渐渗给水稻的直接证据尚缺乏。本文旨在对这 2个优良品系从分子水平上进行分析。将分别提取自 2个系及其水稻和菰亲本的基因组DNA进行 2种内切酶消化后与 1 0个克隆自菰基因组DNA的具多态性的低拷贝或中度重复序列进行Southern杂交。结果表明 ,2个系在 2 0种探针 /酶组合中的限制性片段长度多态性 (RFLP)谱带均相同 ;在其中的 1 8个探针 /酶组合中 ,这 2个系也均与其水稻亲本 (松前 )相同 ;但在其中的 2个探针中 ,2个系明显不同于其水稻亲本 ,表现在有明显来自供体菰的杂交片段 ,而且伴有水稻亲本杂交谱带的丢失。由于这 2个系一直经严格自交保持 ,证明其RFLP谱带的变异是由于菰中DNA渐渗后再经异源重组和 /或相关序列变异所致。
Two S 18 elite lines that were selected from a novel F1 hybrid plant between rice and a perennial wild grass Zizania latifolia (Griseb.) Turcz. ex Stapf exhibited several desirable traits characteristic of the wild donor species Z. latifolia. However, direct evidence for introgression was lacking. The present study was aimed to characterize these two lines by molecular analysis. Genomic DNA of the two lines and of their rice and Z. latifolia parents were isolated and digested with two restriction enzymes. The blots were then probed with 10 diagnostic, low-copy or moderate-repetitive sequences cloned from genomic DNA of Z. latifolia. It was found that RFLP patterns of the two lines were identical in all the 20 probe/enzyme combinations. In 18 combinations, the two lines were also identical with their rice parental cultivar Matsumae. In two probes, however, the two lines differed distinctively from Matsumae, with hybridization fragment(s) apparently from the wild donor species, Z. latifolia. Meanwhile, loss of the rice parental fragment(s) was also observed with these two probes. Since the two lines were maintained by strict selfing, it was concluded that the changed RFLP patterns of the two lines were the result of Z. latifolia DNA introgression, followed by possible non-homologous recombination and/or sequence modification.
出处
《木本植物研究》
CSCD
北大核心
2000年第3期260-263,共4页
基金
ThisworkwassupportedbytheNationalNaturalScienceFoundationofChinaandtheS&TCommissionofJilinProvince
