摘要
用Ｔｈｉｎｏｐｙｒｕｍｂｅｓａｒａｂｉｃｕｍ（Ｓａｖｕｌ．＆Ｒａｙｓ）Ａ．Ｌｖｅ的基因组ＤＮＡ作探针，分别与大赖草Ｌｅｙｍｕｓｒａｃｅｍｏｓｕｓ（Ｌａｍ．）Ｔｚｖｅｌ．和脆轴偃麦草Ｔｈ．ｊｕｎｃｅｕｍ（Ｓａｖｕｌ．＆Ｒａｙｓ）Ａ．Ｌｖｅ的体细胞杂交，大赖草的１４对染色体均出现杂交信号，脆轴偃麦草只有７对染色体有杂交信号。在用重复ＤＮＡ序列ＰＨｖ６２作探针的原位杂交中，Ｔｈ．ｂｅｓａｒａｂｉｃｕｍ有４对染色体有杂交信号，大赖草有１３对染色体显示杂交信号，新麦草Ｐｓａｔｈｙｒｏｓｔａｃｈｙｓｊｕｎｃｅａ（Ｆｉｓｃｈ．）Ｎｅｖｓｋｉ和脆轴偃麦草无杂交信号。用ＰＨｖ６２作探针的Ｓｏｕｔｈｅｒｎ杂交结果与原位杂交相似。在被检测的１２个普通小麦大赖草异源染色体系中，除二体附加系中５Ｌｒ＃１和双二体附加系１Ｌｒ＃１＋５Ｌｒ＃１没有杂交信号外，其余的异染色体系与ＰＨｖ６２都有特异杂交信号。据此推测Ｔｈ．ｂｅｓａｒａｂｉｃｕｍ有可能参予了赖草属物种的形成过程。但是，大赖草的染色体组在进化过程中显然已发生过变异。
Fluorescence in situ hybridization (FISH) was carried out in somatic cells of Leymus racemosus (Lam.)Tzvel. and Thinopyrum junceum (Savul. & Rayss)A.Lve using Th. bessarabicum (Savul. & Rayss) A.Lve genomic DNA as probe. Fourteen pairs of chromosomes in L.racemosus gave positive signal, and only seven of fourteen pairs of chromosomes in Th. junceum showed signal. In FISH probed with PHv62, the chromosomes in Th. bessarabicum and L. racemosus hybridized with PHv62, whereas Th.bessarabicum showed positive signal in four pairs of chromosomes, and the latter in thirteen pairs of chromosomes. No positive signal was observed in chromosomes of Psathyrostachys juncea (Fisch.) Nevski and Th. junceum. The results of Southern hybridization probed with PHv62 were similar to those of in situ hybridization. Twelve alien chromosome lines of T.aestivum L.racemosus were detected by PHv62 probing. In most of the alien chromosome lines, PHv62 hybridized in fragment of Leymus chromosomes, except for the line containing Leymus chromosomes 5Lr#1 and 1Lr#1. It is inferred that Th. bessarabicum may involve in the formation of Leymus species. Non the less, significant changes have occurred during the evolution of Leymus genomes.
基金
国家攻关项目
863项目
美国麦氏基金
关键词
新麦草
大赖草
原位杂交
SOUTHERN杂交
Thinopyrum bessarabicum, Psathyrostachys juncea, Leymus racemosus, Fluorescence in situ hybridization, Southern blot, Genomic relationship
