野莴苣及其近似种间亲缘关系研究

利用PCR方法对野莴苣及其11种近似种DNA进行扩增,获得ITS、matK和rbcL序列,分析遗传相似系数和聚类分析图谱,探讨野莴苣及其近似种的亲缘关系。通过野莴苣及其近似种ITS序列分析发现:野莴苣和生菜、莴苣、毒莴苣的相似性分别为93.6%、93.1%、92.6%,野莴苣与乳苣的相似性仅为87.8%;matK序列研究发现:野莴苣和生菜、莴苣、毒莴苣的相似性分别为99.2%、99.0%、99.1%,而野莴苣与乳苣的相似性仅为98.3%,结果表明,野莴苣与莴苣属的生菜、莴苣、毒莴苣的亲缘关系更近,与乳苣属的乳苣亲缘关系次之。通过对比rbcL序列发现:野莴苣和生菜相似度达100%,与莴苣、翅果菊、毒莴苣、刺毛莴苣、宿根莴苣的相似度均达99.7%,而野莴苣与乳苣的相似度却为99.4%,将野莴苣归为莴苣属更加合理。

Genetic Comparisons Between Lactuca pulchella (Pursh) DC and Its Closely Related Lettuce Species

The genetic similarity coefficients and cluster analysis maps on Lactuca pulchella (Lp) and its 11 closely related species were obtained by using PCR to amplify ITS,matK and rbcL gene from the total DNA fragments of the lettuce varieties.Based on the ITS sequences,a similarity between Lp and L.sativa var.ramose was found to be 93.6％;betweenLp and L.sativa,93.1％;between Lp and L.serriola,92.6％;and,between Lp and Mulgedium tataricum,the lowest at 87.8％.According to the matK sequences,a similarity between Lp and L.sativa var.ramose was shown to be99.2％;between Lp and L.sativa,99.0％,;between Lp and L.serriol,99.1％;and,between Lp and M.tataricum,98.3％.It appeared that Lpwas related closer to theLactuca species than Mulgedium.By comparing the rbcL,Lp and L.sativa L.var.ramosa had a perfect match with a 100％ similarity;whereas,Lp and L.sativa,L.indica,L.serriola,L.hirsute or L.perennis,at 99.7％;and,Lp and M.tataricum,at 99.4％.Consequently,it was concluded that Lp belonged to the genus Lactuca.