小麦禾谷胞囊线虫(Heterodera avenae)的核糖体基因(rDNA)限制性片段长度多态性研究

 采用PCR技术扩增出中国和摩洛哥禾谷胞囊线虫群体的核糖体基因(rDNA)的内转录间隔区(ITS)片段的长度约为1 060 bp。用11种限制性内切酶(RE)酶切禾谷胞囊线虫ITS扩增产物,共产生27个酶切片段。用AluI和RsaI酶切ITS扩增产物证明中国禾谷胞囊线虫ITS属于"B型",而摩洛哥禾谷胞囊线虫ITS属于"A型"。用HinfI酶切后,7个中国禾谷胞囊线虫群体产生2个RFLP片段(860和200 bp),而摩洛哥群体产生3个RFLP片段(520、340和200 bp),HinfI揭示出中国与摩洛哥禾谷胞囊线虫ITS之间存在差异。AvaI和HindⅢ不能酶切禾谷胞囊线虫ITS。用CfoI、Bsh1236I、MsrFI、ScrFI、HaeⅢ和MvaI 6种RE酶切中国和摩洛哥禾谷胞囊线虫群体的rDNA-ITS,均分别得到相同类型的RFLP分布型,因此这6种RE不能揭示中国与摩洛哥群体的rDNA-ITS的差异。

rDNA restriction fragment length polymorphism of Heterodera avenae in China

The amplification of the rDNA ITS region of Heterodera avenae (CCN) from China and Morocco with the current primers AB28 and TW81 yielded one fragment of approximately 1 060 bp. A total 27 scored fragments were obtained with 11 restriction enzymes. Intraspecific polymorphism was revealed within H. avenae by Alu I, Rsa I and Hinf I digestion. Alu I and Rsa I digestion of ITS products of seven Chinese CCN populations yielded 2 fragments respectively (560, 500 bp; 720, 320 bp); but both Alu I ans Rsa I could not digest ITS product of Morocco. Those RFLP profiles revealed by Alu I and Rsa I classified the ITS of Chinese populations as "type B" and Morocco population as "type B"according to Subbotin et.al (2000). Digestion by Alu I also showed heterogenecity in ITS regions of Morocco population, and two additional bands were obtained, the sum of the three fragments was approximately 2 120 bp. Hinf I digested PCR amplified ITS products of Chinese populations obtained 2 fragments (860, 200 bp), but obtained 3 fragments (520, 340, 200 bp) from Morocco population. The results showed that Chinese populations may be distinctly different from Morocco population. Six enzymes Cfo I, Bsh1236 I, MsrF I, ScrF I, Hae III, Mva I, produced restriction profiles identical for all CCN populations. Hind III and Ava I did not digest the ITS products of Chinese and Morocco CCN populations.