番茄育种后代Mi抗性基冈植株的筛选

Molecular marker of the Root-knot Nematode Resistance in Tomato

根据已报道的番茄抗根结线虫病Mi基因的CAP标记设计引物,通过微量DNA提取方法提取番茄叶片的DNA.在优化DNA提取方法和PCR反应条件的基础上,对番茄育种后代共306株试材进行抗性标记筛选鉴定。其中264株无PCR扩增产物,即无抗根结线虫病基因位点,其余42株均产生了750 bp的特异片段,即具有抗根结线虫病基因的位点。利用CAP标记,经TaqI酶酶切,有3株产生了570 bp和160 bp二条特异带,为抗性纯合体;8株产生了750 bp,570 bp,160 bp三条特异带,为抗性杂合体。31株不能被TaqI酶消解,只有未消解前750 bp一条带,为感病植株。

The primers of CAP markers with Mi gene in tomato which is resistant to root-knot nematode are reported. DNA from tomato leaves is extracted using a new method of DNA extraction. Based on optimizing PCR reaction and the method of extracting DNA, the resistant marker is selected from 306 samples. Among them 264 samples have no amplified bands, which have no resistant gene site. Other 42 samples produce 750 bp fragment, which have resistant gene site. By CAP marker cleavage with the restriction enzyme TaqI, 3 samples that produce 570 bp, 160 bp bands are homozygous Mi gene plants; 8 samples that produce 750 bp, 570 bp and 160 bp bands are heterozygous Mi gene plants; 31 samples still present 750 bp fragment are susceptible plants.