番茄抗黄化曲叶病毒基因Ty-1的双重SNP标记的开发

本试验旨在开发一种新的设计共显性SNP标记的方法，以提高SNP标记检验的效率，并将其成功应用于番茄抗黄化曲叶病毒基因Ty-1的SNP标记开发中，提高了种质资源鉴定和育种分离世代材料筛选的效率。通过对抗病基因Ty-1和等位感病基因ty-1的cDNA序列进行比对，挑选了两个稳定扩增的多元非同义突变位点，分别用来设计Ty-1和ty-1的SNP标记NL3和NL2，将两个标记进行混合得到双重SNP标记NL2-3。通过用NL2-3检验已知的抗病和感病番茄材料，验证了其多态性和稳定性。并用NL2-3对抗感病材料的F₃代杂交分离群体和普通自交系进行了Ty-1的筛选，并经过田间观察进一步验证了该标记的可靠性。此方法开发得到的双重SNP标记只需要进行一次PCR反应和一次凝胶电泳就可以区分纯合抗、杂合抗、纯合感3种基因型，提高了育种选择的效率。

Double SNP Marker of Ty-1 Alleles in a Co-dominant Manner in Tomato

In this research，a novel method to develop co-dominant SNP markers which was called double SNP markers was developed. This new approach was used to obtain a double SNP marker named NL2-3 of Ty-1 gene resistant to TYLCV（Tomato yellow leaf curl virus）in tomato. The process of developing the NL2-3 double SNP marker included two main steps：Design specific primer pairs of resistant and susceptible genes individually based on two ideal SNP sites and mix the two specific primer pairs in one PCR reaction system with a proper ratio. With SNP marker NL2-3，we identified 5 resistant and 7 susceptible inbred lines and 3 homozygous Ty-1/Ty-1 resistant individuals，11 heterozygous Ty-1/ty-1 ones and 2 homozygous ty-1/ty-1 susceptible lines from F3 segregation population. This result was consistent with the field inoculation assay. We concluded that as the first double SNP marker of Ty-1 gene，NL2-3 can be directly applied to marker-assisted selection and would speed up the screening ofresistant breeding and cultivar evaluation.