小麦抗白粉病新基因的鉴定及其分子标记研究

Powdery mildew is one of bad disease to attack wheat. Using powdery mildew resistance genes to breed resistant varieties is the most economical and effective approach to control the disease. So, It is an important task to identify new resistance genes and create new germplasms with resistance to powdery mildew continually as well as to enhance their genetic diversity in hereditary improvement of wheat. Thinopyrum intermedium (2n=42) and Thinopyrum Ponticum (2n=70) are related species of wheat. They have many useful traits such as resistance to many wheat disease (e.g. powdery mildew, rust, yellow dwart virus and streat mosaic virus). Therefore, they are very valuable related species of wheat in hereditary improvement of wheat. So far, there is still no report about transferring the resistance gene to powdery mildew from Th. intermedium and Th. Ponticum to wheat. So, identifying resistance genes to powdery mildew in them and transferring the genes into wheat are very important for extending hereditary basis of disease resistance to powdery mildew in wheat..In this study, 4 partical amphiploids (8x), one of them is immune to powdery mildew, 4 disomic aliem addition lines, 3 monosomic alien addition lines, 2 disomic alien substitution lines, 2 alien translocation lines and 8 germplasms with good agronomic traits, all of them have good resistance to powdery mildew, were obtained from the progenies of Th. intermedium and Th. Ponticum crossed with common wheat. They are valuable materials in hereditary improvement and genetic research of wheat. Using the methods of molecular cytogenetic and disease resistance identification, resistance genes to powdery mildew in these materials were locatized on chomosome of E genome of Th. Intermedium. It was proved that is a new resistance gene to powdery mildew by disease resistance identification and inference. SSR and RAPD analysis were made in some of germplasms lines with resistance to powdery mildew, and the markers of SSR and RAPD which are linked to powdery mildew resistance gene were set up.

本项目将对普通小麦与偃麦草杂交所获得的抗白粉病种质首先进行原位杂交和白粉病分小种鉴定，确定抗病新基因的类别。然后利用抗病种质与感病品种杂交，根据F1及F2代的抗性表现，分析抗病基因的性质和数目，并利用F2代分离群体将抗病基因定位到具体的染色体位点上，找到与其连锁的分子标记。