抗白粉病小偃麦异代换系的细胞学和RAPD鉴定

利用细胞学和RAPD方法，对从长穗偃麦草与普通小麦复合杂交后代中选育的抗白粉病小麦种质系山农87074－526和山农87074－551进行了鉴定。结果表明，两种质系的根尖细胞染色体数目均为2n=42，花粉母细胞减数分裂中期I（PMC MI）染色体构型为2n=21Ⅱ；二者杂交F1 PMC MI染色体构型亦为2n=21Ⅱ,两种质系分别与小麦中国春的杂种F1 PMC MI染色体构型均为2n=20Ⅱ 2I，说明两种质系为相同的双体异代系。在苗期和成株期两种质系对白粉病15号菌种均表现免疫，其白粉病抗性为显性，并且来自长穗偃麦草，抗白粉病基因位于它们所含的偃麦草染色体上。从80个随机引物中，筛选出2个引物OPE13和OPH15能在两种质系中稳定地扩增出长穗偃麦草亲本的特异DNA片段。

Identification of Tritelytrigia alien substitution line with powdery mildew resistance by cytology and RAPD analysis

Germplasm lines Shandong 87074-526 and Shandong 87074-551 with powdery mildew resistance, which came from the progeny of Elytrigia elongatum (2n = 70) and common wheat,were identified by cytology, RAPD and resistance analysis for powdery mildew. The results are as followed; chromosome numbers of 2 germplasm lines in root tip cell were 2n = 42; chromosome configurations of them and hybrid (F1) between Shandong 87074-526 and Shandong 87074-551 in PMC M I were 2n = 21 II ,and that of F1 between them and Chinese spring in PMC M I was 2n = 20 II +2 I ; Therefore,2 germplasm lines are same alien chromosome substitution line. Them were not infected by No. 15 species caused powdery mildew in seedling and adult stages, and their powdery mildew resistance were proved to be dominance, powdery mildew resistance of 2 germplasm lines came from E. elongatum,and it is controlled by the chromosome of E. elongatum in them. 80 random primers were used for RAPD amplification,the specific DNA frgmment of E. elongatum can be amplified by primer OPE13 and OPH15 in Shandong 87074-526 and Shandong 87074-551.