高抗白粉病和条锈病小麦-卵穗山羊草衍生后代1003的分子细胞遗传学鉴定

卵穗山羊草中蕴含着许多小麦改良所需的优良基因,是小麦重要的三级基因库。为了解其更多遗传特性,本研究利用细胞学、原位杂交、分子标记、形态学和抗病性鉴定等技术对小麦-卵穗山羊草SY159的衍生后代1003进行鉴定。细胞学鉴定结果表明,1003含有44条染色体,减数第一次分裂中期含有22个二价体且配对良好,减数第一次分裂后期含有44条染色体且均等分离;基因组原位杂交(Genomic in situ hybridization,GISH)分析显示,1003含有42条小麦染色体和2条卵穗山羊草染色体;EST和PLUG分子标记分析表明,导入的染色体属于7M染色体;荧光原位杂交(Fluorescence in situ hybridization,FISH)分析表明,1003中含有38条与中国春标准核型相一致的染色体,4A、5A和7M的FISH信号有变异;苗期抗病性鉴定结果表明,1003对白粉病生理小种E09免疫,对条锈病生理小种条中23(CYR23)高抗;形态学调查表明,1003的农艺性状介于双亲之间,千粒重高于双亲。因此,1003是一个具有白粉病和条锈病抗性的小麦-卵穗山羊草二体异附加系,可为小麦品种改良和抗病育种提供新的种质资源。

Molecular Cytogenetic Identification of a New Wheat-Aegilops geniculata Roth Derived Germplasm 1003 with High Resistance to Powdery Mildew and Stripe Rust

The Ae.geniculata Roth contains many excellent genes for wheat improvement and it is an important tertiary gene bank for wheat. Here,we used cytological,in situ hybridization(Genomic in situ hybridization,GISH and Fluorescence in situ hybridization,FISH) and molecular marker techniques to identify the progeny 1003 of wheat-Ae.geniculata Roth SY159. Cytological observation showed that 1003 contained 44 chromosomes,and the pollen mother cells possessed 22 bivalents with good pairing at metaphase I(PMCs MI),and the pollen mother cells held 44 chromosomes that were equally separated at anaphase I(PMCs AI). GISH analysis showed that 1003 contained 42 wheat chromosomes and 2 Ae.geniculata Roth chromosomes.Molecular marker analysis of expressed sequence tag(EST) and PCR based landmark unique gene(PLUG) indicated that the additions belonged to the 7M chromosome of Ae.geniculata Roth. FISH analysis showed that there were 38 chromosomes in 1003 that were consistent with the standard karyotype of wheat Chinese Spring,while the FISH signals of 4A,5A and 7M were altered. Identification of resistance to powdery mildew showed that 1003 was immune to the powdery mildew physiological race E09. Stripe rust screen indicated that 1003 was high resistant to CYR23 of stripe rust physiological races. Morphological survey showed that the agronomic traits of 1003 were between parents.Therefore,1003 is a wheat-Ae.geniculataRoth disomic addition line with powdery mildew and stripe rust resistance,which will provide new germplasm resources for wheat variety improvement and disease resistance breeding.