抗条锈病小偃麦异附加系及其染色体稳定性的研究

Transfer of Stripe Rust-Resistance from Agropyron Intermedium to Triticum aestivum and Stability of Alien Chromosome(s)

以异源八倍体小偃麦中4作为抗条锈病染色体的供体亲本,以普通小麦品种铭贤169作为受体亲本,通过杂交、回交、自交、抗病性鉴定和花粉母细胞减数分裂染色体显微镜检查,选择出了含抗条锈病中间偃麦草染色体的二体附加系;对附加系花粉母细胞减数分裂观察发现,终变期有5.2%的细胞中出现了单价体,后期Ⅰ中有7.4%的细胞中存在停留于赤道板上不分离的染色体,表明附加的染色体在一定程度上是不稳定的;所得到的3个附加系中的1个,其组织病理学特征与另外两个明显不同,推测这3个附加系所附加的中间偃麦草染色体并非是同一个。

The chromosome(s)of Agropyron intermedium which confer the resistance to Puccinia striiformis have been transferred to a universal susceptible cultivar of Triticum aestivum.In 5.2% of mi- crosporocytes of a disomic addition line(DAL)the alien chromosome were in monovalent form.and in 7.4% of microsporocytes the alien chromosome lagged at first anaphase,implying the incomplete stability of the addition lines.The pathologically histological observation on the leaves inoculated with urediospores of P.striiformis showed that the pathogen failed to establish its colony in one of the three DALs,while the pathogen formed colonies fairly in the other two DALs.but yet was confined to a few cells immediately around a site of invasion.The observation suggests the speculation that the DALs involved two types of resistant genes harbored in separate chromosomes of Agropyron intermedium.