天津野生稻稻瘟病抗性的遗传分析与抗瘟基因Pi2–1的初步定位

Genetic analysis of the blast resistance in the wild rice species Tianjinyeshengdao and preliminary mapping of the resistance gene Pi2-1

为了更好地揭示天津野生稻对稻瘟病抗性的遗传机理,以天津野生稻与感病品种CO39杂交构建的F2群体为研究对象,利用稻瘟病菌株CHL1743、110–2和318–2进行室内接种鉴定,F2群体的抗感单株分离比符合3∶1,表明其对3个稻瘟病菌株的抗性均由1个主效基因控制,命名为Pi2–1。利用群体分离分析法和隐性群体分离法进行初步定位分析,将Pi2–1基因定位在水稻第6号染色体着丝粒附近的SSR标记AP5659–5到RM7213之间,与2个标记的遗传距离分别为0.9 cM和1.4 cM。

To better understand the genetic basis of blast resistance in the wild rice species Tianjinyeshengdao （TY）, F2 population from the cross between TY and the rice cultivar CO39 which is highly susceptible to blast was constructed and respectively inoculated with isolates CHL 1743, 110-2 and 318-2 in the growth chamber. The results showed that the resistant and susceptible plants in F2 population following inoculation fitted the ratio of 3 ： 1, indicating the resistance to isolates CHL1743, 110-2 and 318-2 in TY was controlled by a single dominant gene which was named as Pi2-1. To preliminary determine the chromosomal location of blast resistance gene, bulked segregant analysis （BSA） and recessive-class analysis （RCA） were conducted. The results indicated that Pi2-1 was located near the centromeric region of rice chromosome 6 and linked to the markers AP5659-5 and RM7213, with a distance of 0.9 cM and 1.4 cM, respectively.