【作者】 邓云；

【导师】 周元昌； 吴为人；

【作者基本信息】 福建农林大学 ， 作物遗传育种， 2007， 硕士

【摘要】 水稻细菌性条斑病（简称细条病）是中国南方水稻上的一种常见病害，现已经成为影响我国水稻生产的主要病害之一。控制病害流行、减少生产损失，开发和利用水稻本身的抗病性，培育抗病品种，是从根本上解决病害问题的有效途径。本研究在前人工作的基础上，对控制水稻细条病的一个QTL，qBlsr5a进行了精细定位，主要结果如下：1、从高抗细条病品种Acc8558（供体亲本）与高感细条病品种H359（受体亲本）杂交及连续多次回交的后代材料中选出了两个遗传背景与受体亲本相似，只在一个细条病抗性QTL（qBlsr5a或qBlsr3d）上含有来自供体亲本抗病等位基因的近等基因系，分别记为H359-BLSR5a和H359-BLSR3d。接菌鉴定表明，两近等基因系与H359间的细条病抗性差异显著，证明了这两个抗性QTL的真实存在。2、将近等基因系H359-BLSR5a和H359-BLSR3d分别与H359杂交并自交，获得了分别含2265个单株和1913个单株的F₂分离群体。对两个F₂群体进行抗病性接菌鉴定，以病斑长度为指标，结果显示qBlsr3d和qBlsr5a对抗病性的表型变异的贡献率分别为20.68％和43.73％。3、从RM153和RM413之间（遗传图距为18.4cM）挑选出12个SSR标记，检测它们在H359-BLSR5a与H359间的多态性，共筛选到6个多态标记，分别为RM17734，RM5816，RM122，RM159，RM7029，RM6317。4、从H359-BLSR5a×H359的F₂群体中选出极端抗病个体120株，用筛选出的8个SSR标记分析这些极端抗病个体，用Mapmaker／Exp3.0软件构建局部分子标记连锁图，将qBlsr5a定位于SSR标记RM153和RM17734之间，与RM153和RM17734间的距离分别为0.4cM和0.7cM。更多还原

【Abstract】 Bacterial leaf steak （BLS） has become a familiar epidemic rice disease, and caused serious yield loss in south China. It is dedirable to exploit the rice germplasm against bacterial leaf steak to improve the level of disease resistance of rice hybrids. Based on the research of formers, this study focused on the fine mapping of a resistance QTL of BLS, qBlsr5a. The main results are as follows:1 Donor parent Acc8558 （high resistant to BLS） and recipient parent H359 （high infectious to BLS） were used as material to develop two near-isogenic lines H359-BLSR5a and H359-BLSR3d, both of them contained one resistance QTL （qBlsr5a or qBlsr3d）. Results of strain bacterium experiment showed that resistance to BLS of the two near-isogenic lines were significantly different from H359, and proved that the disease resistance QTLs （qBlsr5a and qBlsr3d） truely exists.2 Using H359-BLSR5a and H359-BLSR3d as parents crossed with H359 respectively to develope two F₂ populations comprising 2265 and 1913 plants. Resistance analysis of the F₂ populations indicated that the qBlsr3d and qBlsr5a could respectively explain 20.68% and 43.73% of resistance phenotypic variance.3 12 SSR markers between RM153 and RM413 （18.4 cM genetic map ） was choosed to analyze its’ polumorphism between H359-BLSR5a and H359. 6 polumorphic makers, RM17734, RM5816, RM122, RM159, RM7029 and RM6317, were obtained.4 120 plants with high resistance to BLS from the F₂ population of H359-BLSR5a x H359 were selected to constructe a molecular map of 8 SSR markers by using Mapmaker/Exp 3.0 program. From the map, the QTL qBlsr5a was located between RM153 and RM17734, 0.4cM away from RM153 marker and 0.7cM away from RM17734 marker.更多还原