A New Rice Cultivar Wulingjing 1 Resistant to Rice Stripe Virus Developed by Marker Assisted Selection

Rice stripe disease is one of the most serious diseases in rice (Oryza sativa L.) production area in Jiangsu Province, China since 2002. A highly susceptible rice cultivar with excellent food-tasted quality, Wuyujing 3, was improved through the molecular marker-assisted selection in a backcross of Zhendao 88 (with resistance gene Stvb-i). In each backcross generation, the progenies with Stvb-i were selected based on its closely flanking markers. In the advanced backcross generations, marker genotyping of the target gene and visual selection for the phenotype of the recurrent parent were conducted in the selected progeny plants during backcrossing. As a result, a novel cultivar, Wulingjing 1, was fleetingly bred in the BC3F4 generation, whose resistance to the disease was significantly enhanced and the main agronomic traits and characteristics, especially the excellent food-tasted quality were consistent with that of the recurrent parent. In the resistance tests in multiple locations organized by the Seed Management Department of Jiangsu Province, the diseased plant ratio of Wulingjing 1 was only 4.4%, which was significantly lower than that of the recurrent parent (53.2%).

摘 要条纹叶枯病是21世纪以来江苏省最重要的水稻病害之一。食味品质较优的主栽品种武育粳3号因高度感染该病而种植面积锐减。本研究以镇稻88为抗条纹叶枯病毒病基因Stvb-i的供体亲本, 采用回交育种策略, 改良武育粳3号的抗条纹叶枯病性能。在连续回交和自交过程中, 以紧密连锁的双侧分子标记对Stvb-i进行“前景”选择, 同时对后代与轮回亲本遗传背景的相似程度进行分子标记辅助“背景”选择, 在短期内育成抗条纹叶枯病的“武育粳3号”, 命名为“武陵粳1号”。新品种保持了原品种的基本农艺性状、丰产性、稳产性和优异的食味品质, 并大幅度提高了其条纹叶枯病抗性水平, 在江苏省多点抗性鉴定试验中的平均病株率仅为4.4%, 极显著低于原品种(53.2%)。