转苦瓜几丁质酶基因McCHIT1水稻及其稻瘟病抗性  

Transgenic Rice Lines Harboring McCHIT1 Gene from Balsam Pear (Mo-mordica charantia L.) and Their Blast Resistance

作　　者：张长伟[1,2] 凌英华[1] 桑贤春[1] 李平[1] 赵芳明[1] 杨正林[1] 李云峰[1] 方立魁[1] 何光华[1] 

机构地区：[1]西南大学转基因植物与安全控制重庆市重点实验室,重庆400716 [2]四川省农业科学院水稻高粱研究所,四川泸州646000

出　　处：《作物学报》2011年第11期1991-2000,共10页Acta Agronomica Sinica

基　　金：国家转基因生物新品种培育科技重大专项(2008ZX08001-002);重庆市重大攻关项目(CSTC;2010AA1019;CSTC;2010AA1013)资助

摘　　要：稻瘟病是危害水稻的最严重病害之一,探索利用外源基因提高水稻抗稻瘟病水平对现代育种具有重要意义。本研究从T2代起逐代增加抗性选择压,采用苗期人工混合接种和病圃田自然诱发等鉴定方法,对转基因水稻后代进行稻瘟病抗性鉴定和筛选,在T5代获得了7个稻瘟病抗性极显著增强的转McCHIT1基因水稻稳定株系。通过7个生理群26个生理小种的115个稻瘟病有效单孢菌株苗期抗谱测定,这7个株系的抗病频率为52.2%~61.7%,比受体对照缙恢35（36.5%）高15个百分点以上,主要增加了对ZE群生理小种的抗性,提高了对ZG群、ZF群和优势种群ZB群生理小种的抗性。3个株系C36-2-1、C21-6-2、C21-3-1的结实率达80%以上,是丰抗结合较好的转McCHIT1基因株系。McCHIT1基因具有广谱抗性,将其遗传转化水稻,采用＂逐代增加选择压,抗中选抗＂的方法,可筛选出稻瘟病抗性优良、抗谱明显拓宽、产量性状较好的转基因稳定株系。Rice blast is one of the most important diseases damaging rice. It is important to explore a new way of improving blast resistance with introducing exogenous resistance genes in modern breeding. In the study, identification and screening of blast resistance in the transgenic rice offspring were conducted using methods of both seedling nursery artificial inoculation and natural infection in field nursery under the conditions of higher resistance selection pressure increased gradually from T2 generation. Seven stable and outstanding McCHIT1-transforming rice lines with the most significant blast resistance were obtained in T5 generation. Detected with 115 Magnaporthe grisea effective isolates from 26 physiological races belonging to seven groups, the resistance frequencies for the seven lines were 52.2-61.7%, with 15 percentage higher than those （36.5%） for the control Jinhui 35. Compared with the control, these lines increased the resistance to ZE race group, and improved the resistance to the races of group ZG and ZF as well as dominant group ZB. The McCHIT1-transforming rice lines C36-2-1, C21-6-2, and C21-3-1 were the better combination of higher yield and resistance with seed setting rate of over 80%. The McCHIT1 gene is a certain broad-spectrum resistance gene. The disease-resistant lines with both broad-spectrum resistance and better yield traits can be obtained effectively by introducing McCHIT1 gene under gradually increased selection pressure and screening excellent resistance from resistant lines.

关 键 词：转基因水稻 McCHIT1 稻瘟病 抗性 

分 类 号：S511[农业科学—作物学]