中文摘要：

从60 Co诱变的粳稻中花11M2代中发现了一个白化致死突变体,该突变体从发芽后至3叶期一直表现白化,3叶后逐渐死亡,根据随后的基因定位研究结果,将该白化突变体暂定名为albino lethal 4（abl4）。与野生型相比,abl4突变体的叶绿素含量与类胡萝卜素含量极低,几乎难以检测到。叶绿素荧光分析结果表明,abl4叶片中的电子传递速率和实际光化学效率都为0,而最大光化学效率也极低,显示突变体没有光化学活性。abl4突变体中包括过氧化物酶、超氧化物歧化酶在内的抗氧化酶活性显著升高,过氧化氢酶（CAT）活性显著下降,脂质过氧化产物丙二醛含量显著提高,提示abl4突变体受到氧化胁迫。电子显微镜观察表明abl4不能形成完整的叶绿体,只有类似前质体结构。遗传分析表明,该突变表型受一对隐性核基因控制。利用abl4突变体与籼稻品种龙特甫B杂交获得的F2分离群体进行基因定位,首先将该基因定位于水稻第4条染色体上的SSR标记RM3785和RM303之间。随后,利用新开发的STS和dCAPS标记,进一步将ABL4基因定位在RH46-31和RH46-33之间,物理距离约为201kb。

英文摘要：

An albino lethal mutant, temporarily designated as albino lethal 4（abl4）, was obtained from 60Co γray radiation mutant pool of japonica rice Zhonghua 11. The seedling of abl4 showed albino phenotype from germination to 3leafstage, then died. The chlorophyll and carotenoid contents in abl4 mutant were too low to be detected. Moreover, the electron transport rate and the effective quantum yield of photosystem Ⅱ in abl4 were about zero. On the other hand, the potential photochemical efficiency of PSⅡ in abl4 was also at an undetectably low level, indicating that the activity of photochemical reaction was lost in the leaves of abl4. The activities of antioxidant enzymes induding superoxide dismutase and peroxidase were significantly increased, while catalase was decreased significantly. As results, the content of malondialdehyde was also increased significantly in abl4 compared with the wild type, suggesting that abl4 was strongly subjected to high oxidant stress. Transmission electron microscopy examination showed that abl4 plastids contained some empty vesicles without thylakoids. It was revealed that the phenotype of abl4 was controlled by a single recessive nuclear gene. An F2 population generated by crossing the abl4 mutant with the indica rice cultivar Longtefu B was used for gene mapping,ABL4 was preliminarily located between RM3785 and RM303 on rice chromosome 4 and further mapped to a 201 kb region.