【作者】 龚继平；

【导师】 谢华安；

【作者基本信息】 福建农林大学 ， 作物遗传育种学， 2007， 硕士

【摘要】 水稻种胚的脂肪酶（Lipase）是稻谷储存性脂类水解氧化过程中第一个参与反应的酶，其活性大小是导致稻谷储藏过程中陈化的主要原因之一，种胚脂肪酶活性低可以延缓稻谷的陈化变质，提高水稻品种的耐储藏特性。本研究对两个供试材料PT₄₆（高脂肪酶活性）和WP₂₀（低脂肪酶活性）及其F₂群体，进行脂肪酶活性的定量测定和遗传学分析，并结合SSR分子标记，对控制脂肪酶活性的基因进行了初步定位，最后应用人工老化实验的方法对材料耐储性进行评价。结果如下：1．种胚脂肪酶酶活的精确定量测定与遗传学分析运用脂肪酸比色法定量测定供试双亲及其F₂群体种胚脂肪酶活性，经x²测验，F²群体基因型分布符合1∶2∶1的孟德尔分离比，表明脂肪酶活性高低是由一对单基因控制的，脂肪酶活性低为隐性性状。2．种胚低脂肪酶活性基因的定位以F₂群体为定位群体，结合SSR分子标记，将低脂肪酶活性基因定位在水稻第3染色体上，与SSR标记RM7和RM232之间的遗传距离分别为14.8cM和4.0cM，暂命名为lla（low lipaseactivity）。3．种胚脂肪酶活性与种子耐储性的相关性分析采用人工老化的方法，以种子发芽率和老化指数评价两亲本及其F₂群体的耐储藏特性，结合所测定的脂肪酶活力数据进行相关性分析。结果表明，随着老化时间的延长，脂肪酶活性高的材料，发芽率降低迅速，老化指数增加很快，而脂肪酶活性较低的材料，老化指数变化相对较慢，即脂肪酶活性低的材料较耐储藏。经10、20天处理后的种子老化指数与种胚脂肪酶活性的相关系数分别为r=0.6165^**、r=0.4703^**，说明老化指数和脂肪酶活性呈显著正相关。更多还原

【Abstract】 Being the first enzyme during the lipid hydrolysis and oxidation, lipase was one of the main factor leading to rice aging during rice storage.The low activity of lipase in rice embryos would help alleviate seeds aging and improve the storage stability of rice breed. Based on two parents PT₄₆ which belonging to high lipase activity and WP₂₀ which belonging to low lipase activity,and their F₂ population, this research was carried out by the accurate and genetic analysis of lipase activity.Moreover, the gene for control activity of lipase was mapped with SSR markers. Finally, the significance of rice storability was appraised during artificially accelerating aging experiments.The results were as follows:1. Accurate mensuration and genetic analysis of lipase activity of rice embryos Embryos lipase activity of two parents and their F₂ population was measured with fatty acidcolorimetry method. Based on data of their lipase activity and x² test, the distribution of F₂ genotypes was 1:2: 1 according to Mendelian rules, demonstrated that the activity of lipase was controlled by a single gene and trait of low lipase activity was a recessive trait.2. Mapping of gene for low lipase activity in rice embryosWith F₂ population between PT₄₆ and WP₂₀, the gene of low lipase activity was mapped in the 3rd chromosome of rice by bulk-segregation analysis. Furthermore, the distance was 14.8 cM、4.0cM with marker RM7、RM232, respectively. Therefore, this gene was temporarily designated as lla （low lipase activity） .3. Correlation analysis between lipase activity in embryos and durable storage characteristics of seedsStorability of two parents and their F₂ population were appraised with their grermination rate and aging index by artificially accelerating aging experiments.Correlation analysis was conducted combining aging index and data of their lipase activity. The results showed that seed germination rate of high lipase activity materials was not only decreased rapidly with increasing of aging time,but also their aging index was improved quickly.But the aging index of low lipase activity materials was changed slowly, namely,the low lipase activity materials had better durable storage characteristics. After 10 and 20 days for artificially accelerating aging,the correlation coefficient were r=0.6165** and r=0.4703** between the lipase activity and aging index, respectively.The results demonstrated that stable positive correlation was between aging index and the lipase.更多还原