Functional Characterization Of OsWAX2-3 And OsSCP Genes In Rice

Rice is an important crop that more than half of the world people live on. Abiotic stresses such as drought, heat stress affect rice growth and development to result in serious influence to rice yield and quality. Studies on the stress tolerance related rice genes are important for crop genetic improvement. The function of rice OsWAX2-3 and OsSCP genes were characterized in the studies. The main results are as following:1. Agrobacterium tumefaciens-mediated transformation method was used to transfer OsWAX2-3 gene over-expression and RNAi vectors into rice, transgenic plants were obtained and confirmed at the DNA and RNA levels. The over-expression and RNAi transgenic seedlings are not sensitive to drought,10%PEG,100μmol/L ABA and 100mmol/L NaCl treatments. OsWAX2-3 over-expression plants had shorter stems and spikes and phimosis phenomenon compared to wild type, moreover, cytological structure changes were surveyed in the stems. However, obvious phenotypic changes were not observed in RNAi plants. Seed setting rate,1000-grain weight and photosynthetic performance were not significantly different between transgenic rice and wild type.2. Drought resistance of OsSCP homozygous mutant plants were weaker than wild-type at seedling and booting stage. SOD, POD and CAT activities in mutant and proline content were lower than wild-type, while MDA content of mutant was higher after drought treatment. The leaf water loss rate and electrical conductivity of OsSCP mutant were higher than wild-type. The gene may be related to drought resistance. OsSCP mutant and WT seedlings were not significantly different after 100mmol/L NaCl,100μmol/L ABA and 200mg/L GA3 treatments. Completely loss of OsSCP gene will not have great impact on rice normal growth and development, reproduction and photosynthesis.