Gene Expression Analysis Of Tea Leaves In Response To Colletotrichum Kahawae Infection Revealed By CDNA-AFLP

Tea is one of the most popular health drinks in the world. It is not only delicious, but also has antioxidant, diuretic, anti-mutagenic and cardiac spasm functions, which resulting in an increace of tea demand in recent years. In order to effectively control the tea quality and yield, tea disease prevention becomes a more important aspect than before. Tea anthrax(Colletotrichum kahawae) widespread in tea production areas in China, that is affecting the quality and yield of tea seriously. Therefore, it is necessary to study the interaction mechanism between anthrax bacteria and tea plant, the results will provide a theoretical basis for the effective prevention of anthrax on tea plant.Different varieties of tea were inoculated with different strains of Colletotrichum in this study. Tea anthracnose grown in irregular shape, some were round and semi-circular, some were cut by veins, and some spots are connected together into a bigger irregular spot, the infected leaves were curled into a roll under severe infection. The color of anthracnose spot is black, dark brown-based, and some dark green, gradually transformed from a central location to the lesion edges gray, lesion center and dense black specks render bumpy.Different tea varietie has different resistnace level to Colletotrichum infection, Tieguanyin, Rougui and Daye olong are susceptible, Maoxie and Fudingdabaicha are resistant to this disease. This study based on the investigation of anthrax pathogen pathogenicity differentiation morphology, screened the strong pathogenic strains ZRG, less virulent ATG, FSX were selected.The resistant tea variety Maoxie was infected by anthrax pathogen pathogenic strains ZRG, cDNA-AFLP system was then constructed to analyze the gene expression profiles of infected tea leaves. Difference of 146 bands were analyzed and the function were classified, which involved in energy metabolism of carbohydrates (11.6%), lipid metabolism (2.7%), nucleic acid metabolism (6.8%), protein metabolism (15.1%), stress response (21.9%), biological Regulation and Signal Transduction (17.8%), transport (4.8%), cell wall and cytoskeleton metabolism (3.4%) and other metabolic processes (12.3%). Some of the different strips in cDNA-AFLP map were further validated by qRT-PCR. The verification repeat 3 times, the concordance rate was 92.6%, that proved the reliability of cDNA-AFLP system in this study. As a conclusion, the expression of stress-related gene WEKY transcription factors, ethylene transcription factors and peroxidase in tea leaves were up-regulated by Colletotrichum infection.In summary,but their function are not clear, The gene function should be identified by using some transgenic techniques in the near future, that will be laid a foundation for tea anthrax prevention and resistant tea molecular breeding.