THE RELATIONSHIP BETWEEN THE CHESTNUT RESISTANCE TO BLIGHT AND AMINO ACID Genetic Variation of Strains of Cryphonectriaparasitica from Korea, USA and China Comparison of Genetic Structures among Cryphonectria parasitica Populations from China,Japan and the USA REVIEW OF CURRENT RESEARCH OF THE WORLD CASTANEA SPECIES AND IMPORTANCE OF GERMPLASM CONSERVATION OF CHINA NATIVE CASTANEA SPECIES Characteristic Analysis and Homology Alignment of EST-SNPs and Candidate Genes for Chestnut Blight Resistance of Castanea mollissima