The Ecological Characteristics Of Marine Fungi Of Cage Culture Area In Daya Bay

Annual investigation of fungi in Dongsheng marine cage culture areas at Daya Bay was carried out from April 2010 to February 2011. Seawater and sediments were sampled in 3 sites in Dongsheng cage culture area and 3 sites in Xiaolajia, the control, every quarter to investigate chemical and physical factors and fungi numbers. The results showed that the numbers of fungi in seawater in the cage culture areas averaged 252CFU/mL, arranging from 186CFU/mL to 350CFU/mL, which was more than 89.50% of that in the control area of 133CFU/mL, arranging from103CFU/mL to 216CFU/mL. The numbers of fungi in sediments in the cage culture areas averaged 559CFU/mL, arranging from 439 CFU/mLto 700CFU/mL, being more than 37.00% of that in the control area of 408 CFU/mL, arranging from 368CFU/mL to 438CFU/mL.The results showed that the number of fungi in seawater in the cage culture area had positive correlations with TN (r=0.612, p<0.05) and TP (r=0.791, p<0.01), the number of fungi in seawater in the control area had positive correlations with TN (r=0.638, p<0.05) and TP (r=0.801, p<0.01), the number of fungi in sediments in the cage culture area had positive correlations with TN (r=0.628, p<0.05) and TOC(r=0.733, p<0.01), and the number of fungi in sediments in the control area had positive correlations with TN (r=0.656, p<0.01) and TOC (r=0.680, p<0.05)The strains separated have been identified by 18S rDNA sequence analysis and shapeanalysis. The results showed that 7 categories of fungi, Candida sp., Pichia hansen., Aspergillus micheli., Penicillium sp., Cladosporium sp. and Rhodotorula sp., were identified. Candida parapsilosis and Candida colliculosa were dominant species.Utilization of nitrogen and carbon source by two dominant species (DY07-1 and DY11-1) have been examed by using nutrient medium and Biolog YT microplate. The results showed that favorite nitrogen source of DY07-1 and DY11-1 was yeast powder. The favorite carbon sources of DY07-1 were XC (Xylose Cometabolism) and SSD(Sugar and Sugar Derivatives); The favorite carbon source of DY11-1 is polymers and SSD.