The Microbial Flora On The Surface Of Laminaria Japonica And In Its Cultivation Seawater And Isozyme Analysis Of The Kelp During Its Decaying Process

This paper analysed the variation of bacterial biomass on the surface of Laminaria japonica and in its cultivation seawater system, during the period of L. japonica decaying. The microbial flora on the surface of the kelp and in its cultivation seawater was investigated. At the same time the relationship between bacterial biomass and rot disease occurrence were studied. The zymogram features of some isozyme of the Kelp in Different Physiological Stage were also investigated. The results were shown:1.Total bacterial number, viable bacterial number and heterotrophic bacterial number tended to increase throughout the process, among which heterotrophic bacterial population were the active groups and their number showed distinctive increase. Correlation of viable bacterial number as well as heterotrophic bacterial number on the surface of Laminaria japonica and in its cultivation seawater system was significant.2.The main compounds of microbial flora on health alga surface were Photobacterium, Pseudomonas, Aeromonas and Vibrio. The diversity of bacterial communities on the surface of the kelp increased at first and then declined with the alga becoming decayed. The major bacteria causing Laminaria rot disease were identified to be Alteromonas.3.The enzyme banding patterns of healthy L. japonica and those of decayed L. japonica were different. Three new isozyme bands of POD appeared after nine days cultivation of the kelp and some isozyme bands disappeared with the kelp becoming decayed. No new isozyme bands of PPO and MDH appeared during this period and some isozyme bands disappeared.