3种饵料金藻的超低温保存研究↑（*）

用两步冷冻法研究绿色巴夫藻（Ｐａｖｌｏｖａｖｉｒｉｄｉｓ）、湛江等鞭金藻（Ｉｓｏｃｈｒｙｓｉｓｚｈａｎｊｉａｎｇｅｎｓｉｓ）、球等鞭金藻（Ｉ．ｇａｌｂａｎａ３０１１）的超低温保存（液氮，－１９６℃），探讨了影响存活率的内、外因素。结果表明，降温速率０．７℃／ｍｉｎ，预冻温度－４０℃，预冻时间３０ｍｉｎ时可获得较高的存活率。１５％ＤＭＳＯ或１５％ＤＭＳＯ＋１０％蔗糖是良好的抗冻保护剂。某些藻类在生长静止期或在低于最适温度下培养时可显著提高其存活率。通过控制内、外条件，３种金藻的存活率都可达到３０％以上，比以往的报道有显著提高。

Cryopreservation of 3 golden algae (Chrysophyta) used as feed in mariculture

Pavlova viridis, Isochrysis zhanjiangensis and Isochrysis galbana were cryopreserved in liquid nitrogen with the method of two-step cooling.The survival rates were higher when the cooling rate was 0.7/min and the final temperature in the first freezing step was -40 and the holding time was 30 min.15% DMSO and 15%DMSO plus 10% sucrose were effective cryoprotectants.The survival rate of algae during stationary phase of growth or cultured below the optimum temperature was high sometimes.Under suitable conditions of cryopreservation,the survival rates of all the 3 algae could be raised up to over 30%.