耐高温球等鞭金藻(Isochrysis galbana)藻种的选育与饵料特性初步分析

BREEDING AND FEEDING CHARACTERISTICS OF HIGH-TEMPERATURE-RESISTANT STRAINS OF ISOCHRYSIS GALBANA

通过显微操作技术从海水饵料微藻培育池中分离出4株球等鞭金藻(Isochrysis galbana)藻株,测试其在高水温(33℃,40℃)下的生长性能;对藻株的颗粒大小和粗蛋白含量进行了测定;筛选出一株生长速度较快的球等鞭金藻PHY7004,优化了其培养条件;分析了单环刺螠幼苗对其的摄食能力。结果表明,分离出的4株球等鞭金藻可在水温33℃下生长,其中PHY7004生长速率最快;分离出的各藻株细胞的平均直径为5.5-7.5μm;耐受33℃的4株藻株平均鲜重蛋白质含量为34.29 mg/L,其中PHY7003蛋白质含量最高,为41.80 mg/L;优化后的最适培养条件为pH=7,N/P=14:1;单环刺螠幼苗对PHY7002的摄食强度较高。本实验为耐高温饵料藻种的筛选提供参考,也可为单环刺螠育苗所用的饵料微藻的选择提供依据。

Four strains of Isochrysis galbana,named PHY7001—PHY7004,were isolated in microscope and tested for their growth characteristics in high temperatures(33℃,40℃).The cell size and protein content of the strains were determined and the medium of the one with the fastest growth rate(PHY7004)was optimized.In addition,we conducted feeding experiment of Urechis unicinctus seedlings.Results show that the four strains could grow best at 33℃,of which the growth rate of PHY7004 was the biggest.The average diameter of cell size was 5.5—7.5μm,the average fresh-weight protein content of the 4 strains was 34.29 mg/L,of which the protein content of PHY7003 was the highest:41.80 mg/L.The optimum culture conditions for the fast-growing PHY7004 were pH=7 and N/P=14:1;and U.unicinctus seedling of PHY7002 feeding intensity was the highest.This study provides a reference for screening of high-temperature-resistant bait,and a basis for the bait selection of U.unicinctus seedling.