淡水噬藻体及其他溶藻因子的分布与感染力

研究了不同时空条件下噬藻体的分布与效力的变化.2001年8～11月共采集了18个水样,对14种藻进行直接感染,从其中的5个水样中分离到了噬藻体(蓝藻病毒),它们主要来源于降温以前富营养化池塘的水样,同时分离得到了4株溶藻细菌.在接受直接感染的14种藻中,聚球藻、组囊藻、微囊藻、织线藻、鱼腥藻7120、衣藻及小球藻为敏感种类,而螺旋藻、念珠藻、鞘丝藻、颤藻、鱼腥藻595、鱼腥藻1444、栅藻则为不敏感种类,敏感种类中织线藻受到噬藻体的感染,聚球藻、微囊藻和织线藻受到溶藻细菌的溶解.从富营养化的池塘采集的水样溶藻能力最强,其次为清水(自来水源)池塘,而大中型湖泊与河流水样的溶藻效果最差.随着温度的降低,水样的感染能力下降.

The distribution and infectivity of cyanophage and other algae-lysin factors in fresh water

The changes of distribution and infectivity of cyanophages in different time and space conditions were studied. 18 water samples were collected from August to November, 2001 and 14 species of algae were directly infected. At last, in 5 samples, cyanophage (blue green alga virus) was separated, the source of which was mainly the water sample of eutrophic ponds before temperature descendension; meanwhile, 4 strains of algae-lysin bacteria were separated. Of the 14 strains of directly infected algae, Synechococcus, Anacystis, Microcystis, Plectonema, Anabaena 7120, Chlamydomouas and Chlorella were sensitive, while Spirulina, Nostoc, Lynbya, Oscillatoria, Anabaena 595, Anabaena 1444 and Scenedesmus were unsensitive. Plectonema was infected by cyanophage; synechococus, Microcystis and Plectonema were dissolved by algae-lysin bacteria. It was also found that the water samples collected from eutrophic ponds showed most strong algae-lysin ability; and the next was the samples collected from clean water (tap water) while those from big or mid lakes and rivers were the weakest. The infectivity of water samples decreased with decrease of temperature.