Isolation And Identification Of An Algicidal Fungi And Its Algicidal Characteristics

The environmental pollution caused by eutrophication is serious. We have gradually adopt physical, chemical and other methods of treatment, they are more or less have their own shortcomings, environmentally friendly biological methods of algae-bloom management has become the focus in the field.About 40 strains of fungus were isolated from the soil of humus-rich region containing the bank of East Lake and YanDong Lake of WuHan, our university, ZhengZhou University, and some leaves under the vicinity of Pine from Miao Lake of WuHan. After repeat screening, the strain named J20 has the algae-lysing effect. By morphological observation, there were many slender and straight conidiophore, lots of green spherical conidiospora, they were all with smooth wall. Combined with 18SrDNA sequence, J20 was identified as Peniciliium.J20 lysed Microcystis aeruginosa DS by exreting extracellular substance, and the major algae-lytic substance was non-protein and thermo-stable.By studying the shaking-time conditions, the results were as follow:ChaShi culture medium, sucrose sources,150mL liquid culture medium in 250mL flasks,28℃,160r/min through 4 days' shaking cultivation. On the third day in experiment, the etiolation was appeared,compared with control group the content of Chla declined,82%of Microcystis aeruginosa DS had been removed in 3 days.After adding EDTA and Tween-80 at 24h during shaking-culture time, the lytic efficiency of the former experimental group has improved by 10%compared with the experimental group of J20, but the latter group almost has no algae-lysing effect.Algicidal pattern and cultural conditions were studied in this paper, we hope that it could provide the basis of algicide exploitation.