Tham khảo tài liệu 'fungicides for plant and animal diseases part 3', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Applications of Actinobacterial Fungicides in Agriculture and Medicine 31 32 Fungicides for Plant and Animal Diseases Plate 1. Cultural and microscopic view of Streptomyces isolates aerial mycelium with spores Applications of Actinobacterial Fungicides in Agriculture and Medicine 33 Fig. 1. Antifungal activity of Extra and Intracelluar compounds of Streptomyces isolates 2. In vitro screening methods of fungicidal substances produced by actinobacteria Crowded plate technique A series of test tubes containing 9 ml of sterile water was taken. From the stock culture 1 ml suspension was transferred aseptically to the 1st tube 10-1 and mixed well. Further serial dilutions were made to produce 10-5 suspensions. Suspension ml from each test tube was spread on sterile soyabean-casein digest medium SBCD actinobacteria isolation agar AIA medium and starch-casein agar medium plates aseptically in a laminar air flow cabinet. The plates were incubated at 27 2 C for 84 h. The plates were observed intermittently during incubation. After 72 h whitish pin-point colonies characteristic of actinobacteria and with clear zone of inhibition around them were observed. The pinpoint colonies with inhibitory or clear zone of inhibition were selected and purified and used as a potent isolate for fungicidal compound production. Agar streak method The Fungicidal activity of the soil actinobacterial isolates were analyzed by agar streak method. Each of the isolate was streaked as a straight line on Starch casein agar SCA medium and incubated at 27 C for 6 days. After the 6th day different fungal pathogens were streaked at right angle but not touching each other and then incubated at 28 C for 48 h. If the organism is susceptible to the antibiotic produced by actinobacteria then it will not grow near the actinobacteria. The zone of inhibition against each test fungal pathogen was noted. Agar disk method The Streptomyces isolate was smeared on SCA medium as a single streak and .
