| Actinomycetes is a kind of microbe that closely related with human life. It has great utilization value in industry, and has made great contribution for human. Only 10% ~20% actinomycetes could be isolated at present. Nearly 80% actinomycetes couldn't be isolated by traditional isolation methods. The exploration and utilization of unknown antinomycetes resource is an urgent problem of soil microbiology. The effect of microwave-pretreatment, soil particle size and soil suspension dispersant on the isolation of antinomycetes is reported in this research. The results are as follow:1. Adaptive microwave irradiation could significantly increase the total quantities of isolated actinomycetes, streptomyces and micromonospora in the high organic matter soil samples. While the microwave irradiation lasted within 3-15minutes, the total actinomycete quantities on GA and HA culture medium increased by 8.3%-92.6% and 24.4%-108.5% in comparison with those on the control medium, respectively. Adaptive microwave irradiation could significantly increase the newly identified actinomycetes species, which included such rare actinomycete genera as promicromonospora and streptoverticillium. While the microwave irradiations lasted within 3-24 minutes, the newly identified actinomycetes species, made up 62.5%-85.7% and 66.7%-83.3% of all the actinomycetes species on the GA and HA culture medium, respectively. Microwave irradiation could exert remarkable influence on the numbers of antimicrobial actinomycetes strains , while the microwave irradiations lasted 6,9 and 15minutes, the percentages of antimicrobial antinomycetes strains on the two culture mediums increased by 66.7%, 66.7% and 83.3% in comparison with those on the control medium, respectively.2. With the microwave irradiation durations increased, the dry soil presented total actinomycetes and streptomyces quantity that tended to initially increase and then decrease, the quantity of micromonospora increased significantly in comparison with the control medium. While the microwave irradiation lasted within 3 minutes, the total actinomycetes, streptomyce and micromonospora quantities increased by 71.3%, 102.9% and 212.5% in comparison with those on the control medium. Microwave irradiation exerted remarkable influences on the number of rare actinomycetes genera, and the percent of antimicrobial actinomycetes increased significantly in comparison with the control medium. While the microwave irradiation lasted within 9 minutes, the percent of antimicrobial actinomycetes up to 81.8%. The main genera of antimicrobial actinomycetes is streptomyces. 3. With the microwave irradiation durations increased, the microbe in fresh soil changed significantly, the quantities of bacteria get down and the quantities of fungi tend to initially increase and then decrease. With the microwave irradiation durations increased, the penicillium disappeared earlier than the aspergillus. Microwave irradiation showed no remarkable effects on the quantities of total actinomycetes, streptmycete and micromonospora in the fresh soil samples. While the microwave irradiations lasted within 3 and 15 minutes, the total actinomycete quantities on GA and HA culture medium increased by 65.0% and 3.5%, in comparison with those on the control medium, respectively, Microwave irradiation could significantly increased the quantities of micromonospora. While the microwave irradiations lasted within 3 and 9 minutes, the quantities of micromonospora on GA and HA culture medium increased by 92.9% and 280.0%, in comparison with those on the control medium, respectively.4. The species and quantities were various in different size fraction of soil. The smaller the soil diameter was, the more the quantities of antinomycetes, while the quantities of rare antinomycetes such as micromonospora increased obviously. The organic matter of soil had little effect on the quantities of antinomycetes and soil diameter. The media types had some influence on the species and quantities of antinomycetes and soil diameter. In media GA, a trend that the quantities of antinomycetes increase with the decrease of soil diameter was observed, while the total antinomycetes of 1# high organic matter grassland had increased 45.1% compared with control. In media HA, the quantities of antinomycetes, strepmyces and micromonospora were various in different soil samples, while the total antinomycetes of 1# high organic matter grassland had increased 44.0% compared with control. In media soybean flour, the quantities of antinomycetes were various when the soil diameter of different soil samples decreased, but the quantities of micromonospora accounted for the highest ratio of antinomycetes.5. The suitable concentration of CMC could significantly increased the quantities of actinomycetes. When the concentration of CMC is 2.5 g/L, quantities of actinomycetes and rare actinomycetes increased significantly. When the concentration of CMC is 3.0 g/L, quantities of actinomycetes in small soil diameter is 1.81 times of that in big soil diameter.
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