Effect Of Organic Management On Soil Microbial Population Characteristics And Enzyme Activity Of Melon Field

Changes of soil microbial,soil nematodes and activities of enzymes on organic management melon,the dominant fungi and bacter ia in Minqin County of Gansu Province were studied in this paper.The key results are as follows:1.Effect of organic management on the number of soil fungi, bacteria, actinomycetes of the Melon fieldThe number of organic soil fungi,bacteria,actinomycetes were significantly more than conventional field.And the number of actinomycetes were decreased with the growth of melon.The identification of fungi showed that in organic and conventional field, Fusarium.sp,Phytophthora and Rhizoctonia were main group in different growth of melon soil.The number of Fusarium were accounted for more than 35.1%, and the peak value was 40.35%.In organic and conventional field,characteristics change of soil microbial is flowering period for the demarcation line, and the number of soil microbial increased in earlier stage and decreased later period. In the same growth period,the number of Fusarium.sp,Phytophthora and Rhizoctonia in organic management field is significantly more than conventional fiels.The results of bacteria separate showed: in organic and conventional field, Mq1,Mq2 were main microbial group in different growth on melon soil. and in the two field contained a certain number of Mq3. the number of Mq1,Mq2,Mq3 in Organic management were more than conventional field.2.Effect of organic management on the number of physiological flora of soil microorganisms of Melon field.In different management and different growth period ,the changes of each kind of microorganism were clearly. The number of physiological flora of soil microorganism were significantly in organic management more than conventional field.but not the same trend.With melon growth ,the number of nutrifying bacteria reduced and oligotrophic azotobacter,aerobe azotobacrer increased.the number of aerobe celluloytie,oligotrophic cellulolytie were the most in flowering period. 3.Effect of Organic management on activities of enzyme of Melon field Change of activities of enzymes:The changes of activities of soil enzymes were related with melon grow season: the activities of catalase,invertase and urease were all increased in different grow seasons from organic management to conventional field.The activities of catalase was smooth changes in full fruit period, the activities of invertase were the most in flowering period.but activities of urease were the most in maturity.4.Effect of organic management on the number of soil nematodes of Melon fieldThe soil nematodes density was obviously increases after executing into the organic fertilizer,the number of soil nematodes in organic managemen was higher in conventional fields.the number of soil nematodes was the most in flowering period. great variety of melon nematodes,the nematodes which separated from the melon root system and the rhizosphere was appraise 10 genus and 2 kings.there are Aphelenchoides.sp,Pratylenchus.sp,Meloidogyne.sp,Paratylenchus.sp,Paratrichodorus.sp,Ditylenchus.sp,Helicotylenchus sp,Seinura.sp,Aphelenchoides sp,Tylenchulus.sp,Xiphinema sp,Meloidogyne hapla chitwood,Meloidogyne exigua.