Study On Bacteria Communities Of Straw-decomposing Inoculant And The Dynamic Change In The Pcocess Of Fermentation

In this study, the bacteria composition and the dynamic changes of the straw-decomposing inoculants were analyzed by culture dependent method and molecular biology method. The 16S rDNA clone library method is more impersonal and exactly for analyzing the samples' bacteria composition than the culture dependent method. Now, PCR-DGGE is one of the best methods to study the dynamic changes of inoculants in the process of fermentation. The result of this study would offer help for the rational composition,production and application of straw-decomposing inoculants.The main results of this study were as follows.Using 16S rDNA clone library method, the bacteria composition of the sample A and B were investigated. The results indicated that: the dominant communities of sample A were Weissella confuse, Bacillus subtilis and Bacillus pumilus, and the dominant communities of sample B were Lactobacillus buchneri, Lactobacillus farciminis and Lactobacillus acetotolerans. This study showed that 16S rDNA clone library method had nicer application perspectives in analying the bacteria of microbial inoculants and its quality control than the culture dependent method.Using DGGE, two forms of fermentions were analyzed, one was aerobic,the one was anaerobic.Their image patterns had much difference from each other, but the two samples' image patterns of the same form of fermention were similar. And the interesting bends' sequencing results were different from sample's bacteria composition.The small compost joined sample A and B was analyzed with DGGE and culture dependent method, mainly studying the dynamic changes of microbe. At the same time ,we also mensurated the interrelated parameter, such as temperature,pH,water content,C/N and seed germination rate. The results showed that, the use of straw-decomposing inoculants could make the compost go on wheels; the microbe in compost had obviously succession. First, the lactobacillus and bacteria of normal tempeture increased strongly, then the temperature was heightened, at this time, high temperature actinomycetes and bacteria began to increase strongly, at the end of the fermentation, they would become less and less, however, normal tempeture bacteria increased again. The result of DGGE showed that, the primary bacteria of compost was different in the total process of fermentation. And the sequencing results told us: the primary bacteria in the compost were uncultured bacteria, they weren't the same primary bacteria in samples.This study showed that, 16S rDNA clone library method and DGGE can be used good in analyzing bacteria composition of microbial inoculants and quality control.That was very important for improving the quality of inoculants and microbial fertilizer.The method of Bead-beader was suitable for large content DNA extraction, perpendicular gradient gel must be done before that DGGE was used in analyzing complex samples.