| Crop straw, the agricultural production waste, which is rich in nitrogen, phosphorus,potassium, trace elements and organic carbon, is an important organic fertilizer. Rice straw resources are renewable and widely distributed in China, free burning not only pollutes the environment, but also wastes the resources. In this paper, through the fermentation of rice-straw decomposing strains, we obtain the rice-straw decomposing microbes agents.This research is about the shelf-life time of the rice-straw decomposing microbes agents,which are applied in the straw- composting, rice-seedlings and practice field production.Now the results are summarized as follows:(1) In the first 180 days for agents detected,the effective number of viable bacterium was 6.62×108 cfu/g, and the fungus was 1.83×108 cfu/g; p H remained stable along with preservation time, ranging between 6.0-7.0; The moisture content decreased less than 20%at the time of 120-day and than stabilized; What’s more, cellulase activity generally tended to reduce in the first 120 days, afterwards it stabilized and measured up 50.16ug/g at180-day. The study showed that the compound decomposing agents basically reached the national standard requirements of agricultural microbial agents, and the shelf-life was longer than six months.(2) In the aerobic compost test with rice-straw, twelve indicators were tracked by straw color, temperature, moisture content, p H, electrical conductivity, density and porosity, germination index, organic matter, total N, C / N ratio, and microorganisms population. Compared with CK, the results showed that adding decomposing microbes agents can effectively promote microbial fermentation, heighten the pile temperature and the top temperature and extend the high temperature phase, thus shortening composting time. Moreover, Microbial inoculants were in favor of accumulation of nutrients and terminated the phytotoxicity ahead of time, as well as reduced the loss of nitrogen and improved seed germination index.(3) By employing investigation on seedling quality, and measuring root activity,chlorophyll, soluble sugar content, root twisting power and root growth ability in different growth stages, to study the effect of the compound decomposing microbes agents on the rice seedlings. We found that the compound decomposing microbes agents with a suitable concentration(5%) have played a significant role in promoting the growth of rice seedlings. They help accelerate the growth rate of rice seedlings, while improve their various physiological qualities. Compared with CK, the seedling height, pseudo-stem width, leaf width, leaf length, sheath length, the total number of roots and white roots,main root length, fresh weight, dry weight, have respectively improved 14.41%, 50.17%,5.77%, 0.87%, 0.95%, 11.02%, 36.81%,8.45%,47.39%,and 43.80%, the differences were significant. The agents not only extremely significant improved root activity, chlorophyll,soluble sugar content,but also root twisting power and root growth ability, they wereseparately increased by 58.30%, 43.04%, 8.33%, 57.70% and 93.92%.Furthermore,total phosphorus content of the three treatments plants was almost no difference, while total potassium and nitrogen content of plants with agents inoculation of 5% were increased by55.99% and 16.67%,They were significantly higher than that of CK.(4) Through enzyme activities and mineral elements change measuring experiment in rhizosphere soil. We found that, the compound decomposing microbes agents can significantly improve the rice rhizosphere soil enzyme activities, among which the urease,sucrase, cellulase and catalase activity were 24.49±0.88mg/(g·24h),0.60±0.05mg/(g·24h),0.31±0.0083mg/(g·72h),0.43±0.01ml/(h·g).Compared with CK,they have increased by 43.72%,7.14%,47.62%,10.26%;Urease is involved in Nitrogen cycle, sucrase is sensitive to changes in organic matter, cellulase is involved in the decomposition of organic matter, catalase promote the decomposition of hydrogen peroxide to prevent toxic effects. There was almost no difference in nitrogen content when compared to CK, while the organic matter, total nitrogen, available phosphorus and potassium content were significantly higher, they were increased by 67.67%, 35.57%,48.98%, 42.43%;The compound decomposing microbes agents can at some extent improve soil fertility, so as to provide a favorable environment for soil nutrients and crop growth.(5) We explored the change in the composition of rhizosphere microbial community structure through MPN determination of microbial function and T-RFLP analysis. The results showed that the compound decomposing microbes agents can inhibit the growth of pathogenic microorganisms in soil, improve soil microbial ecology structure,and prompt the growth of beneficial microorganisms and other functions, forming the dominant flora, so that some can be involved in improving soil properties, degrading soil allelochemicals and promoting nutrients cycle. Through synergistic effect between soil microorganisms, soil microbial communities tend to be a dynamic equilibrium, and accelerate the conversion of nutrients, thus contributing to the growth of rice seedlings.(6) In the machine-transplanted cultivation mode, compared with a single full amount of straw back to filed, soil bacteria, actinomycetes and fungi have significantly increased in the treatment with the compound decomposing microbes agents. Dry matter and actual yield were increased by 7.46% and 5.92%, which effective ear differed significantly.Nitrogen, phosphorus and potassium were increased by 8.46%, 8.14% and 7.07% in the rice maturity, respectively.In summary, the compound decomposing microbes agents has excellent shelf-life, not only can shorten the time of straw decomposition, but also has a significant growth-promoting effect, Which possesses good prospects in the production of agricultural practices. |
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