The Researches Of Potassium Shale Fertilizer Including Strain Breeding And High Density Fermentation Process

In recent years, with the adjustment of planting structure, and constant improvement of crop yields and cropping index, the consumption of nitrogen, phosphorus and potassium elements in soil increase, and the deficiency areas of them even gradually expand. In order to maintain soil fertility, people has been used to apply fertilizer on their fields, which would improve soil fertility and crop yields quickly and effectively. However, over the long term, it always causes soil compaction and damages to soil structure, resulting in production decline. For this reason, farmyard manure and new bacterial manure will be favored by people. Bacterial manure is a new kind of green fertilizer, which is safe and environmentally friendly with the function of two-way regulating the soil fertility.According to the geological survey, Taihang Mountains and Lvliang Mountains contain hundred millions tons of potassium shale. Potassium shale belongs to rich-potassium sedimentary rocks and composes paramount minerals of potassic fertilizer. In addition, potassium shale was analysed and contains other trace elements which is essential to plant growth, such as phosphor, sulfur, iron, zinc, copper, manganese, molybdenum, boron, selenium, sodium. But, these sylvites and phosphorous exist in mineralized form that can’t be absorbed by crop directly, so that it is needful to transform by related microorganisms and turn into cyclical biological process in the end.The purpose of this research is to explain the indigenous strains isolated from potassium shale potassium shale mine and to carry out mutation breeding in order to improve the production traits of it. After that, we will study on fermentation conditions and the establishment of fermentation production technology to research and development of a microbial fertilizer.In this paper, we used potassium shale dissolved circle as the index, and application of plate separation method for screening and potassium stress test method for compound screening. At last we obtained a strong ability of potassium bacteria and after the classification and identification, we named it Bacillus mucilaginosus HSC. The cell concentration of strain in fermentation liquid can reach 1.6×109cfu/mL and Bacillus spore yield can reached 1.2×109cfu/mL. Its spore conversion rate is 75% and the ability to decompose potassium shale is 2.6μg/mL.Through the releasing from the UV and Nl4+ ion beam implantation breeding, we get the strain HSCUP-76-8 which ability to decompose potassium shale is 2.8μg/mL and high concentrations of bacteria in the fermented liquid is 2.3×109cfu/mL, Bacillus spore yield can reached 1.9×109cfu/mL spore conversion rate is 82.6%.We studied the fermentation conditions of Bacillus mucilaginosus HSCUP-76-8, by the single factor test and orthogonal test to optimize the formula of culture medium and culture condition, that is, the culture temperature is 32℃, pH is 7.5, and ventilation is 1:1. According to the cell growth curves and rules of Bacillus mucilaginosus HSCUP-76-8, we set up two stage control model, that is cell growth stage and Bacillus transformation stage, though the fermentation conditions of espectively and differential control, The cell concentration of strain in fermentation liquid can reach 2.8×109cfu/mL and Bacillus spore yield can reached 2.3×109cfu/mL. Its spore conversion rate is 82%.The cycle of fermentation method of high density fermentation of two stage is 32～48 hours.Through isolated and screened we obtain potassium bacteria from the potassium shale mining area and obtained a excellent production traits mutant strain producing through mutagenesis and set up two stages of high density fermentation, which laid the foundation for the production and application of potassium shale fertilizer.