Screening, Identification And Primary Usage Evaluation Of Phosphate Solubilizing Microorganism From The Tropical Soil

Phosphorus is an important material foundation to a plant's growth. The total amount and yield of crops directly correlated with the amount of phosphorus absorbed by the crops.Most of soil are lack of phosphorus for crops because the phosphorus in soil is often in the status not easily absorbed by plants directly, although there are a lot of tontal phosphorus in soil. Accordingly, crops often grow poor if not any phosphorus supplied. The phosphate solubilizing bacteria is a kinds of bacteria making the combined phosphorus solubilizing and absorbable for plants. The usage of the phosphate solubilizing bacteria to supplement the soil absorbable phosphorus for plants is an attracting researh field all over the world. This research established a system of screening for phosphate solubilizing bacteria from soils and screened aobtained this kinds of bacterial isolates. The identification and primary usage evaluation of these isolates were done. The following if the detail report.1,When took organic phosphate bacteria culture medium and inorganic phosphate bacteria culture medium as basic culture medium, using liquid culture medium to processing organisms enrichment, and carrying on separative filtration by using tabulate dilution method, we finally got 107 bacterial strain. As the result shows, we can separative filtrate phosphate solubilizing bacteria effectively out of soil by using organic phosphate bacteria liquid culture medium as organisms enrichment culture medium and inorganic phosphate bacteria solid culture medium as filtration culture medium, then, we established a fast and effective phosphate solubilizing bacteria filtration system primarily. After the mensuration to phosphate solubilizing ability in envionments of Liquid and solid culture medium, as a result, it proved that the filtrated phosphate solubilizing bacteria have strong solubilizing ability, which further validated the feasibility of this filtration system.2,Through primary filtrating to collected soil with phosphate solubilizing bacteria filtration system, judging its phosphate solubilizing ability by phosphate solubilization technique, mensurating the phosphorus amounts to the filtrated solubilizing bacteria via Molybdenum blue colorimetric method, and carrying a ration mensuration and re-filtration to primary filtrated bacteria accurately, then, we finally found 37 bacteria with better phosphate solubilizing effect after the primary filtration and re-filtration.3,According to bacteria colony's fostering feature, physiology & biology chemistry identification and 16SrDNA sequencing's analysis and comparing, we identified 37 bacteria like that PSB3 is Burkholderia cepacia, PSB4 is Burkholderia Sp, PSB13 is Burkholderia sp., PSB15 is Salmonella enterica subsp., PSB26 is Klebsiella sp., PSB58 is Uncultured Pseudomonas sp., PSB67 is Burkholderia anthina and PSB77 is Burkholderia sp. etc.4,Take pre-filtrated phosphate solubilizing bacteria as stand-by test bacteria, and take 15 Fusarium oxysporum piperis pathogens supplied by Environment and Botany Protection Institute of China Tropical Agriculture Academy as testing bacteria, then, applying 5 points bacteria-linking method to connect testing bacteria at the center of PDA board, and connect phosphate solubilizing bacteria around them for an antagonism experiment. The results showed that PSB15 filtrated phosphate solubilizing bacteria had antagonism reaction against some of the pathogens testing bacteria. When taking a configuration observation to some pathogens testing bacteria which are out from antagonism reaction, we found they have some obvious changes.5,When applying the best 8 phosphate solubilizing bacteria from filtration, PSB3,PSB4,PSB13,PSB15,,PSB58,PSB67,PSB77 and etc, into seeds germinating experiments of tomato, soybean, wheat and sunflower these 4 crops which are hypersensitive to phosphorus. As a result, bacteria PSB3,PSB4,PSB13,PSB15,PSB58,PSB67 and PSB77 have obvious catalyzing effects to those experimental seeds.6,When taking 5 phosphate solubilizing bacteria, PSB4,PSB13,PSB26,PSB58,and PSB67, into soybean warm canopy breeding experiment, the result shows all those five bacteria have obvious catalyzing effects to soybean's seedling growth and yield. Moreover, the yield are always 2 times to sterile water as negative. When using PSB26 bacteria for potted sunflower experiment, as a result, PSB26 is also having a visible facilitate function to sunflower's seedling growth.