Screening,Identification And Enhancement To The Growth Of Phosphate Solubilizing Bacteria In Rhizosphere Of Camellia Oleifera Abel

Camellia oleifera Abel is a uniquely economic forest in China,it has important economic value and ecological benefits,also plays an important role in forestry development and ecological construction.Especially to raise the level of red soil region agricultural economy has a positive role.Red soil of phosphorus has a strong adsorption force.The lack of soil phosphorus and accumulated relatively serious problem,it is difficult to meet the required for plant growth.Therefore,fertilizing phosphorus fertilization is increasing Camellia oleifera production necessary basic technical measures.However,with the development of modern agricultural economic demand,fertiliser use increase gradually,many bad negative effect also will increase.The researchers started to look for the new fertilizer in this field.And they begin to pay close attention to biological fertilizer instead of traditional chemical fertilizers in recent years.The study of sollubilized phosphorus strains are mostly concentrated in the often crops such as maize,rice,wheat,etc.And the perennial economic forest?camellia,walnuts,pine,etc.?rhizosphere soil soluble phosphorus strains less detailed research report system.Few studies on red soil region were the main production area?Jiangxi province and Hunan province?rhizosphere sollubilized inorganic phosphorus bacteria.In this study,rhizosphere soil of 10-years-old Camellia oleifera plants were sampled separately in Jiangxi province and Hunan province.PSBs with high efficient ability of organic phosphorus were screened out from the rhizosphere soil samples.PSBs were identified effectively according to their morphological characteristics,physiological and biochemical properties and 16 SrDNA sequencing.The culture conditions were optimized through orthogonal experiments for PSBs,and explored the safety of efficient PSBs.At the same time,PSBs with high ability of solubilized phosphorus were inoculate into one-year-old seedings of Camellia oleifera to observe the inocution effects on seedling growth,nutrient uptake and soil nutrient content,the influence of the soil microorganism quantity and soil enzyme activity.The mian results acceding to this study are as follows:1.Organic phosphate-solubilizing bacterias were isolated from Camellia oleifera rhizospheres using selective culture madia and the molybdenum anti spectrophotometric method.The phosphate-solubilizing capacities were investigated from 20 strains based on qualitative and quantitative test.The results show that:?1?there was no such correlation between D/d and the phosphate solubilizing capacity,there was a significant negative correlation between the pH medium?X?and the phosphate solubilizing capacity?Y?,?R²=0.5011**,P<0.01?,the linear regression equation is Y=-131.71X+1090.3,there was a significant negative correlation between OD₆₀₀?X?and the phosphate solubilizing capacity?Y?,?R²=0.4249**,P<0.01?,the linear regression equation is Y=-584.85X-79.05.?2?PSBs have capable of efficiently sollubilized phosphorus sollubilized phosphorus bacteria each processing effective phosphorus content in the fermented liquid were significantly higher than that of controls?54.33 mg/L?,the significant difference between the groups.20 strains of effective phosphorus content of soluble phosphorus bacteria to deal with fermented liquid at 385.92 mg/L-494.78 mg/L,and between the growth rate of 331.59mg/L-440.45 mg/L,soluble phosphorus rate is between 8.84%-11.75%.And the strain JX285 fermented liquid effective phosphorus content in the highest?494.78mg/L?,is 9.10 times that of the CK,soluble phosphorus rate was 11.75%.HN038times,the effective phosphorus content of the fermented liquid is 475.01 mg/L,is8.74 times that of the CK,soluble phosphorus rate was 11.22%.?3?Bacteria were identified by morphological,physiological and biochemical characteristics,Biolog system and 16S rDNA gene sequence analysis.The high effective PSB of HN038,JX285,JX039?HN075?,HN053?JX068?were identified as Pseudomonas.Auricular,Bacillus aryabhattai,Pectobacterium cypripedii,Enterobacter ludwigii.2.This stuy used with orthogonal experiment design was optimized efficiently JX285and HN038 optimal sollubilized phosphorus condition.Results show that:?1?Every factor has a significant influence on phosphate-solubilizing ability of JX285,best soluble phosphorus condition is A₂B₂C₁D₃,and the greatest influence factor on phosphate-solubilizing ability was the temperature.The optimum carbon source and nitrogen source were glucose and?NH₄?₂SO_4.The JX285 displayed a better phosphate-solubilizing capability when the temperature was 28?,medium initial pH was 7.5,inoculation quantity was 1%and aeration quantity was 100 mL.Its influence factors in the order:temperature>pH>oxygen>quantity.After optimizing the culture medium of soluble phosphorus content was 586.73 mg/L,than in ordinary sollubilized soluble phosphorus medium phosphorus content?404.20 mg/L?by45.16%.?2?Every factor has a significant influence on phosphate-solubilizing ability of HN038,best soluble phosphorus condition is A₂B₁C₁D₁,and the greatest influence factor on phosphate-solubilizing ability was the temperature.The optimum carbon source and nitrogen source were glucose and?NH₄?₂SO_4.The JX285 displayed a better phosphate-solubilizing capability when the temperature was 28?,medium initial pH was 6.5,inoculation quantity was 1%and aeration quantity was 25 mL.Its influence factors in the order:temperature>pH>oxygen>quantity.After optimizing the culture medium of soluble phosphorus content was 520.96 mg/L,than in ordinary sollubilized soluble phosphorus medium phosphorus content?352.57 mg/L?by47.76%.3.Results show that the cblA gene was not detected on JX285 and HN038,and be safe on allium cepa and medicago sativa.There is important significance on the safe application of phosphate-solubilizing and improve the availability of phosphorous in Camellia oleifera soil.4.PSBs with high ability of solubilized phosphorus were inoculate into one-year-old seedings of Camellia oleifera to observe the inocution effects on seedling growth,nutrient uptake and soil nutrient content,the influence of the soil microorganism quantity and soil enzyme activity.The results showed that:?1?Three kinds of soluble phosphorus bacteria agent can promote the camellia plants in different degrees of plant height,biomass,net photosynthetic rate,leaf,nitrogen content and phosphorus content.?2?Camellia oleifera rhizosphere soil alkali-hydrolysable nitrogen,available phosphorus and available potassium content all have varying degrees of increase.?3?three kinds of bacteria agent can increase the Camellia oleifera the number of bacteria and actinomyces in rhizosphere soil,reduce the number of fungi,improve soil invertase and urease activity.?4?Sollubilized phosphorus bacteria agent under the condition of low phosphorus stress,better able to play a role of soluble phosphorus and grows.?5?In different sollubilized phosphorus bacteria agent and phosphorus levels,and from mixed bacterium agent is better than a single agent,test CK1 and CK2 indicators for all trials can not influence the results.