Effect Of Bioorganic Fertilizer Containing Sorbitol On Plant Growth

The over use of chemical fertilizers has caused a series of problems such as soil compaction and acidification and decreasing organic matter and soil microbial activity.In order to solve these problems,partial replacement of chemical fertilizer by organic fertilizer has become the state policy.Bio-organic fertilizer can provide nutrient to the crops and beneficial microorganisms to the soil as to promote plant growth and suppress soil borne disease.However,if the beneficial microorganisms can colonize in the soil is the key for the bio-orgnaic fertilizer to function.In this study,sorbitol and Bacillus amyloliquefaciens SQR9 were added into the organic fertilizer and the effect of the novel bio-organic fertilizer on tomato and cucumber growth was evaluated by pot experiment.The pot experiment was conducted with four treatments including OF+S(organic fertilizer+sorbitol),OF+SQR9+S(organic fertilizer+Bacillus amyloliquefaciens SQR9+sorbitol),OF(organic fertilizer),and OF+SQR9(organic fertilizer+Bacillus amyloliquefaciens SQR9).The results of the pot experiment showed that the addition of sorbitol or SQR9 can inprove both the cucumber and tomato growth.The growth promotion effect of OF+SQR9+S treatment was the best than other treatments that it had the highest plant height,stem diameter,total root length and root surface area,and fresh and dry above groud biomass.The addition of sorbitol or strain SQR9 also significantly changed the chemical characteristics of both the cucumber and tomato soils.The addition of sorbitol and strain SQR9 increased the soil fertility by increasing the soil available phosphorus and potassiumas as well as ammonium and nitrate.The OF+SQR9+S treatment also had the highest nitrogen,potassium and phosphate absorption rate compared to other three treatments which are significantly correlated to plant hight and stem diameter.The addition of sorbitol significantly increased the number of bacteria and actinomycetes but decreased the fungal abundance in the tomato soil.While the addition of sorbitol significantly increased the number of bacteria,but decreased the number of actinomycetes in the cucumber soil.The addition of sorbitol increased the colonization of strain SQR9 in both the tomato and cucumber soils.The adition of sorbitol alone significantly increased the bacteria fungi rate,while no significant difference was detected between each two of other three treatments.In summary,the application of bio-organic fertilizer containing sorbitol and Bacillus amyloliquefaciens SQR9 significantly promoted the growth of tomato and cucumber by increasing the content of available nutrients,the colonization of strain SQR9,and the bacteria abundance in the soil resulting in higher nutrients absortion rate.