Study On The Improvement Effect Of Bio-organic Fertilizer On Continuous Cropping Soil Of Muskmelon

As a kind of microbial fertilizer,bio-organic fertilizer plays an important role in improving the structure of soil microbial community,increasing soil fertility,improving the nutrient supply and promoting plant growth.Facility cultivation is the main cultivation method of muskmelon at present,which plays an important role in early fruit market time,realization of annual supply and increasing farmers' income.Due to the limitation of cultivation conditions and the drive of economic interests,the phenomenon of continuous cropping of muskmelon in facilities is widespread,and the continuous cropping obstacles are very serious.In this paper,pot experiment was used to study the soil of muskmelon in Qingxian of Hebei Province.The effects of continuous cropping years of muskmelon on soil nutrient content,enzyme activity and the number of culturable microorganisms were studied.The correlation between soil micro-ecological environment and muskmelon growth was analyzed.Bio-organic fertilizer containing Bacillus megaterium and Bacillus amyloliquefaciens as an improver.To study the effect of different fertilization on the soil improvement of muskmelon continuous cropping,and the comprehensive scores of different treatments were evaluated based on principal component analysis.The results are as follows:1.Soil analysis of muskmelon planted for 1,5 and 10 years.Compared with the 1-year planting,the soil organic matter and available P content of continuous cropping for 5 years increased,and the alkaline N,available K,total N,and pH nutrients decreased.In the 10 years of continuous cropping,the soil nutrient indicators decreased,and the contents of alkaline N,available P,available K,and total N decreased by 24.49%,24.17%,31.17%,and 14.74%,respectively.2.Soil sucrase and alkaline phosphatase decreased with the extension of continuous cropping years.Compared with the soil in one year,the invertase and alkaline phosphatase decreased by 21.80%,18.29%,18.70% and 21.92% respectively in five and ten years of continuous cropping respectively.However,the catalase activity decreased first and then increased,and decreased significantly in continuous cropping for 5 years.3.The number of culturable microorganisms in soil also changed with the extension ofcontinuous cropping years.Compared with 1-year soil,the number of bacteria in 5 and 10 years of continuous cropping decreased by 52.54% and 57.25%,and the number of fungi increased by 143.18% and 106.82% respectively.It is indicated that prolonged cropping years make the soil appear fungal.There are also significant differences in muskmelon growth in different continuous cropping soils.Plant height,leaf area,true leaf number and chlorophyll of muskmelon decreased significantly in 10 years of continuous cropping,stem diameter and dry weight on the ground decreased significantly with the increase of continuous cropping years.Correlation analysis showed that continuous cropping soil fungalization,decreased alkaline P activity,total N,alkaline N,available P,and available K deficiency would affect the growth of muskmelon seedlings.4.Effects of applying bio-organic fertilizer on soil properties and seedling growth of muskmelon continuous cropping.In addition to pH,the contents of soil organic matter,alkaline N,available P,available K,and total N increased significantly with increasing fertilization under different growth days.Compared with CK,fertilization treatment increased the soil enzyme activity,the number of bacteria and actinomycetes and inhibited the number of fungi.At 30 days of growth,T1,T2 and T3 significantly reduced the number of fungi by28.43%,40.20% and 56.86%,respectively.Through the comprehensive score analysis of the principal components,the overall improvement of the T2 treatment is the best.When grown for 30 days,T2 treatment significantly increased the muskmelon plant height,stem thickness,above-ground dry weight,leaf area and true leaf number by 32.81%,5.24%,38.39%,58.00%,75.00% compared with CK.In summary,continuous cropping of muskmelon will reduce soil fertility and nutrient imbalance,and the soil microbial community structure will tend to be fungal,affecting the growth of muskmelon seedlings.The application of bio-organic fertilizer can effectively alleviate the obstacles of continuous cropping of muskmelon,improve the soil micro-ecological environment,promote the growth of muskmelon,and provide theoretical basis and guidance for the sustainable development of muskmelon planting industry.