Effects Of Applying Different Organophosphate-degrading Bacteria On The Quality Of Paris Polyphylla And Soil Environmen

Paris polyphylla var.yunnanensis has the effects of anti-tumor,clearing heat and detoxification,and is in great demand in the market.However,its slow growth and development and long harvest cycle of finished products result in short supply in the market.At present,the technology and means of artificial cultivation of Paris polyphylla var.yunnanensis are not mature,the yield and quality are low,and it is easy to damage the soil environment.Phosphorus is one of the essential elements for plant growth and development,but the content of phosphorus in soil can be effectively used by plants is small.In the process of artificial cultivation,phosphorus fertilizer will be applied to ensure the growth and development of plants.The application of phosphorus fertilizer increases the risk of environmental pollution.Therefore,the purpose of this study is to improve the utilization rate of soil phosphorus by inoculating organophosphorus bacteria in the process of artificial cultivation of Paris polyphylla var.yunnanensis,so as to reduce the use of chemical fertilizer and reduce the risk of environmental pollution.In this study,three strains of organophosphorus decomposable bacteria with high phosphorus solubilization capacity were selected from rhizosphere soil of Paris polyphylla var.yunnanensis.The effects of organophosphorus bacteria on plant growth and development were investigated by the determination of leaf area,photosynthesis and physiological and biochemical indexes of the leaves of Paris polyphylla var.yunnanensis.The effects of quality of Paris polyphylla var.yunnanensis were investigated by measuring the content of total saponins and 6steroidal saponins.Through the determination of soil fertility index,phosphorus form and nutrient content in rhizosphere soil,the influence on rhizosphere soil environment in Paris polyphylla var.yunnanensis was investigated.At the same time,heavy metal pollution was evaluated by the content of heavy metal elements in the medicinal materials and soil.The results showed that the inoculation of organophosphorus bacteria could reduce the content of malondialdehyde in the leaves,improve the leaf area,photosynthetic parameters,photosynthetic pigment content,soluble sugar content,soluble protein content,and the activities of superoxide dismutase,peroxidase and catalase,and enhance the resistance to the environment.The soil microorganisms were enriched,and the activities of phosphatase,protease,sucrose and other soil enzymes were improved.Compared with the control group,the nutrient contents of available phosphorus,available potassium and alkali-hydrolyzed nitrogen in rhizosphere soil increased by 51.64%,45.88% and 181.46%,respectively,which greatly improved the rhizosphere soil fertility.The biomass and saponins content of rhizome and stem of Paris polyphylla var.yunnanensis were increased.The total amount of 6 steroid saponins increased by 132.56%,and the total saponins content increased by 33.68%,which greatly promoted the improvement of medicinal quality of Paris polyphylla var.yunnanensis.It promoted the absorption and utilization of soil phosphorus by the plant,enhanced the enrichment ability of P,K,Mg,Mn and other elements in the medicinal parts of the plant,and effectively improved the utilization rate of soil elements in the plant.In addition,the inoculation of organophosphorus bacteria can effectively reduce the contents of Hg,Pb and Cr elements in the medicinal parts of Paris polyphylla var.yunnanensis.Except for the soil pollution risk in some treatment groups,the rest of the treatment groups all reached the clean level,and the heavy metal content in the medicinal parts of Paris polyphylla var.yunnanensis did not exceed the standard limit value.Among all treatment groups,the combination of Bacillus mycoides,B.proteolyticus(S5)and B.mycoides、B.wiedmannii and B.proteolyticus(S7)had the most obvious effect on the growth and development of Paris polyphylla var.yunnanensis.The combination of B.mycoides、B.wiedmannii and B.proteolyticus(S7)had the best effect on improving soil fertility.The combination of B.mycoides、B.wiedmannii and B.proteolyticus(S7)had the strongest effect on the quality of Paris polyphylla var.yunnanensis.Single inoculation of B.proteolyticus(S3),and the combination of B.mycoides 、 B.wiedmannii and B.proteolyticus(S7)had the strongest effect on improving the utilization of phosphorus and the adsorption capacity of nutrient elements.The combination of Bacillus mycoides and B.proteolyticus(S5)could effectively reduce the content of heavy metal elements in Paris polyphylla var.yunnanensis medicinal materials.In conclusion,the inoculation of organophosphorus bacteria can effectively promote the growth and development of the plant,improve the rhizosphere soil environment,and improve the quality of the medicinal materials.The effect of composite inoculation is stronger than that of single inoculation,and S7 treatment group has the best benefit of combination of strains.This inoculation method can be considered to be applied in the large-scale artificial planting process of Paris polyphylla var.yunnanensis,which can not only improve the production efficiency of Paris polyphylla var.yunnanensis,but also reasonably protect the ecological environment.