Research Of Pinellia Ternata With Three Intercropping Patterns On Soil Micro-ecological Environment

Continuous cropping of Pinellia ternata would lead to a soil microenvironment deterioration,the plant diseases and insect pests get further aggravation,it would cause the low yield and quality in field production called continuous cropping obstacle.Study have found that intercropping can ameliorate the microflora,improve the soil nutrient and enzymatic activity,and it could be a effective measure to subduct the continuous cropping obstacle.The experiment was carried out to research the soil microorganism,nutrient and enzyme activity by Pinellia ternata planted with different intercropping crops.In order to find a reasonable intercropping crop to explore the feasibility through ecological cultivation to subduct the continuous cropping obstacle of Pinellia ternata and improve the yield and quality.Main results of this study were as follows:1.The Pinellia ternata-cultivating soil by different years,the quantity of bacteria presented a reducing trend,the largest in unplanted soil and the fewest in four years soil.the quantity of fungi presented a rising trend,the largest in four years soil and the fewest in unplanted soil.The soil changed from “ bacterial” to “fungal”.The reduction soil invertase,urease and acid phosphatase reached the significant level by the increasing years,the same as total nitrogen,available phosphorus,p H,total calcium and total zinc.2.The Pinellia ternata-cultivating by different intercropping patterns,the quantity of bacteria and actinomyce of Pinellia ternata monocropping were less than all the other 3 patterns.the quantity of fungi was more than the majority of intercropping patterns except Pinellia ternata‖konjak.Soil urease and acid phosphatase were the lowest in Pinellia ternata monocropping,and the invertase,polyphenol oxidase and catalase were at a low level.The content of total potassium and total phosphorus of Pinellia ternata monocropping were the most.the content of available phosphorus was just over Pinellia ternata‖konjak,the content of total nitrogen was the lowest.Total calcium,magnesium,sulphur and all microelement were no significant difference in different intercropping patterns.The soil fertility comprehensive score of Pinellia ternata‖soybean was the highest,Pinellia ternata‖pepper was the second,they might be the desirable intercroppingpatterns to release the continuous cropping obstacle of Pinellia ternata.3.Measuring the soil and rhizosphere soil of Pinellia ternata microflora in different intercropping patterns and different period,the experiment indicated that the bacterial diversity of soil and rhizosphere soil in middle period and rhizosphere soil in later period were the highest in Pinellia ternata‖soybean.The microbial diversity rhizosphere soil in later period was the highest in Pinellia ternata‖pepper.The fungal diversity still had a increasing tendency as time goes on,and Pinellia ternata‖pepper could release in a certain level.Intercropping had little influence to actinobacterial diversity.4.In the yield aspect,Pinellia ternata‖soybean showed the most productive,the first-class tuber and fourth-class tuber presented counter-balance,coupled with a high variation coefficient,so to boost the rate of first-class tuber through intercropping might be one of the effective ways to increase production of Pinellia ternata.In terms of quality,soluble protein and extract content were the highest in Pinellia ternata‖konjak.Soluble sugar,reducing sugar,butanedioic acid and guanosine content were the highest in Pinellia ternata‖pepper.Alkaloids content was the highest in Pinellia ternata‖soybean,but all variation coefficient of the quality index were at a low level.The comprehensive assessment of yield and quality by principal component analysis indicated that the comprehensive score of Pinellia ternata‖soybean was the highest,the Pinellia ternata‖pepper was the second,they might be the desirable intercropping patterns to high yield and quality cultivating methods of Pinellia ternata.5.The experiment had separated and cultivated 239 bacterial isolates from different soil and rhizosphere soil in different period.Then the experiment was carried out to found 36 bacterial isolates which could produce IAA through Salkowski colorimetric method.At last,germination test was carried out to screen for 3 bacterial isolates which possessed growth-promoting effect to Pinellia ternata bulbil.After molecular biological identification,3 bacterial isolates were Bacillus megaterium,Bacillus subtilis and Bacillus flexus respectively.