Study On Key Technologies Of Safe And Efficient Production Of Artemisia Selengensis

Artemisia selengensis is a characteristic vegetable in China.Since the 1990s,it has been planted in greenhouses in southern China on a large scale,making important contributions to increasing farmers’income in the main producing areas.However,because the planting time of Artemisia selengensis is short,its industry still has a large space for improvement.Moreover,Artemisia selengensis has the characteristics of enriching heavy metals,and there are hidden dangers for consumers to eat.Therefore,the integration of safe and efficient production and cultivation technology is very important for the sustainable development of industry and the health of consumers.This experiment studied the effects of different soil conditioning substances and the amount of organic fertilizer on the yield and quality of Artemisia selengensis and cadmium accumulation,soil p H and cadmium content,and the effects of cutting,winter heat preservation/warming on the growth and quality of Artemisia selengensis.Moreover,this study summarized the practical planting experience of Artemisia selengensis in Hubei province and integrated a set of safe and efficient cultivation techniques.The main results of this paper are as follows:1、Safety production of Artemisia selengensis(1)Effects of different soil conditioning substances on Artemisia selengensis and soil.The application of Serratia,Bacillus subtilis,selenium tetravalent and biochar significantly reduced the content of cadmium in Artemisia selengensis,which could be reduced by 34.79%,33.25%,24.39%and 21.05%respectively.In addition,the application of Serratia,selenium tetravalent,silicate compounds and PGPR significantly increased the yield of Artemisia selengensis.Quicklime,selenium tetravalent,PGPR,silicate compounds,Serratia and biochar treatment could reduce the content of available cadmium in soil,at the same time there was no significant difference between treatments,and the reduction rate was 16.23%-27.15%.(2)Effects of application amount of organic fertilizer on Artemisia selengensis and soil.Organic fertilizer significantly increased the yield,VC and soluble protein contents,and decreased the content of cadmium.When the application amount of organic fertilizer was 2000kg/667m~2,cadmium content decreased by 47.64%and yield increased by49.50%.In addition,the application of organic fertilizer can affect the availability of cadmium in soil.When the application rate of organic fertilizer was 1500kg/667m~2,soil available cadmium content was significantly decreased by 12.69%compared with that without organic fertilizer.When the application rate was 3000kg/667m~2.(3)Differences of quality and Cadmium content in Different Artemisia selengensis cultivars.In the study,three types of Artemisia selengensis,including white pole,green pole and red pole,were collected.The contents of cadmium were significantly higher and soluble protein and soluble sugar of white pole were significantly lower than those of green pole and red pole.Moreover,there was no significant difference in cadmium content between green pole and red pole.2、The efficient production of Artemisia selengensis(1)Effects of cutting technology on production efficiency of Artemisia selengensis.The cutting part of Artemisia selengensis should choose the part of a stem near the top of semi-lignified branches,and its survival rate is the highest,which is 80.04%.The survival rate of the part of a stem near the root is low,so it should be discarded.Moreover,the survival rate was the highest when the length of cuttings was 15 cm and 20 cm.When the cutting depth was 1/2 of the soil,the survival rate was 91.90%.Otherwise,the efficient cutting production mode of Artemisia selengensis should choose 15cm long cuttings,and the cutting depth is 1/2 of the cutting length.(2)Effects of winter heat preservation treatments on the growth of Artemisia selengensis.Heat preservation treatments could significantly increase plant height,yield,soluble sugar content and decrease nitrate content.Two layers of film and one layer of non-woven fabric significantly increased plant height by 26.85%,yield by 16.93%and soluble sugar by 109.09%.At the same time,the nitrate content was reduced by22.69%-41.53%under heat preservation/heating treatment.3、Integration of key technologies for safe and efficient production of Artemisia selengensisIt is recommended to apply 1500kg/667m~2or 2000kg/667m~2organic fertilizer for base fertilizer.If the soil is acidic,quicklime can be applied to improve the soil p H(it is recommended to apply it every other year,60-75kg/667m~2).At the same time,Serratia(1.0*10~8cfu/g)or Bacillus subtilis(500g/667m~2)or tetravalent selenium(5mg/kg)or biochar(75kg/667m~2)are recommended to reduce the accumulation of cadmium in Artemisia selengensis.Moreover,for cutting of Artemisia selengensis,select the middle and upper part of the seedling stem,cut it into cuttings with a length of 15cm,and insert the soil to 1/2 of the length during cutting.In winter,covering the small arch shed with film or non-woven fabric in the greenhouse can improve the growth rate,yield and quality of Artemisia selengensis.4、Discuss the cadmium limit standard of Artemisia selengensisAt present,the cadmium limit standard of Artemisia selengensis is not unified in China.By consulting the cadmium content of Artemisia selengensis in various places,comparing the international and domestic food safety standards,and referring to the actual situation of cadmium content of Artemisia selengensis in the main production areas and markets of Hubei Province,this study puts forward that Artemisia selengensis should be classified as green leafy vegetables,and its cadmium limit standard is set to 0.2 mg/kg according to the standard of leafy vegetables.