Study On Key Cultivation Techniques Of Panax Notoginseng Rotation Of Polygonatum Kingianum Under Forest

Polygonatum kingianum is a perennial herb of the genus Polygonatum in the family Liliaceae.As the medicinal and health value of Polygonatum kingianum is gradually known,the wild resources of Polygonatum kingianum are exhausted and difficult to meet the market demand.At the same time,another precious Chinese herbal medicine Panax notoginseng also has serious continuous cropping obstacles,which leads to the land shortage of Panax notoginseng after planting a stubble,which seriously restricts the sustainable development of Chinese herbal medicine industry.The results showed that reasonable rotation could realize the recycling of land,and the growth conditions of Polygonatum kingianum and Panax notoginseng were similar.Therefore,this study intends to alleviate the problem of’taboo land’caused by continuous cropping obstacles of Panax notoginseng and promote the healthy development of Polygonatum kingianum industry by rotating Polygonatum kingianum in the forest land that has been planted with Panax notoginseng.However,the literature on the cultivation techniques of Polygonatum kingianum in the rotation of Panax notoginseng under forest has not been reported.Therefore,this experiment deeply studied three key cultivation techniques of Polygonatum kingianum in rotation.Different soil amendments were applied to treat the soil before planting,different root dressing agents were used to treat the seedlings,and different density treatments were set up during planting,in order to seek a set of suitable rotation of Polygonatum kingianum under forest.The key cultivation techniques of Polygonatum kingianum.The main research results are as follows:(1)The suitable soil amendment and concentration of Polygonatum kingianum were determined.The experiment of setting different types and concentrations of soil amendments showed that different soil amendments had little effect on the emergence rate and growth index of Polygonatum kingianum in the early stage.In the middle and late stages,it could significantly reduce the incidence of root rot and improve the survival rate of Polygonatum kingianum.Using plant ash C2(900 kg/hm~2)and C3(1200 kg/hm~2),quicklime S2(900kg/hm~2)to improve soil had the best effect on controlling root rot,and the incidence rate was less than 4%in September.The annual yield of Polygonatum kingianum cultivated on the ground of P.notoginseng under the forest improved by plant ash C3(1200 kg/hm~2)was the highest,reaching 5158 kg per hectare,which was 1585 kg higher than that without soil improvement.Different soil amendments had no significant effect on the effective components of Polygonatum kingianum under forest rotation.Compared with the soil before and after physical and chemical cultivation,it was found that the p H value,conductivity and available potassium content in the soil increased,while the organic matter,alkali-hydrolyzed nitrogen and available phosphorus content in the soil decreased significantly.Therefore,the application of three soil amendments can effectively prevent the occurrence of root rot of Polygonatum kingianum,improve the survival rate,alleviate soil acidification and improve nutrient utilization.Among them,the improvement effect of plant ash C3(1200 kg/hm~2)is the best.(2)The optimal root dressing treatment formula for rotation of 2-year-old Polygonatum kingianum in Panax notoginseng under forest was determined.The results of different root dressing formula experiments showed that Polygonatum kingianum under different root dressing treatments could significantly improve the emergence rate and survival rate of Polygonatum kingianum,promote the growth of Polygonatum kingianum,and effectively prevent the occurrence of root rot.In September,the incidence of root rot of Polygonatum kingianum under no root dressing treatment reached 54.25%,while the incidence of root rot under SF1 and SF2 root dressing was only 4.75%.Under the SF1 root dressing formula,the yield of Polygonatum kingianum was as high as 4756 kg/hm~2 after one year of cultivation under the forest,which was 172%higher than that under no root dressing treatment.The content of polysaccharides and total flavonoids in Polygonatum kingianum was also the highest,reaching 9.5%and 1.5 mg/g.The results showed that the growth and quality of Polygonatum kingianum were the best under the root mixing formula of SF1(80%tetramycin powder+5%thiram+15%captan),and the comprehensive effect was the best.(3)The suitable planting density of Polygonatum kingianum was preliminarily determined.By setting different cultivation density experiments,the results showed that with the increase of planting spacing,the incidence of root rot of Polygonatum kingianum under the forest decreased,the emergence rate and seedling survival rate increased,and the content of total saponins and total flavonoids increased.The plant height,fresh and dry weight of the main root were the largest and the growth was the best under the row spacing M4(40×45 cm).However,with the increase of planting spacing,the number of plants per mu was gradually reduced,and the yield of Polygonatum kingianum was also reduced.The yield of Polygonatum kingianum with M1(20×25 cm)was as high as 6343 kg per hectare after 1year of cultivation under the forest.Compared with M4(40×45 cm),it increased by 4362kg.The results of planting Polygonatum kingianum for one year under the forest showed that under the background of pursuing yield and economic benefits,it was most suitable to select M1(20×25 cm)to cultivate Polygonatum kingianum.In summary,before the cultivation of Polygonatum kingianum,soil improvement and root dressing treatment measures can effectively reduce the incidence of root rot of Polygonatum kingianum,increase the survival rate,and increase the yield of Polygonatum kingianum.The effect of applying 1200 kg of plant ash per hectare on the soil moisture surface is the best,and the growth effect of Polygonatum kingianum under the root dressing formula SF1(tetramycin powder 80%+thiram 5%+captan 15%)is the best.Polygonatum kingianum was cultivated under the forest for one year,and M1(20×25 cm)was the most suitable planting spacing.In general,after one year of cultivation of Polygonatum kingianum,its effective components did not change much,but it could effectively alleviate soil acidification,and the nutrient content in the soil gradually decreased.Therefore,it was necessary to provide nutrients for Polygonatum kingianum in time in the later stage.These studies provide technical guidance for the rotation and planting of Polygonatum kingianum in Panax notoginseng under forest,and provide new measures to solve the problem of avoiding land caused by continuous cropping obstacles of Panax notoginseng.