Effects Of Cultivation Measures On Yield And Quality Of Polygonatum Cyrtonema Hua Under Forest

Polygonatum cyrtonema Hua is a perennial herb of Liliaceae,which is used as rhizomes and is a large medicinal herb in China.In recent years,with the increasing medicinal and health care value of Polygonatum cyrtonema Hua,the demand for the raw materials of this drug has become much larger,and the high price has greatly stimulated the excavation of Polygonatum cyrtonema Hua by the medicinal herb collector.As a result,the unplanned collection of wild Polygonatum cyrtonema Hua increased,resulting in the depletion of wild resources accelerated,the amount of resources decreased year by year,unable to meet the needs of the market.Artificial cultivation is an effective way to solve this problem,but in the cultivation process of different producing areas,due to the differences in planting patterns and cultivation management measures?such as planting density,fertilization type,harvesting period?,the quality of Polygonatum cyrtonema Hua has been seriously affected.As a kind of shade-tolerant plant,Polygonatum cyrtonema Hua is well-developed in a relatively shade environment and is more suitable for bionic plantation under forest.However,the bionic cultivation technology of Polygonatum cyrtonema Hua under forest is still imperfect at present.Therefore,the optimum cultivation techniques for bionic planting of Polygonatum cyrtonema Hua,by evaluating the growth amount,the yield of medicinal materials and the changes of pharmacodynamic active ingredients of Polygonatum cyrtonema Hua under the different conditions of fertilizer combined application,planting density,light transmittance and so on,will be found in this study,which can provide technical support for the benign development of essence industry on Polygonatum cyrtonema Hua.The main research results are as follows:?1?The field experiment was carried out by using the"3414"random block design to study the effect of N,P,K on agronomic traits,yield and effective medicinal ingredients?including total polysaccharide,total saponin,total flavonoids,saponins,diosgenin content?of Polygonatum cyrtonema Hua under forest.And this study could establish the fertilizer effect model of Polygonatum cyrtonema Hua and estimate the best yield and fertilizer application rate in Chongqing.The results showed that the yield of Polygonatum cyrtonema Hua increased first and then decreased with the increase of single fertilizer dosage.The main elements limiting yield was N>K>P,and N,P,K promoted each other with the interaction effect of NP>PK>NK.The nitrogen application significantly promoted the accumulation of total polysaccharides and total flavonoids.The phosphorus application increased the content of diosgenin,And the potash application increased the total saponins and diosgenin content.According to the establishment of the ternary quadratic effect function,the optimum economic fertilization amount of N in Chongqing was 179.23 kg·hm^-2,P₂O₅was 127.875 kg·hm^-2,K₂O was 88.601 kg·hm^-2,and the optimum economic yield was 3227 kg·hm^-2.And the revenue was 96810 yuan·hm^-2 excluding the fertilizer cost.?2?The proportion of organic and inorganic fertilizer applied in biomimetic planting under Polygonatum cyrtonema Hua forest was determined.A field experiment was conducted to study the effects of different proportion of organic pig manure combined with chemical fertilizer on the yield,quality,main enzyme activity in soil,available nutrients and culturable microorganism quantity of Polygonatum cyrtonema Hua.The results showed that the combined application of organic pig manure and chemical fertilizer had a significant effect on the yield and quality of Polygonatum cyrtonema Hua,and the highest yield of rhizome was obtained when the proportion of organic fertilizer was 75%,which was 50.88%and 33.21%higher than that of no fertilization?CK?and single fertilization?T0?respectively.When the proportion of organic fertilizer was 50%,the total polysaccharide content of Polygonatum cyrtonema Hua was increased by 50.02%,31.58 and 11.97%,10.34%,respectively,compared with that of no fertilization?CK?and single fertilization?T0?.Combined application of organic fertilizer could decrease the number of fungi and increase the number of bacteria in soil,and single organic fertilization?T4?could significantly increase the number of soil bacteria,which was 85.14%and 71.25%higher than that of no and single fertilizer treatments respectively.There was no significant difference in the number of actinomycetes among the treatments.Combined application of 75%organic fertilizer could significantly increase the activities of urease,sucrase,dehydrogenase,acid phosphatase and the content of available nutrients in soil.The results of correlation analysis showed that the rhizome yield,total polysaccharide content,total saponins content were significantly positively correlated with soil available nutrients,soil urease,sucrase,dehydrogenase,bacterial number and actinomycete number,rather negatively correlated with soil catalase and the number of fungi.In a word,combined application of 50%to75%organic fertilizer could improve the yield and quality of Polygonatum cyrtonema Hua more favorably.?3?The suitable planting density of biomimetic planting under Polygonatum cyrtonema Hua forest was determined.With the increase of planting density of Polygonatum cyrtonema Hua,the plant height,ground diameter and biomass per plant tended to decrease.When the row spacing was25cm×25cm,the yield per unit area was the largest,which was 2.54 times higher than that of M10treatment?35cm×60cm?.However,the contents of total polysaccharides and total saponins in M1and M2 treatments were significantly lower than those in other treatments.There was no significant difference in the contents of total polysaccharides,total saponins and total flavonoids among M3 to M10 treatments.Therefore,the best planting density was 25cm×40cm.?4?The suitable range of light transmittance of biomimetic planting under Polygonatum cyrtonema Hua forest was determined.With the decrease of light transmittance,the ground diameter of Polygonatum cyrtonema Hua decreased gradually,the plant height,single leaf area,total biomass,root shoot ratio and yield increased first and then decreased.When the light transmittance was45.7%,the plant height,single leaf area,stem biomass and leaf biomass had the maximum value.Under the condition of 68%light transmittance,the root shoot ratio and yield had the maximum value,which was 38.296%higher than the total light yield.With the decrease of transmittance,the total polysaccharide content of Polygonatum cyrtonema Hua increased first and then decreased,and the total polysaccharide content had the highest value when the transmittance was 45.7%.The content of total saponins was negatively correlated with the transmittance,while the content of total flavonoids was positively correlated with the transmittance.The yield of polysaccharide,as the evaluation index,was significantly higher than that of other treatments under the light transmittance of 68.4%and 45.7%.Therefore,the optimum light transmittance was 68.4%to 45.7%in the condition of planting Polygonatum cyrtonema Hua under the forest.