Study On Ecological Suitability Regionalization And Origin Evaluation Of Amomun Tsaoko

In order to develop and utilize the A.tsaoko,the current situation of the resources was investigated comprehensively.The high-quality provenances were selected from the collected resources,and the chemical components were analyzed.The correlation between the volatile oil content and environmental factors was analyzed,and the change law of chemical components in different stages of fruit development and drying degree was explored.In 2019,16 regions of Yunnan and Guangxi were investigated.Based on species distribution information,combined with maximum entropy model and geographic information system,the suitable production areas were analyzed.Meanwhile,15 fruit characters of 57 germplasm resources were evaluated;high quality resources were selected and chemical components of high quality production areas were determined by GC-MS;climate information of sampling points was extracted.The p H value,organic matter,hydrolyzed nitrogen,total phosphorus,effective phosphorus and total nitrogen were determined according to national soil standards.The correlation analysis and stepwise regression analysis were used to analyze the correlation between volatile oil content and environmental factors.The four samples from August,September,October and November were collected and dried at 50℃for 48 hours,and the samples from the same month were dried for different hours(0,12,24,36,48 hours).Then the components and contents of volatile oil were analyzed by GC-MS.The results are as follows:(1)The results of the maximum entropy model show that the geographical distribution range of A.tsaoko is 99.1-112.8°E、20.5-30.4°N,and the area of highly suitable area were48.14×104 Km~2;mainly distributed in Yunnan,Guizhou,Sichuan and Western Guangxi;among the climatic factors,the precipitation in June,the standard deviation of seasonal temperature change,seasonal variation coefficient of precipitation,annual average temperature,solar radiation in October and the dry monthly precipitation have a great influence on the geographical distribution of the species;the resource survey shows that Yunnan is the main production area of A.tsaoko.The habitat difference between the producing areas forms a variety of planting patterns of A.tsaoko:⑴Alnus nepalensis forest+Amomum tsaoko;(2)Cunninghamia lanceolata forest+Amomum tsaoko;(3)Juglans regia forest,Camptotheca acuminata forest,or Toxicodendron vernicifluum forest+Amomum tsaoko;(4)The mixed primeval forest+Amomum tsaoko;(2)The phenotypic data analysis showed that there were abundant phenotypic variation patterns,and the average coefficient of variation of 15 characters was 27.34%.Among all the characters,the coefficient of variation of volatile oil yield was the largest(53.54%).The correlation analysis showed that there was a strong correlation between fruit characters.According to clustering analysis 57 resources were divided into seven categories,includingⅠ,ⅢandⅤclass containing different origins.The results of principal component analysis showed that five principal components accounted for 80.53%of the total,which could explain most of the information of the characters.18 excellent resources were selected,especially the fruit of Gongshan County,Nujiang.The volatile chemical components of the high-quality producing areas were different,and the chemical components with higher content were similar,such as(E)-3,7-dimethyl-2,6-octadienal,nerolidol 2;(3)The results showed that the content of volatile oil was positively correlated with precipitation in June,positively correlated with organic matter,positively correlated with total nitrogen and hydrolyzed nitrogen,and negatively correlated with p H.Stepwise regression analysis showed that soil organic matter was the main factor affecting the content of volatile oil;(4)During different stages of the growth,Compounds were detected respectively 17,26,24 and 19.It mainly contains one kind of ether,seven kinds of alkenes,six kinds of aldehydes,six kinds of alcohols and two kinds of aromatics.During the drying process,the peel thickness and weight of the fruit showed a downward trend,with the most obvious decrease from 12 to 24 hours,and the kernel weight changed more smoothly.The yield of kernel volatile oil increased linearly,with the highest yield of 2.72 ml/g at constant weight in 48 hours.A total of 38 compounds were identified in the kernel,and the yield was 2.72ml/g at constant weight of 48 hours.26,23,21,22 and 26 components were detected in the first stage,including sixteen kinds of alkenes,seven kinds of aldehydes,three kinds of aromatics,one kind of ether and eleven kinds of alcohols;the content of(1R)-(+)-α-pinene decreased to be undetected due to different drying degree.The relative percentage content of 1,8-cineole and other active components increased first and then decreased;the content ofα-oenanthene decreased first and then increased,and the peak value appeared at 48h(4.71%);the relative percentage content of ortho-neoldehyde remained unchanged.These above results provide a theoretical basis for revealing the geographical distribution characteristics of A.tsaoko resources,reasonably planning the planting area,and screening high-quality A.tsaoko resources.And these results also have guiding significance for the harvesting and processing of A.tsaoko.