The Comparison On The Differences Of Characteristics Of Agronomy And Physiology And Biochemistry In Different Polygonatum Germplasms

In order to screen the germplasm of Polygonatum?Polygonatum cyrtonema Hua?,the aim is to provide scientific basis for breeding and high-efficiency cultivation technology of Polygonatum.In this study,22 germplasm resources of Polygonatum were collected from Hunan and its surrounding counties?cities and districts?as research materials.So that they can be planted under the same cultivation environment.Through the plant leaf length,leaf width,leaf length to width ratio,leaf thickness,leaf number,leaf shape factor and leaf area,plant height,stem diameter,root fresh weight and dry weight,stem fresh and dry weight,leaf fresh weight and the dry weight,fruit diameter,seed length,seed width and thickness,100-grain weight,root length,average root diameter,maximum root diameter,and root minimum diameter were compared for agronomic traits.The relationship between chlorophyll content,net photosynthetic rate,transpiration rate,stomatal conductance,chlorophyll fluorescence parameters and other main photosynthetic characteristics,and the relationship between the content of polygonine polysaccharide and the geographical climate factors of its origin were analyzed.The relationship between the diurnal variation parameters,the light response curve and its parameters,the CO₂ response curve and its parameters and the geographic and climatic factors in the origin of the 6 germplasms were also analyzed.The main results are obtained as follows.1.The phenotypic characteristics and biomass of Polygonatum with different provenances were significant?P>0.05?or very significant?P>0.01?.Among them,plant height,leaf width,fruit diameter and 100-seed weight were highly heritable,they were71.0338%,57.1567%,63.3212%and 77.8334%,respectively,and its coefficient of variation was less than 10%.It was controlled by middle genetic system,which was not easy to be influenced by environment.However,the heredity of the root morphologic characteristics is generally weak.All of them were below 30%,and their coefficient of variation was relatively high,which was greatly influenced by environment.The index of aboveground partsuch as leaf thickness,leaf number,leaf area,plant height and stem diamete,was significantly positively correlated with the underground root.2.Geographical and climatic factors of different Polygonatum germplasm agronomic traits and provenance has significant or highly significant correlation,the leaf length and dimension and temperature in July reached a significant level of positive correlation of biological,Leaf number,seed length,seed width and frost-free period was significant positive,Plant height,root length and seed thickness respectively with altitude and?10?reached a significant level of positive correlation.3.The diurnal variation of photosynthetic characteristics of different varieties of Polygonatum sibiricum showed a single peak curve,the peak values of Pn,Gs,Ci,WUE and Ls all appeared at 10:00 in the morning.The peak value of Tr appears at 12:00,and Pn drops at midday.The indexes of photosynthetic characteristics of AH,SZ and LP of Polygonatum are relatively low,which are mainly restricted by stomatal factors.However,the photosynthetic characteristics of Polygonatum germplasm XF,XS and SZ were relatively low,mainly due to the limitation of their mesophyll cell activity.The comparison of Pn-PAR curves of different Polygonatum germplasms showed that the photosynthesis of XF in Polygonatum germplasm had stronger adaptability to environment and had stronger photosynthetic capacity.LP and AH have moderate photosynthetic capacity.The photosynthetic capacity of XS,SZ and LX was weak.Pn-Ci response curves of different varieties of Polygonatum showed that the photosynthetic capacity of Polygonatum could be effectively improved by increasing CO₂ concentration.The LP,SZ,XF and AH of Polygonatum had strong activity of photosynthetic enzyme.The Polygonatum germplasm LP has greater photosynthetic potential.4.The differences of chlorophyll a,chlorophyll b and total chlorophyll content of different varieties of Polygonatum sibiricum were significant?P<0.05?or extremely significant?P<0.01?,and the average values of chlorophyll a,chlorophyll b and chlorophyll content were higher in different Polygonatum germplasms,it shows that it has a wide adaptability to the environment.The content of chlorophyll b in germplasm was quite different,indicating that their genetic variation was more abundant.The chlorophyll fluorescence characteristics of different varieties of Polygonatum showed significant or extremely significant difference among germplasm.Among them,Fv/Fm was less than 0.75,It indicates that CX,HH,LX and XS have good adaptability to local climate.5.The content of polysaccharides in Polygonatum collected from different cultivars showed significant or very significant difference.Among them,the average value of Polygonatum polysaccharides from 22 germplasms reached above 7%of standard,and all reached the Chinese pharmacopoeia standard.However,the germplasm of AH,XF,LS,SM,ST,YS,YL1 and YD had no standard plants in Polygonatum,and their coefficient of variation was relatively high.The content of Polygonatum Polysaccharide was unstable,which can be used for further selection breeding.The content of Polygonatum polysaccharide YL2,GZ,XP and SZ was relatively stable among plants.Therefore,its germplasm can be used as the promotion and application of medicinal Polygonatum.The correlation analysis between agronomic characters of Polygonatum and polysaccharide content of Polygonatum.The growth of Polygonatum was too large or too small,which will hinder the accumulation of Polygonatum polysaccharides.The correlation analysis between the content of Polygonatum polysaccharides from different germplasms and the geographical climatic factors in the source area showed that the lower accumulated temperature had the accumulation of Polygonatum polysaccharides of Polygonatum.6.The main component analysis of the agronomic characters,photosynthetic characteristics and the content of Polygonatum polysaccharides of different germplasms showed that the 22 germplasms could be divided into 9 types.The growth factor of the first principal component F1 was the largest,which was 29.388%and its characteristic root was8.816.It can accurately reflect the characteristics of various characters of the different germplasm,and was the most similar to the comprehensive rankings,and the JS performance was best in the comprehensive rankings of different germplasms.