Analysis Of Phellodendron Amuranse Community Diversity And Its Alkaloid Content Regulated By Nitrogen And Phosphorus

This study investigated plant diversity of Phellodendron amurense community in the region of northeast China,focusing on the relationship between soil nutrients and different growth types of plants.We discussed the influence of alkaloid content in the tree by soil and climate factor,effect of photosynthesis and alkaloids content by nitrogen and phosphorus in seedlings and mature trees.The influence of environmental factors on Phellodendron amurense community plant diversity and its secondary metabolites were explored comprehensively,provided effective scientific basis of Amur cork tree resources protection in northeast China and forest medicine industry rapid development.(1)Through the investigation we found that Ulmus japoical,Syringa reticulata,Philadelphus schrenkii,Eleutherococcus senticosus,Cardamine leucantha,Filipendula palmata,and Meehania urticifolia etc.often appear more in Phellodendron amurense community’s structure;The rule of index of richness,Simpson,Shannon-Wiener of different plant growth types in 9 samples were herb>shrub>tree,index of Pielou was tree>shrub>herb;The structure of plant community in Weihe,Antu,Daxinggou,Fengcheng,Xinbin and were similar.The main limiting factors for the distribution of herb communities were all the chemical indexes except total phosphorus(2)The highest content of berberine,palmatine and jatrorrhizine in root bark of 9 samples were Antu,Weihe and Daxinggou,respectively;The highest content of berberine,palmatine and jatrorrhizine in stem bark of 9 samples were Hegang,Daxinggou and Hulin,respectively.The content of berberine and jatrorrhizine in root bark were significantly higher than that of stem bark,the content of palmatine in root bark was opposite,jatrorrhizine content in root bark and stem bark was significant negative correlation.This study also analyzes the correlation of soil nutrient factor and alkaloid content.The organic matter content in soil was significant negatively correlated with the berberine content in stem bark;Soil total nitrogen and available nitrogen content were significant negative correlated with the palmatine content in root bark;Soil available phosphorus content were significant positive correlated with the berberine content in root bark.Climate factors can also influence the alkaloid content of the tree.The annual mean temperature and precipitation were significantly positive correlated with the contents of berberine in root bark;Average temperature was significantly positive correlated with the contents of palmatine in root bark;Sunshine duration was significantly positive correlated with the contents of palmatine in root bark,(3)From the above results,level of nitrogen and phosphorus in soil is an important factor to influence alkaloids in Amur cork tree,through artificial simulation method to research the effect of seedling growth,photosynthetic characteristics and alkaloid content of the tree by different nitrogen and phosphorus levels.Under different nitrogen concentrations,the LSP and AQY are from high to low order:N8＞N2＞N16＞N0,Gs and Tr were N8＞N2＞NO＞N16.Nitrogen supply can significantly affect the PSII photochemical efficiency of seedlings,under different nitrogen supply levels,Fm.Fv/Fm and Fv’/Fm’ of seedling’s leaf were highest when nitrogen content was 8 mmol L-1 means that PSII photochemical efficiency was highest.Absence of nitrogen supply,PSII electron of recipient side transfer chain of the seedling’s leaf was blocked,ability to accept electron in PSII of recipient side reduced.But its main inhibitory effect site mainly occurred in the electron transfer process of QA to QB,means that abilitie to accept electron of QB was reduced,and influence was relatively small by PQ library.Absence of nitrogen supply,relative variable fluorescence of K and L point of the seedling’s leaf increased significantly,means at this time the activity of OEC restrained and stability of thylakoid membrane structure also decreased.The biomass of the seedlings under different level of nitrogen accumulation was significantly different.Aboveground and underground fresh and dry weight was the lowest in no nitrogen supply,and the plant diameter and root length was significantly lower than the other nitrogen treatment.Opposite to the growth,aboveground,underground and whole plant’s berberine,jatrorrhizine and palmatine content of the seeldings were all lowest when nitrogen content was 8 mmol·L-1,indicated that nitrogen is favorable to the growth of Amur Corktree but not conducive to the synthesis of 3 alkaloids.(4)According to the rectangular hyperbolic model,the photosynthetic parameters of Pn-PFD response curves under different phosphorus concentrations,the LSP and AQY are from high to low order:P1＞P2＞P0.5＞P0.1,Gs and Tr were P1＞P2＞P0.5＞P0.1.Fmand Fv/Fm were lowest under phosphorus content was 0.1 mmol·L-1,indicating that activity of PS II reaction center in seedling’s leaf significant decreased.Opening degree of PS II reaction center in seedling’s leaf was significant lower when phosphorus content was 0.1 mmol·L-1 than under other phosphorus content.The reason was under phosphorus content were 0.5,1.0 and 2.0 mmol·L-1,NPQ of the seedling’s leaf was higher.High NPQ can effectively dissipate excess light energy,but the mechanism of the dissipation of excess light energy through the initiation of NPQ in the seedling’s leaf was destroyed,the same reason is explained by the change of YNpQ.Under phosphorus content was 0.1 mmol·L-1,the mechanism of excess light energy dissipation depends on the cycle of xanthophyll,when non radiative energy dissipation mechanism was damaged,through the form of deactivation of PS Ⅱ reaction center and heat energy to dissipation of excess light energy.Aboveground or underground’s biomass and 3 kinds of alkaloids content in the seedling were reached highest value when phosphorus concentration of 1.0 mmol·L-1.There was no effect of synthesis of 3 alkaloids when phosphorus stress.But the affected by the seedling biomass,yield of berberine,jatrorrhizine and palmatine per plant with the increase of phosphorus content,first increased and then decreased.