Study On The Flora In Guizhou/southern Sichuan And Phylogenetic Problems Of Impatiens L.

In this paper,the author studied the flora of Impatiens L.in Guizhou and southern Sichuan,including structure and distribution of Impatiens species,floristic features and characteristics,and origin et al.And also studied the palynology and molecular phylogeny of Impatiens species.The main results are summatized as follows:1.Species structure and distributionThere are 71 Impatiens species and barieties in Guizhou and southern Sichuan,27.3% of the total species in China,7.1% of the total species in the World.Except the widely cultivated species of Impatiens balsamina L.?the tropical Asia distribution of Impatiens chlorosepala Hand.-Mazz.,Impatiens chinensis L.?the temperate Asia distribution of Impatiens radiata Hook.f.and the East Asia distribution of Impatiens infirma Hook.f.,the rest 66 Impatiens species and varieties are endemic to the China(accounting for93.0% of the total species).However,13 species are endemic to Guizhou(accounting for 18.3% of the total species),and 19 species are endemic to southern Sichuan(accounting for 26.8% of the total species).In Guizhou and southern Sichuan,there are distributed ancient endemic species of Impatiens wilsonii Hook.f.,also distribute some evolution of Impatiens species of Impatiens sigmoidea Hook.f.et al.which they are new endemic species.Vertical distribution of the Impatiens species is evident in Guizhou and southern Sichuan,and they distribute between 300 m and 3200 m alt.but mainly distribute between 800 m and 2800 m alt.There are 62 Impatiens species(accounting for 87.3% of the total species).2.Floristic composition and propertiesBased on the comprehensive analysis of Impaties species distributioncharacteristics ? geographical features,especially the floristic features in Guizhou and southern Sichuan,the Impatiens flora of Guizhou and southern Sichuan can be divided into 5 types of 15 distribution types from Chinese seed plants flora : they are widespread species(Impatiens balsamina L.);tropical Asia species(Impatiens chlorosepala Hand.-Mazz.and Impatiens chinensis L.);temperate Asian species(Impatiens radiata Hook.f.);east Asia species(Impatiens infirma Hook.f.)and Chinese endemic species(66Impatiens species,such as Impatiens liboensis K.M.Liu et R.P.Kuang?Impatiens guizhouensis Y.L.Chen?Impatiens chishuiensisY.X.Xiong?Impatiens gasterocheila Hook.f.and Impatiens omeiana Hook.f.at al.).This shows that Impatiens flora in Guizhou and southern Sichuan possesses tropical to temperate transition.Morphological traits of Impatiens in Guizhou and southern Sichuan including sepal number,fruit shape,inflorescence type,flowers number and floral morphology et al.Possess more diversity.Base on the analysis of Impatiens species traits and characteristics of diversity,evolutionary relationship especially the specific nature of endemic species,the diversity of Impatiens flora in Guizhou and southern Sichuan,not only shows that the Impatiens flora is ancient,but also shows this region should be center of the Impatiens distribution and differentiation of China,it plays an important station in Impatiens flora of China and even World.3.Study on palynology of Impatiens speciesThe pollen morphology of 29 species of Impatiens species has been examined under SEM.The results show that the pollen grains are goniotreme,actinomorphic or zygomorphic,reticulate exine ornamentation.the equatorial view is oblong,nearly round or rectangular oval;the polar view is oblate.the size of pollen grains is medium size,23.8-39.6 ×13.5-29.8?m.3-colpate or 4-colpate.Among the observation of material,the speciesof 3-colpate germination aperture such as Impatiens wilsonii etc may be an original group,the featureare is radial symmetrysize;while the species of4-colpate germination aperture such as Impatiens bodinieri etc may be evolutive group,the featureare is actinomorphic or zygomorphic.In4-colpate Impatiens species,pollen shape,size,surface ornamentation are different.The Impatiens species can be classified on the basis of morphology,especially the granule characters of exine ornametation,these features can provide some proof for indentification of some species in Impatiens.4.The research of molecular Systematics in Impatiens L.The nrDNA ITS and cpDNA atpB-rbcL of 29 species,which represent most of the morphological types,were sequenced.Based on these two sequences,five phylogenetic trees are constructed using Hydrocera triflora as out groups,the Impatiens phylogenetic tree show that Balsaminaceae is a monophyletic,and Hydrocera triflora located in the root of phylogenetic tree is sister to Impatiens.In this study,29 Impatiens species can be divided into five major clades.CladeI locates the root of phylogenetic tree,these species are perennial herb,four lateral sepals and 3-colpate pollen et al.This group should be the primordial Impatiens group in Guizhou and southern Sichuan.CladeII is inflorescences having numerous flowers(more than 4 flower).Clade III is spindle or wide spindle fruit.Clade IV is petals have filamentous structure.CladeV is total pedicels obvious,few flowered racemes,usually no more than 3 flower(rarely 3 roses).The information,whether the classification of the Impatiens,or the evolutionary relationship,phylogeny and origin,are great significance.5.A new discovery of endangered Impatiens species populationIn E'bian county,Impatiens gasterocheila was collected by Hooker in1910.However,no one has collected the field individual species from1910 to 2014.Fortunately,we found the wild living plants in southern Sichuan in the summer of 2012.After further investigation,we found that the number of I.gasterocheila is very small populations,which be in the endangered species.And it is only 2 populations of wild populations at present,the number of individuals less than 500 species,so it can be identified as "endangered species endemic to China which facing high extinction risk".This discovery will recognize that the Impatiens species will be endangered genetic diversity and the structure of the endangered mechanism.It is important significance to restore populations of endangered Impatiens species,and it also has effective protection.6.New discovery of floraIn this study,the author found a new species(Impatiens liboensis K.M.Liu et R.P.Kuang published in Nordic Journal of Botany,SCI,2014.).And also found 13 new record species of Impatiens in Guizhou and southern Sichuan.There are Impatiens wilsonii Hook.f.?Impatiens duclouxii Hook.f.? Impatiens cyathiflora Hook.f.? Impatiens siculfeir Hook.f.var.porphyrea? Impatiens aquatilis Hook.f.?Impatiens uliginosa Franch?Impatiens commellinoides Hand.-Mazz.? Impatiens longialata Pritz.ex Diels?Impatiens platychlaena Hook.f.?Impatiens davidi Franch.?Impatiens nanlingensis A.Q.Dong et F.W.Xing?Impatiens fragicolor Marq.et Airy Shaw and Impatiens tomentella Hook.f.So the information of Impatiens flora and germplasm of China are enriched at great extent.