Study On Pollen Morphology Of Plants From Taiyue Mountains,Shanxi Province

Pollen morphology is the basis of Palynology study.The study on the pollen morphology of modern plants can provide valuable reference for the study of plant phylogeny.At the same time,the study on pollen morphology and ecological environment that they indicated can be used as reference for the identification of stratigraphic pollen and prediction of paleoclimate and paleoenvironment by the sporopollen assemblage.Pollen morphology of selected taxa from the Taiyue mountains,Shanxi province in China are investigated in the present study.158 species(155 species and 3 varieties)of 128 genera belonging to 43 families were described and illustrated under light microscope(LM)and scaning electron microscopy(SEM).Pollen morphology in different genera of the same family,different species of the same genera,and different regions of the same species were also discussed in this study.Observation and description on pollen morphological characteristics of these species are important keys to the identification of fossil pollen grains of related taxa.At the same time discusses the paleoenvironment implications of pollen grains of the Taiyue mountains flowering plants and primary pollen types of the family Pinaceae and Asteraceae,which is significant for estimating the palaeoclimate,paleaoenvironment and climate change by utilizing the fossil pollen of the plants.Pollen morphological characteristics of the taxa studied in Lamiaceae are compared and discussed on the basis of systematic implications.(1)Pollen morphological characteristics of gymnosperm:This paper observed a total of 4 gymnosperm,belong to Pinaceae.Two are from the genus Picea and the other two belong to the genus Pinus.Pollen size was from 67.5?m(Pinus bungeana Zucc.ex Endl.)to 102.9?m(Picea wilsonii Mast.).Their surface texture was micreticulate in the body,and reticulate in the bladders.(2)Pollen morphological characteristics of angiosperm:In the study,154 species(151 species and 3 varieties)of 126 genera belonging to 42 families were examined.The results show that pollen grains were nearly subspheroidal(60.4%)and prolate(26.0%),and also contain spherical,oblate,perprolate etc.P/E values of Smilacina japonica A.Gray were the maximum(2.05),and that of Circaea alpina L.was the minimum(0.71);The maximum pollen grain is Lilium lancifolium Thunb.(117.5x62.3?m),and the minimum pollen grain is Spiraea salicifolia L.(14.8x11.9p?m).Aperture type is mainly 3-colpate and 3-colporate with a percentage of 42.9%and 14.3%respectively,and also contains 3-syncolpate,2-syncolpate,panporate,pantocolpate,3-colporate,6-colpate,single-colpate,3(-4)colporate,4-colpate etc.The surface ornamentation is mostly microreticulate,granulate and spinulose with the percentages of 36.4%,16.2%and 15.6%respectively.Other exine ornamentations,such as reticulate,striate-perforate,retipilate,'microspinulose,microspinulose-granulate are also observed.(3)Pollen morphological characteristics of Labiatae:Pollen morphology of 13 taxa belonging to 11 genera of the subfamilies:Ocimoideae,Scutellarioideae,and Lamioideae from China.Detailed pollen morphological characteristics are provided for these taxa.Among the studied taxa,Salvia umbratica Hance from the subfamily Lamioideae possesses the largest ones,and Elsholtzia densa Benth.from the subfamily Lamioideae have the smallest pollen grains.The pollen grains are shed as monads.The basic shape of the pollen grains in most taxa is oblate,subspheroidal or prolate.Pollen grains are radially symmetric and isopolar in all the taxa.The grains are hexacolpate or tricoipate.Two distinct exine sculpturing types exist,bireticulate(type?)and micreticulate(type ?).The bireticulate sculpturing patterns can be divided four subtypes and micreticulate can be divided two subtypes based on the detailed configuration of the exine ornamentation.