| The Qinghai-Tibetan Plateau has the richest diversity of alpine plants in the world and is a center of distribution and differentiation for taxa such as Arenaria,Silene and Meconopsis.Not only the genera Arenaria and Meconopsis are important part of the alpine flora of the Qinghai-Tibetan plateau,but their ’cushion structure’ and ’thorny structure’ are typical adaptations among the alpine plants of the plateau.Molecular phylogenetic studies indicate that the genera Arenaria and Silene are not monophyletic and that the subgenera from Arenaria are to be raised to genera level,but morphological evidence is insufficient.A large number of new species of the genus Meconopsis have been published by scholars with relatively weak morphological differences,and molecular phylogenetic studies have not been able to distinguish between these new species and their relatives,and subgenus classification of Meconopsis is urgently needed.The seed micromorphology is taxonomically important,but there are research gaps in the genera Arenaria,Silene and Meconopsis.To solve the problem of unclear attribution and confusion over the names of the three genera.This paper intends to study a total of 43 species,10 subspecies and 7 varieties of 83 seeds of five genera,including Arenaria,Silene and Meconopsis,through literature review,field survey and specimen identification,using scanning electron microscopy(SEM),of which 38 species,6subspecies and 6 varieties are studied for the first time,with a view to providing new morphological evidence for the systematic classification of the three genera,and the main conclusions are as follows:1.The diverse morphology of the seeds of the Caryophyllaceae family,which exhibit an extremely rich array of micromorphological characters,supports the raise of several subgenera of the genus Arenaria to the genus level.The genus Silene,Eremogone,Dolophragma and Odontostemma show some differences in seed morphology,which are taxonomically significant and may provide new evidence for the systematic classification of the family.Seed micromorphological evidence supports a closer phylogenetic relationship between the Thylacospermum and Dolophragma.The evolutionary relationships within the Odontostemma are complex and may not be a natural group,and it would be hasty and undesirable to package and raise the subgen.Odontostemma directly to the genus level.The type of seed coat ornamentation and shape of the seed coat cells are better taxonomic value for the genus Silene.The genera Odontostemma and Silene were inadequately sampled,and future sampling needs to be expanded to better resolve taxonomic relationships within the genus.2.Seeds of the genus Meconopsis are rich in micromorphological features and show some variation among the subgenera,which have some taxonomic significance.Seed micromorphology,especially seed coat ornamentation,has good taxonomic significance for closely related species.Several closely related species can be effectively identified,such as the M.horridula complex and the M.integrifolia complex.Combining field observations,morphological studies,geographic distribution and seed micromorphological evidence,the investigators concluded that the infraspecific division of M.wilsonii and M.balangensis was not reasonable.3.Seed morphological characters are relatively stable.Differences in seed maturity can result in differences in fullness and micromorphology.Future research needs to be combined with the examination of type specimens,field observations,extensive sampling,seed micromorphology,sporopollenology and molecular systematics,and only then the systematic classification of the genera Arenaria,Silene and Meconopsis can be systematically resolved. |
