| Typha L (Typhaceae), one of the most common aquatic plants found in marshes and shallow water, is almost cosmopolitan. However, the distribution of approximately20species has two main centers:Eurasia and North America. To date12species have been reported from China. According to the presence or absence of bracteoles The genus is divided into two sections:Ebracteatae groups and Bracteolate groups. Ebracteatae groups have4-5species in china. Although a lot of work has been done about the classification of Typha, none of uniform criterion is agreed by almost researcher in the taxonomy of T. laxmannii Lepech. and the distrbustion of T. przewalskii Skv. in china. Typha hybrid frequently, it has been reported in Europe and Americia, but hybrids has not repoted in our country.Based on literature survey, extensive field work and herbarium examination, the taxomical significances of the morphological characters were evaluated. Using the principle of biostatistics domestic and population conception, we studied the taxonomical problem of Ebracteatae groupin the level of individuals, inter-population, population and spcecies.The main results were as follows:1. Having checked the available specimens, we quantitatively analyzed the morphological characters in the relation to Ebracteatae group, and thus evaluated the taxonomical values in their taxonomy. we found that plant height, the distance between male and female inflorescence, the length of male and female inflorescence, the morphology of stigma, the length ratio of hairs and flower in Typha laxmanii have greater variation. In contrast, Typha orientalis and Typha latifolia are relatively stable. We found that plant height, leaf width, the distance between male and female inflorescence, the length of male and female inflorescence, the morphology of stigma, the length of hairs and flower and the morphological characters of pollen grians could be used to distinguish subsection or series, while the number of abortive flower have a relatively little value in taxonomical treatment of the genus. 2. We revised the species:T. orientalis Presl., T. latifolia Linn, and T. laxmannii Lepech., which were confirmed by scholars, and privided the keys of species of Ebracteatae group.3. We analyzed the morphological variation and its patterns of micro-morphological characters of reproductive organs which is of importance in taxonomic treatment at the level of individuals, spcecies, and population. The result showed that the morphological characteristics of sigma and vary and the length of haris and fertile flower in T. orientalis and T. latifolia have the relative stability, but the morphological characteristics of sigma and vary of T. laxmannii were cosiderable variability, in addition, they have a certain correlation; Between the different species, the morphological characteristics of sigma and vary and the length of haris and fertile flower ave the relative stability, then the length of fertile flower, hairs, style and gynophore and the location of vary in fertile flower ect. could not be applied in the classification of the genus.4. Typha*glauca Gordr.(T. angustioflia L. L.×T. latifolia L.), is reported as a new record to China. It is described in details. Morphological features of the hybrid and parental species was illustrated and discussed, and an identification key for them was provided. The hybrid was morphologically variable and generally intermediate to the parental species.5. T. laxmannii and T. gracillis are usually identified as a mistake in T. davidiana in domestic herbarium. Our research found that the former female flowers without bracts, stigma narrow obovate, then T. davidiana have spatulate bracts and stigma linear; The latter female flowers have bracts, hairs with swollen, globose apex, with sheath leaves, then T. davidiana without swollen, globose apex and sheath leaves. We discussed the relationship of T. laxmannii, T. davidiana and T. gracillis, and explored the distribution of T. przewakskii and T. changbaiensis. |
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