Taxonomic Revisions Of Salix Sect. Denticulatae Schneid. From Pan-Himalayas

Denticulatae Schneid. is one section of Salix with ca.30 species in China. It’s mainly distributed in Southwest of China. It’s also distributed in India, Nepal, Sikkim. Due to the complexity of habitat of most species in this section, the intraspecific variation is a big problem to our research. Meanwhile the distribution of different species overlaps eachother, which leads to hybridization between species. As Salix are dioecious, the female flower, male flower and leaf open at different time, so we can’t see all the characters of individual or one species at the same time. Besides we are lack of the investigation of Sect. denticulatae in Pan-Himalayas and surrounding area. So the number of herbarium are absent. Which leads to the difficulty of research, So the taxonomic revisions of Sect. denticulatae become more and more difficult.Throughout studying over 4000 sheets of species from more than 10 herbaria all over the world, and researching the previous references comprehensively, as well as the field work. Under the microscope, we can get results that the ovary stalk length, the hair of female flowers bract, the hair of male flowers bract, fhe shape of male flowers bract, the hair of filament, the shape of leaf, the hair of petiole are the valuable characters for species classification through the statistical analysis. Studying the leaf epidermal microfeatures of 32 Salix Sect. denticulatae of China under scanning electronic micoscope. The morphology of outer stomatal ledge and the wax layer, as well as the stoma morphology are the stable characters to classify the similar species, Which can be used as the basis to taxonomic revision of Salix Sect. Denticulatae Schneid. from Pan-Himalayas.Based on all the studies above, the taxonomic treatment was given in Pan-Himalayas and surrounding areas. Merging 3 species and disposing 1 varietas. Finally 25 species and 3 varieties were accepted.4 keys to the species of Salix Sect. Denticulatae Schneid. based on leaf epidermal microfeatures, characters of female plants, characters of male plants, vegetative characters are presented. The revised descriptions, maps of distribution and the key to every species were provided in this postgraduate paper.The result of this paper is also the taxonomic revisions of Salix Sect. Denticulatae Schneid. from Pan-Himalayas was carried on the requirements of writing Flora of Pan-Himalayas and edited in English. The studies will also be the preliminary achievement of Flora of Pan-Himalayas(Salix Sect. Denticulatae Schneid.)...