The Systematical Studies On Species From Genus Machilus In Zhejiang Province

Machilus is a genus in the Lauraceae. Acoording to Flora Reipublicae Popularis Sinicae , there are 100 species in the world, and 68 species and 3 varities in China. There are 11 species in Zhejiang , and 2 species only distributed in Zhejiang Province.According to collected data, based on evidence from gross-morphology, anatomy, pollen - morphology, numerical taxonomy, molecular systematics, phytogeography and the feasibility of application in garden, the classification , the relationship of species from genus Machilus in Zhejiang and the value of the plants of genus Machilus practice was systematically studied in this paper, and provides evidence for exploitation and utilization. The main results are summarized as follow:1.gross morphologyOn the basis of field observation and examimation of herbarium specimens, the variation pattern of all the major gross- morphology characters in Machilus from Zhejiang was studied, and their taxonomic significance was evaluated. The results show that the most reliable characters for the delimitation of species are the features of the leaf, the tepal and the fruits. The secondly important characters are the length and position of the florescence. The third important character is the twig. The evolutional trendsof the twig, leaf, florescence, tepal and fruits were discussed.2. Anatomy of both leaf and lemma epidermis Micro-morphological characters of leaf epiderm is of 11 species and 1varities of Machilus distribute in Zhejiang were examined by LM and SEM. The results show that the characters such as shape and pattern of anticlinal walls of epiderm ,stomatal density,stomatal distribution and epidermal hairs possess the classific value of species. Most of these species had simple hairs. The stomatal apparatus is paracytic type with one or two subsidiary on both or either side of the guard cells. Three types of anticlinal walls of epidermal cells are recognized: straight, sinuolate or sinuate. The evolutional trends of the types of anticlinal walls of epidermal cells and epidermal hairs were discussed.3. Pollen morphologyPollen morphology of species from Machilus in Zhejiang was observed using SEM. The results indicate that pollen grains radially symmetrical , apolar, spheroidal, the exine with distinct spines and temuity or perforation, usually the spines very small and dense. There are mat-shaped thickenings at the base of spines in the certain species of Machilus. The most reliable characters for the delimitation of species are the features of the perforation, mat-shaped thickenings. The evolutional trends of the extine ornamentations in the pollen grains were discussed.4. Numerical taxonomyOn the basis of the morphology and palynology, 11 taxa were studied using the numerical taxonomy, on which relationship between the species were discussed. The results revealed that relationship among 34 characters used by the numerical taxonomy were relatively isolated.5.Molecular systematicsData obtained from RAPD technique significantly shows relationship between this species. The results were generally consistent with ones fromthe morphology and palynology.6. PhytogeographyThe geographic distribution shows the south of Zhejiang is the center of distribution of genus Machilus in Zhejiang. Mostly species inhabit of low elevations. Based on data from specimens, the distribution map of each species in Machilus from Zhejiang were given .7. Feasibility of applicationAccording to analysis the ornamental character, the ecology benefit and the economic value, the author considers there is a wide prospects practices of genus Machilus plants in Zhejiang , and it ought to be widen application and dissemination, also the practices of the plants of genus Machilus in Zhejiang in garden was discussed in this paper.Based on the above results, the genus Machilus from Zhejiang was taxonomically revised.: one species was increased as varities; one combinations was made. Thus altogether 10 species and 1 variety were recongnized.