Study On Graminera Flora In Jiangsu And Leaf Anatomical Characteristics Of Setaria

Gramineae plants in Jiangsu were studied by the method of combining the filed investigation with indoor experiment in this paper.Flora,plant resources,plant communities and leaf anatomical characteristics of different populations and different species of Setariain Gramineae were analysed.The main results are as follows:1.The study found 188 species belonging to 87 genera of Gramineae in Jiangsu,including 29 species in 10 genera of bamboo subfamily,159 species in 77 genera of agrostidoideae.Among them,Echinochloa,Phyllostachy,Roegneria,Eragrostis,Setaria and Digitaria dominated the group,holding 6 genera of 47species,accounting for 25.00%at the level of species in this area.There were 4 species of 3 genera plants of Jiangsu provincial new records,which were Roegneria hondai,Roegneria varia,Imperata koenigii and Melicascabrosa var.puberula.The floristic geographical elements of Jiangsu were complicated.The proportion of tropical and temperate elements increased significantly from genus,showing transitional characteristics from temperate to subtropics.The peculiar Chinese elements were poor with 2 species of 2 genera,accounting for 2.47%.2.There were 133 species of wild plant resources of Gramineae in Jiangsu,accounting for 70.74%of all the species.According to the economic use,they could be classified into six kinds:medicinal plants,edible plants,ornamental plants,environmental protection plants,forage plants and wood plants.Forage plants were the most important resources among them.3.The main community types of Gramineae in Jiangsu were bamboo forests,shrub,grassland and herbaceous swamp.At terms of plant communities,the paper analysed various communities of Phyllostachys pubescens,Phyllostachys viridis Phyllostachys glauca,Bambusa multiplex,Echinochloa crusgalli,Pennisetum alopecuroides,Roegneria kamoji,Phragmites australis,Arundo donax and Zizania latifolia.4.The paper indicated that there were 14 species of 12 genera alien invasive plants of Gramineae in Jiangsu,most of which were herbs.What's more.these invasive plants were widely distributed in Jiangsu,mainly under forest or in grassland and roadside.The invasion of Gramineae was serious in Yancheng and Lian Yungang,which was more than 8 species.The main reason was that the two cities were port cities with frequent personnel exchange and port transportation for the propagation and spread of invasive species.5.In order to explore the differences in leaf epidermal and anatomical characteristics among different species in Setaria,the paraffin section and the freehand section methods were applied for five Setaria species.The results showed that the leaf epidermal and anatomical characteristicsof five species were identical.And the pattern of anticlinal walls,the shape of stomatal subsidiary cells,the scale of prickle hairs and other characteristics could be used to identify species.6.To reveal the differences of leaf anatomical characteristics of Setaria viridis,the paper did researches on leaf variations among 15 populations.The results showed that 17 anatomical characteristics in different populations were of rich variations.Among these characteristics,thickness of midrib and abaxial epidermis owned the largest coefficient of variation.The thickness of leaf,the height and width of vascular bundle,the thickness of bulliform cell and the stomata density increased gradually among populations on the waterside and in alkaline land,wasteland and mountainous region,while the stomata size decreased in order.These results were of great importance to the ecological adaptability of S.viridis.