Study On Morphological Anatomy And Tissue Culture Of Forsythia Suspensa

Forsythia suspensa is a kind of perennial deciduous shrub. The resources of Forsythia suspensa are rich in China, mainly distributed in the loess plateau area in North China. And the areas with the most highest yield are Shanxi, Shaanxi, Henan and other places. Forsythia suspensa are not only excellent medicinal and ornamental tree species, with medicinal value and health effects, landscaping, soil and water conservation and ecological afforestation, but also the kind of plants used as edible pigment sources, honey and oil sources.The plants have broad prospects for development and application. In recent years, along with the increase of artificial afforestation, the pure forest area of wild Forsythia suspensa is reducing year by year, and the germplasm resources and production of medicines are continuously decreasing. The harvest in advance causes the waste of resources and a decline in the quality. It is of great significance for the sustainable development of pharmaceutical Forsythia suspensa to protect, develop and take advantage of excellent germplasm resources, to improve production and content of active components and to improve the level of standardized planting.In our experiment, we used Forsythia suspensa which was genuine regional drug in Shanxi Province as the object. The methods of botany and paraffin section technique were adopted to study on stems and leaves in vegetative organs and flowers and fruits in reproductive organs of Forsythia suspensa, to understand the morphological characteristics and microstructure characteristics of different types of Forsythia suspensa. With the application of plant tissue culture technology, we studied on micropropagation and anther culture of Forsythia suspensa to explore the feasibility of excellent germplasm enlargement and biotechnology breeding.(1)The result of the observation on the morphological and anatomical structure of stems and leaves of Forsythia suspensa showed that in the young stem,there was a round of vascular bundle, the vast majority of vessel elements was spiral. Pith maded of lots of parenchyma cells was in the the central of stem, between the pith and vascular bundle there was perimedullary zone composed of small cells with thickened cell wall.With the bold growth of stem of Forsythia suspensa, a lot of parenchyma cells bursted, the pith cavity was in the central of the stems after stems matured. The type of phyllotaxy was opposite, and there were three kinds of leaf shape such as the simple type, the two-leaf type and the three-leaf type. There were six arrangements in the branches for three types of leaves. After comparing the thickness of palisade tissue, the thickness of spongy tissue, the thickness ratio of palisade tissue and spongy tissue (P/S) and vein protuberant degree (VPD), the result displayed that in the three types of Forsythia suspensa leaves, the thickness of palisade tissue, the thickness of spongy tissue and P/S value of the three-leaf type were the maximum, but this had the lowest VPD.(2)The result of the observation on the morphological and anatomical structure of flowers and fruit of Forsythia suspensa showed that: â‘ Forsythia suspensa flowers from the campus of Shanxi University included the two normal types which were the normal short-styled Forsythia suspensa flowers and the normal long-styled Forsythia suspensa flowers, and seven kinds of mutated flowers which were the flower with three corolla lobes and two stamens, the flower with three corolla lobes and three stamens, the flower with four corolla lobes and three stamens, the flower with four corolla lobes and four stamens, the flower with five corolla lobes and two stamens, the flower with five corolla lobes and three stamens, and the flower with six corolla lobes and three stamens.â‘¡The common features of the two normal types which were the normal short-styled Forsythia suspensa flowers and the normal long-styled Forsythia suspensa flowers and the two kinds of mutated flowers including the flower with four corolla lobes and three stamens, the flower with four corolla lobes and four stamens were that inside and outside corolla surface of these flowers, there were many glands, faliments were hollow, ovary was two-loculed, the type of placenta was placentation axile, embryo was kidney-shaped; the different characteristics were that the healing degree of the diaphragm of the ovary in the four flowers was different, the stigma of the short-styled flower with three stamens was composed of three hemispherical projections, the rest were composed of two hemispherical projections.â‘¢In six types of Forsythia suspensa flowers from the drug cultivation farm located in Jiangxian in Shanxi province,we found that the morphological structure of anthers differed with each other, pollen sacs of these atrophied in different degrees, in one of the flowers, two anthers differed in size, shape and color, this was the heteranthery phenomenon.(3)The result of micropropagation of Forsythia suspensa showed that we initially established a rapid breeding method of Forsythia suspensa.At the stage of establishing a sterile culture system for Forsythia suspensa buds, the MS medium in which added 1.0 mg/L 6-BA and 0.1 mg/L IBA was the suitable medium; NAA in the medium could cause callus of buds. At the stage of shoot multiplication, the suitable medium were the MS medium in which added 1.0 mg/L 6-BA,0.2 mg/L KT,0.5 mg/L IBA and 30 g/L of sucrose and the B5 medium to which added 1.5 mg/L 6-BA,0.2 mg/L KT,0.1 mg/L IBA and 30 g/L of sucrose.(4)The result of anther culture showed that in the MS medium added 0.5 mg/L ZT,2.0 mg/L 2,4-D,500 mg/L CH and 80 g/L of sucrose and 6 g/L agar, anthers of the short-styled Forsythia suspensa flower with three stamens could form haploid callus after dedifferentiation.The above experimental results could provide an experimental basis for the study on the diversity of Forsythia suspensa resource and development, utilization and cultivation of excellent germplasm.