Study On Cuttings And In Vitro Culture Of Seven Jasminum Species

Jasminum belongs to Jasminoideae of Oleaceae.There are about 200 species of Jasminum all over the world.China shares more than 50 species of it and Institute of Flora,Guangxi Academy of Agricultural Science collects 36 kinds of plants which are mainly Jasmine sambac.Jasmine sambac belongs to the evergreen shrubs of Jasminum in Oleaceae or vines.There are a rich variety of Jasmine sambac.Jasmine sambac-based Jasminum is of great economic value,high ornamental and landscaping value.In recent years,researchers have carried out several research on Jasminum.The research focused on its classification and application while few involved study on cutting seedlings and in vitro culture.Moreover,the chosen samples are similar and not typical in the existing research on cutting seedlings and in vitro culture.Cuttings are the most commonly used methods of breeding Jasminum.Cuttings have many advantages like fast propagation speed and keeping excellent traits of cultivated plants.In terms of in vitro culture,it has fast propagation speed,large reproductive coefficient and can produce sterile seedling.However,it has always been difficult for woody plants to conduct in vitro culture.Also,there are few reports on the in vitro culture of Jasminum.In this study,Jasminum dichotomum will be taken as cuttings.The effects of different hormones and their concentrations,cuttings immersion time in hormones and different substrates on the rooting of Jasminum dichotomum cuttings will be discussed.And Jasminum sambac Grand Duke of Tuscan,Jasminum dichotomum,Jasminum nudiflorum Lindl and other seven materials will be taken as experimental materials for in vitro culture.The effects of different sterilization processing,the choice of different explants,media and hormone on in vitro culture will be discussed.The results can provide theoretical reference and technical guidance for main Jasminum sambac of Jasminum.The main results were summarized as follows:(1)To increase the number of living roots and rooting rate of Jasminum dichotomum cuttings,sand should be used as the substrate and the cuttings should be soaked in the mixture of IBA with the concentration of 250 mg/L and NAA with the concentration of 500 mg/L for 20 minutes.(2)As shown in the experiments of explants,among the seven kinds of Jasminum plants selected,Jasminum sambac Grand Duke of Tuscan,Jasminum dichotomum,Jasminum nudiflorum Lindl were more suitable materials for this in vitro culture test.The middle part of the stem section was the most suitable part for the explant material;May and June were the most suitable time for selecting the explant material.(3)The best method of sterilizing stem segments of Jasminum sanmbac was sterilizing the pretreated stem segments of Jasminum sambac with 75%alcohol for 30 seconds,and then using 0.1%HgCl2 for 16 minutes.In this way,budding rate of axillary buds,stem segments were the highest while the infecting rate and death rate were the lowest.(4)The stems of three plant materials like Jasminum sambac Grand Duke of Tuscan,Jasminum dichotomum,Jasminum nudiflorum Lindl performed best in the WPM+6-BA3.0 mg/L+NAA0.01 mg/L+IBA0.2 mg/L.The germination rate reached 91.43%,and the germination rate of the buds reached 34.31%.In the primary seedling proliferation culture,the best proliferation medium was MS+6-BA3mg/L+NAA0.01mg/L.The germination rate of bud seedlings reached 92%,and the growth rate of bud seedlings was fast,which could be subcultured many times.In rooting culture,the best medium for rooting culture of bud seedlings was 1/2MS+IBA0.8 mg/L.The rooting rate of the buds was 94%,and the average height was 8.22 cm.