Tree Roses are also known as Rose standards, having a vertical tree trunk (0.8-1.5 meters high) of unbifurcation. Generally scented rose, miniature rose or other rose cultivations are grafted on the top of the stem to constitute the crown. Through gardening methods (cutting, the raising of root and stem, grafting, pruning etc.) tree-like roses are produced for garden making and decoration.Tree Rose has a long cultivation history abroad . In China it is a new darling of the garden landscape, with broad application prospects. Nowadays our Tree Rose has many shortcomings such as tender, low output and poor viewing. It will be effective if we find the solution to the development of Tree Rose by studying abroad rose tree cultivation methods and the problems existing in our own production. Based on the domestic and foreign research of tree rose rootstocks, production and application ,we can breed and improve tree-rose stocks and nurturing our tree rose stock for commercial production of high-quality.'Xue Shan Jiao Xia' bred by Ma Yan and Chen jun yu from a large number of hybrid progeny of breeding in 1992 through distant cross-breeding. Its parents were 'Snow White' and NO.8401. 10 years' cultivation observation proved that it was good when considering the beauty of flowers, strong resistance, healthy growth, strong vertical and thickened good growth and natural tree outline can be formed. Effects of several factors such as types of explants, and plant growth regulators on in vitro culture and rapid propagation of 'Xue Shan Jiao Xia' were investigated in detail in the present dissertation. The buds from the middle of the branches were the optimal explants. The optimal medium of initial is MS medium supplemented with 6-BA 0.5 mg/L.The rate of sprouting was up to 96.1% ,The explants differentiated a large number of young buds on MS medium containing 6-BA 1.0 mg /L , NAA 0.05 mg /L and GA32.0 mg/L. On this medium shoot multiplication occurred at a 5.2-fold rate after 40 days and the shoots were healthy. Shoots were rooted on the 1/2 strength MS medium supplemented with IBA (0.1-0.3mg / L)and the rate of rooting was 95%. |