Preliminary Study On Cross Of Rosa Cvs. And Rosa Rugosa And Resistance To Black Spot Of Rose

Rose (Rosa cvs.) is one of the most important cut flowers in the world. It has always been beloved because of perpetual bloom, diverse patterns and rich colors. Modern rose have many varieties, but some of them are odorless and insufficient resistance for plant disease and insect pest, which has seriously affected the yield and quality of Rose. Rosa rugosa has aromatic flavor and good resistance for plant disease and insect pest, so it is believed a good material for breeding. It is hoped that the good character of aromatic flavor and resistance would be shift in hybrid by cross breeding between Rose and Rosa rugosa, and new rose cultivars could be cultivated with our own independent intellectual property. Black spot of rose, as one of the major diseases of Rose, is a worldwide disease. The method of leaf vitro infection could screen rapidly the resistant plant, which is a convenient way to provide the foundation for finding the breeding materials for resistance and to evaluate the resistance of hybrids.The results are shown as follows:1.55 hybridized combinations were designed.1430 flowers were pollinated, and we obtained 346 fruits, 3467 seeds and 201 plants of the hybridized progenies. According to broad cross, ten groups of cross combination were chosen which had high hybridization compatibility.2. The 5 F1 hybrids were identified using the SSR molecular marker process and morphology identification. The result showed that two of them are true hybrids.3. Identified the resistance of the black spot in 48 rose varieties using leaf vitro infection, four varieties of high disease resistance, eight of medium disease resistance and nine of low resistant varieties were selected.The study provided the experience for cross breeding with rose and Rosa rugosa. The hybrids of Rosa cvs. XRosa rugosa could be materials selected for new cultivars. It also laid the basis for cultivation of new rose varieties with our own independent intellectual property. The method of leaf vitro infection could provide a foundation for choosing the black spot resistant varieties of rose.