Study On Rapid Propagation Of Phalaenopsis Virus-free Plantlets In Vitro

Phalaenopsis is commonly called moth orchid because its flowers strongly resemble moths, which owns great market value. The most common means of asexual propagation is tissue culture. Cymbidium mosaic virus (CyMV) and Odontoglossum ringspot virus (ORSV) are the economically most important viruses that affects the health and quality of orchid plants. The study on elimination of CyMV and ORSV has great significance.In this study, Phalaenopsis strain "Dtps. Leopard Prince" plantlets as materials, we first established the tissue culture system of the strain, which the flower stalk buds as explants. Then, We used chemical treatment as virus elimination method, the proliferation buds of Phalaenopsis which infected with CyMV and ORSV were used as test materials, by adding different virus inhibitors in proliferation medium to select the more effective inhibitors. The study aimed at resolving the problem during Phalaenopsis virus-free plantlets rapid production to provide a scientific evidence and technical basis. The main results are as follows:(1) The results showed that in the medium of3.0mg/L Hyponex No.1+3.0mg/L BA+0.3mg/L NAA+20g/L sucrose, the axillary buds of floral stalk could be induced to germinate well. By dark culture for the first7days can reduced the browning effectively.(2) The proliferation test of adventitious buds were conducted by using L16(44) crossing and dealt with the basic medium, BA, NAA and sucrose factors. The consequences suggested that the most important factor affected the adventitious buds proliferation coefficient is BA, NAA and the basic medium followed by, and sucrose weakest. The medium of MS+8.0mg/L BA+0.8mg/L NAA+20g/L sucrose showed the best effects and the proliferation coefficient that can reached to2.83. The best organic compounds on adventitious buds proliferation is banana. Cutting adventitious buds into two buds without the leaves can increase the proliferation coefficient.(3)3.5mg/L Hyponex No.1+0.3mg/L NAA+0.3mg/L IAA+0.5mg/L MET+20g/L sucrose was the optimal medium in rooting stage. The AC added amount should not exceed1g/L, or may not add. Sucrose can significantly influence the growth of plantlets,20g/L is the suitable concentration. The best medium for transplantation was moss with the survival rate of transplanting up to93.18%.(4) Amino-oligosaccharin is an ideal plant virus inhibitor, with tihe CyMV and ORSV elimination rate reached up to83.33%and66.67%respectively. And ribavirin took second place with elimination rate of83.33%(CyMV) and50%(ORSV); the Chinese Herbs had the worst effect in detoxification.