Sterile Germination of the Hybrid Seeds of [Den. Burana Green Star × Den. Rainbow-compactum] and Rapid Propagation of F_1 Plantlets via Tissue Culture

[Objective] This study was to germinate the hybrid seeds of [Den.Burana Green Star × Den.Rainbow-compactum] under aseptic condition and to explore the parameters for rapid propagation of F1 plantlets via tissue culture.[Method]Hybridization between Den.Burana Green Star（female parent）and Den.Rainbow-compactum（male parent）was performed and the in vitro culture and proliferation of F1 hybrids were studied using eight different basic media including MS,1/2MS,1/3MS,1/4MS,B5,N6,modified Knudson and H.[Result]Improved Knudson medium appended with 1.0 mg/L 6-BA,1.0 mg/L NAA and 10% mature banana puree performed best in F1 seed germination under aseptic condition,as well as the rapid propagation of protocorm-like body.Of all the eight media tested,1/2MS is the medium most suitable for the in vitro rapid propagation of the F1 seedlings.Efficiency of eight media in the in vitro rapid propagation was in order 1/2 MS MS1/3 MS1/4 MS ≈N6 improved Knudson ≈B5H.NAA presented better rooting and growth-promoting effect in the in vitro rapid propagation of the F1 seedlings than IBA.And the optimal NAA concentration to recommend from our experiment results was 2.0 mg/L.[Conclusion]Our experimental results provided mature method and important technological information for hybrid breeding dendrobium.

Sterile Germination of Dendrobium chrysotoxum Seeds and Rapid Propagation of Its Plantlets

[Objective] This study was to produce plant seeds on a large scale via sterile germination of the capsules of Dendrobium chrysotoxum and rapid propagation technique.[Method] A large amount of protocorm-like bodies produced from the sterile germination of D.chrysotoxum capsules,were transferred to four different kinds of bud induction media to obtain the optimal media suitable for plantlet differentiation and growth;and then with N6 as basic medium,1.0,1.5 and 2.0 mg/L of NAA and IAA were tested to obtain the optimal media suitable for rooting.[Results] On the medium of MS appended with 1 mg/L 6-BA ＋10% banana puree ＋ 20 g/L sucrose ＋6 g/L agar＋1 g/L AC,seed germination rate was up to 90%.The optimal medium for differentiation of D.chrysotoxum protocorm-like bodies was N6＋ 2 mg/L NAA ＋ 0.5 mg/L 6-BA ＋10% banana puree ＋ 20 g/L sucrose ＋ 0.5 g/L peptone ＋ 5.8 g/L agar ＋0.5 g/L AC,grown from which the plantlets were even and orderly in height;and the optimal medium for rooting was N6＋1.5 mg/L NAA ＋10% banana puree ＋ 20 g/L sucrose ＋ 5.8 g/L agar ＋1 g/L AC,grown from which the plantlets developed more,robust and orderly roots,and their leaves were in dark green color.[Conclusion] Our results provided reference for the rapid propagation of D.chrysotoxum.