Tissue Culture And Growth Observation Of Callistemon Glaucus

Callistemon glaucus (Bonpl.) Sweet, endemic to Australia and belonging to Myrtaceae, Callistemon is one kind of bottle brush trees which are famous for their Bottle- brush-like flowers. It is an excellent landscape tree species with high daptability and high ornamental and phamseutic value.Tissue culture of this tree species was conducted with tender stem segments and leaves as explants to provide bases for rapid propagation system. And, based on the introduction cultivation, the growth rule of Callistemon glaucus in Wuhan were observed as well. Main results were as following:(1) In establishing an aseptic system of stem segments with buds, it was best to pick up explants from April to May, sterilze the explants with 0.1% HgCl2 for 8 minutes, which a sound results of 31.11% pollution percentage and 46.67% germination percentage could be obtained.(2) Murashige and Skoog (MS) medium supplemented with 6-BA (1.0 mg/L)and NAA(0.01mg/L) was found to be most effective in initial culture, and the germination rate was 83.33% and average shoot hight was 1.99cm. Optimum shoot proliferation was established when shoots were subcultured on WPM medium containing a 3.0mg/L 6-BA and 0.05mg/L NAA, and the proliferation coefficient was 1.64. Rooting was achieved in 1/2 MS medium complemented with 0.25mg/L IB A and 30g/L sucrose and the average roots length reached 2.98cm. The rooted plantlets were acclimated to outdoor conditions and established in pots containing garden soil with about a 80% survival percentage.(3) Good callus induction were obtained by culturing aseptic leaves in the medium WPM supplemented with TDZ (0.1 mg/L) and 2,4-D(1.0 mg/L), which callus induction rate reached 93.33% and calli growed well. 1.0mg/L 6-BA had good effect on callus differention with the highest average shoot number 15.0. Difficulties existed in callus proliferation and further research was needed.(4) Browning could be effectivle controlled by applying PVP in medium, and 500 mg/L PVP presented the best effect. But VC could result in deformity and restrain shoots from elongating and proliferating. (5) Callistemon glaucus grew well in nearly three years cultivation in Wuhan, and showed good ornamental traits. There were two growth peaks per year, and it grew fastest in spring. It also showed high adaptability to the environment in Wuhan, and could safely overwinter in the open.