Tissue Culture Of Syringa Reticulata Var. Mandshurica

Our purpuse of this study is to develop a method of seed breaking dormance and establish a in vitro culture system for Syringa reticulata var. mandshurica. A tissue culture system was established by shoot proliferation and callus culture approaches. Histology of tissue cultured materials were observed and analyzed.Seeds of S. reticulata var. mandshurica used in vitro culture were stratified with wet sand for 0, 20 and 40 days at 4#, then incubated to medium in 3 cutting treatments of intact middle-cut two ends-cut. The results showed that germination percentage of cut seeds was enhanced, middle-cut was the best treatment and achieved maximum germination after 10 days culture; germination of the seeds treated 40 days was better than the seeds with other-two treatments. In vitro germination of seeds with 40 days treatment was best on MS medium supplemented with BA 5 mg L-1 or BA 5 mg L-1 IBA 0.1 mg L-1.Plant regeneration from in vitro cultured plantlets derived from in vitro germinated seed of S. reticulata var. mandshurica was studied .The results showed that shoots could be induced with MS medium; the optium combinations of hormones was BA and IBA. The satisfied combinations were BA 5 mg L-1 +IBA 0.1 mg L-1, BA 5 mg L-1+IBA 0.5 mg L-1, BA 7 mg L-1 +IBA 0.1 mg L-1, and BA 7 mg L-1 +IBA 0.5 mg L-1, the corresponding shoot-induction frequencies were 73.5%, 75.0%, 64.5%, 60.8% respectively. The optium concentration of sucrose for shoot-induction was 2%. The plantlet could developed well after rooting in half strength MS medium supplement with 1 mg L-1 IBA .Different concentration of BA plus NAA or IBA combinations were tested on hypocotyls and young infloresence for callus induction. Most green loose and crisp callus were observed. The higher frequency of callus induction from hypocotyls was found in the combinations of BA 1 mg L-1 and 3 mg L-1 plus NAA 2 mg L-1, the corresponding callus-induction frequency was 80%~100%. The higher frequency of callus induction from young inflorencences was observed especially in presence of IBA plus BA. Satisfied effects were obtained in the combinations of IBA 0.1 mg L-1-0.5 mg L-1 plus BA 5 mg L-1- 8 mg L-1.Moreover, histological of callus and shoot from different explant was studied. The results showed the calli of hypocotyls and infloresence mainly originated from cortex parenchyma cells. Shoot genesis was also observed...