Adventitious bud formation in vitro from mature zygotic embryos of Pinus tabulaeformis Carr.

In order to determine the optimal conditions of inducing adventitious buds from mature embryos of Pinus tabulaeformis Carr., the mature embryos used as explants were respectively inoculated on TE, DCR and MS media to induce adventitious buds to find the best basal medium. According to uniform design U*6(64), the adventitious bud induction was analyzed by adding different concentrations of 6-BA,NAA and KT on TE basal medium. Based on the above experiments, further studies of the effects of sucrose concentration on the induction of adventitious buds and those of 6-BA on the growth of adventitious buds were carried out. The results showed that the basal medium played a determinative role in initiating adventitious buds. TE was the best, followed by DCR, and MS was the worst. Data processing, regression analysis and test optimization were completed using the Uniform Design Version 3.00 software. The optimal combination of growth regulators choice was 6-BA 6 mg/L+NAA 0.1 mg/L, and there was a lack of significant difference for KT. When the sucrose concentration was 4.0%, there was the highest rate of adventitious buds. Lower concentration of 6-BA was in favor of elongation of adventitious buds. The average length of adventitious buds was longest when using TE medium supplemented with 0.5 mg/L 6-BA and 0.1 mg/L NAA.