STUDIES ON ORGANOGENESIS FROM CULTURED MATURE ZYGOTIC EMBRYOS OF LOBLOLLY PINE
TANG Wei OU YANG Fan (State Key Laboratory of Biochemical Engineering, Institute of Chemical Metallurgy, Academia Sinica, Beijing 100080) GUO Zhong Chen (Institute of Botany, Academia Sinica, Beijing 100093)
Light yellowish loose glossy globular callus was initiated from mature zygotic embryos of loblolly pine (Pinus taeta L. ) cultured on TE medium supplemented with NAA and BA. After callus proliferation and the induction of adventitious buds were finished, the influences of phyto-hormones, low temperature treatment, and sucrose concentration on differentiation of adventitious buds were investigated. The results show that the highest differentiation frequency of ad- ventitious buds (62. 15%) was obtained on TE medium containing 0. 4 mg. L-1 IBA and 2 mg · L-1 BA. The optimum low temperature treatment time and sucrose concentration were 5-6 weeks and 25-30 g. L-1, respectively. After elongation culture shoots more than 1 cm in height were selected to culture on rooting medium. The highest rooting frequency (46%) were obtained on TE medium with IBA, BA, and GA3.