ENHANCEMENT OF PLANT FORMATION FROM EMBRYO CULTURES OF TAXUS MAIREI USING SUITABLE CULTURE MEDIUM AND PVP

摘要

Seedlings of Taxus mairei, of which seeds have proved difficult to germinate, were obtained by embryo cultures. Seed development in four stages was classified according to the visible characteristics of the fruits; viz, young fruits without aril, green fruits with undeveloped green arils, pink fruits with enlarging pink arils and mature fruits with fully developed red arils. The composition of the medium was the critical determinant. A 1/2MS medium with PVP supported the best embryonic growth and seedling development not only for T. mairei but also for T. baccata, T. canadensis, T. cuspidata and T. media. Only 15% of young embryos of T. mairei, in this medium, developed into plants. However, nearly ninety percent of embryos at green, pink, and mature stages developed into plants. A 90% survival rate of in vitro plantlets grown in the greenhouse was obtained.