关键词: 兰属, 象牙白, 种子, 茎尖, 组织培养, 形态发生

Abstract: A propagation method of Cymbidium eburneum var. parishii (Rchb. f . ) Hook. f . by in vitro culture of seeds and shoot-tips , and the morphogenesis of protocorms from the cultured seeds are described in this paper. The germination capacity of young seed was very low but became prominently higher when it reached five months old. Although seeds could germinate on basal medium , addition of coconut milk , or NAA and KT to the medium clearly stimualted the germination of seed. After germination , The embryos developed into PLBs, which latter multiplicated and differentiated into leaves and roots , to form complete plantlet . It took more than seven months for seeds to develop to plantlets after sowing. Protocorm2like bodies (PLBs) were induced from shoot-tip explants in MS medium supplemented with NAA 0. 1 mg·L^-1, BA 3. 0 mg·L^-1 and coconut milk 10 %. PLBs multiplicated in MS medium supplemented with NAA 0. 1 mg·L^-1 and BA 5. 0 mg·L^-1. Plantlets were induced from PLBs in the media without any hormone. Roots were induced in 1/ 2 MS medium supplemented with 7 % banana juice and 3 % potato juice. The multiplication rate of PLBs were influenced by different light intensity, culture state and pH value significantly.

Key words: Cymbidium, Cymbidium eburneum var. parishii (Rchb. f . ) Hook. f ., Seeds, Shoot-tips, Tissue culture, Morphogenesis