黄瓜子叶节离体培养物花分化Ca^(2+)敏感期的研究(简报)

STUDIES ON CALCIUM SENSITIVE PERIOD DURING FLORAL DIFFERENTIATION OF CUCUMBER COTYLEDONARY NODE CULTURES IN VITRO

植物开花是一个非常复杂的过程,对其机理的研究有着重要的实践意义和理论意义。近百年来进行了广泛的生理生化研究,提出过多种假设。自90年代初成功分离了花器官分化和发育基因以来,使这一研究领域进入了分子水平。钙不仅是植物的矿质营养元素之一,而且Ca2+作为植物的第二信使,参与细胞内多种生理生化活动。许多研究结果表明,Ca2+在成花诱导、花芽形成和分化过程中起重要作用。

Cotyledonary nodes of cucumber cultured on calcium-free medium for 0, 1, 2, 3, 4, 5, 6d respectively, were transferred to medium with 6.0 mmol/L CaCl2 for 24h, then returrned to calcium-free medium. Cotyledonary nodes cultured on calcium-free or 6. 0 mmol/L CaCl2 medium for all time, were taken as controls. Results showed that Cotyledonary nodes were transferred to 6.0 mmol/L CaCl2 medium for 24h during 0 - 3d after the beginning of culture, percentage of floral bud formation at Cotyledonary nodes was increased significantly. Transferring Cotyledonary nodes on the 3d day after the beginning of culture was achieved best effect , percentage of floral bud formation was up to 34. 3 % . We deduced that the calcium sensitive period during floral differentiation of cucumber cotyleddonary node cultured in vitro may be 0 - 4d after the beginning of culture.