Vivipary in Ophiorrhiza mungos L. - a rare phenomenon in angiosperms

Abstract

Vivipary, the precocious germination of seeds within the parent plant, is a specialised feature of evolutionary and biological importance that ensures survival of a plant. Reports on vivipary in angiosperms are rare, accounting for <0.1% of flowering plants. Here, we report a remarkable case of occurrence of vivipary in Ophiorrhiza mungos. A study was conducted to collect information on the morphology of the capsules that support vivipary, environmental factors that induce vivipary, survival mode and the survival of viviparous seedlings. The hydroscopic movement of the cup-shaped capsules of O. mungos was found to help in viviparous germination during the rainy season. Of the total seeds in a capsule, 70% showed viviparous germination. The seedlings remaining inside the capsule attain a height of 0.98 ± 0.4 cm and reach the ground when the capsule falls. On the ground, seedlings obtain easy anchorage to the substratum since they have already germinated. Vivipary appears to be an adaptation of O. mungos to the rainy season for ensuring viable offspring. This suggests that vivipary in this species might be artificially induced by continuous spraying with water to rescue seeds in all seasons for use in large-scale propagation to meet increasing market demand and conservation of this valuable anticancer medicinal herb.

Keywords: Camptothecin; Ophiorrhiza mungos; Rubiaceae; capsule; vivipary.