Resumen de Pollination ecology of the coastal pantropical hermaphroditic shrub Scaevola taccada (Goodeniaceae)
A.J. Solomon Raju, Kunuku Venkata Ramana, Banisetti Dileepu Kumar
Scaevola taccada is a coastal evergreen bushy shrub. It blooms throughout the year but intense flowering occurs only during the wet season. The flowers are fan-shaped, bisexual, protandrous, nectariferous, selfcompatible and display a secondary pollen presentation mechanism, which principally facilitates crosspollination while keeping the option open for self-pollination. Flower foragers include bees, wasps, ants, and moths but certain bees and all wasps are principal pollinators, while moths are minor pollinators. Certain other bees and ants act as mere nectar robbers but they appear to compel pollinators to make multiple visits to the flowers thus promoting the pollination rate. The pollinator bees collect only nectar and effect nototribic pollination, which facilitates pollen deposition precisely on their back for effective transfer to other flowers and precludes access to pollen for insect grooming by their legs. Fruit set occurs both in self- and cross-pollination but a significant percentage of fruit abortion occurs in self-pollinated flowers, indicating an inherent regulatory mechanism, which terminates the genetically inferior fruits. Fruits with pulpy exocarp, corky mesocarp and stone-hard endocarp are buoyant and hydrochorous. Seeds germinate and produce new plants on sandy beaches. The plant also propagates by vegetative means through rooting from aerial stems that touch the ground, and also by stem cuttings. The plant is important for sand erosion control, beach stabilization and landscaping through plantation activity. Therefore, it is a promising species for the restoration of coastal vegetation.
