On the reproductive ecology of Suaeda maritima, S. monoica and S. nudiflora (Chenopodiaceae)

Abstract

Floral biology, sexual system, breeding system, pollinators, fruiting and seed dispersal aspects of three Suaeda species, S. maritima, S. monoica and S. nudiflora (Chenopodiaceae) were studied. The flowers of all the three species are hermaphroditic, dichogamous, strongly protogynous with a pistillage phase during the mature bud stage and staminate phase following anthesis, self-compatible exhibiting mixed breeding systems with special adaptation for cross-pollination; but both self- and cross-pollination are vector-dependent. In all, the flowers display a mix of anemophilous and entomophilous traits. Anemophily is effective in high salt marshes while water currents bring about pollination in low salt marshes; insects pollinate the flowers while collecting the forage from pistillate and staminate phase flowers. In these species, the whole plant breaks off and rolls on the floor while shedding its diaspores. Fruits with seeds intact and/or seeds shed from fruits float on water due to their ability for buoyancy. The fruits and seeds thus disperse, settle in the entire extent of salt marshes or coastal areas and germinate in mid-summer season when salinity is very high in high and low salt marshes.