Flower morphology and its relationship with the pollination system in the southern South American genus Jaborosa (Solanaceae).

IBAÑEZ, ANA CLARA; SÉRSIC, ALICIA NOEMÍ; MORÉ MARCELA

Drakensberg

Congreso; South African Association of Botanists (SAAB), 39th Annual Conference; 2013

South African Association of Botanists

Floral morphology is an important factor in the reproductive isolation of sister species because of its influence on pollinator behaviour, either through pollinator attraction or its functional fit with the pollinator. In this work, , we quantified through traditional and geometric morphometric techniques the interspecific variation in flower morphology of 13 species of the genus Jaborosa Juss. (Solanaceae) to determine whether these variations arised as the result of selective pressures exerted by different groups of pollinators, or as the result of the evolutionary history of the lineage. To elucidate this, flower morphology and pollination mode were mapped onto a phylogeny of the genus and their respective ancestral states were reconstructed. The studied species showed a large variation in flower morphology that ranges from salverform flowers with star-shaped limbs and anthers and stigma included within the tube to rotate flowers with rounded limbs and exserted anthers and stigma. Variations in both, flower architecture, and anthers and stigma location determine that pollen is placed either in the proboscis of hawkmoths (J. integrifolia) and moths (J. caulescens), or in the dorsal (J. rotacea, J. sativa) o ventral (J. laciniata, J. magellanica) body part of the saprophilous flies. These differences in flower morphology were not associated with the evolutionary history of the lineage, suggesting that the shift in pollination mode would be responsible of the diversification of the flower morphology in this genus.