Pollination and mating systems of Apodanthaceae and the distribution of reproductive traits in parasitic angiosperms

Abstract

Sister group comparisons so far do not reveal any reproductive traits that evolved (or were lost) concomitant with a parasitic life style, but the lack of wind pollination suggests that this pollen vector may be maladaptive in parasites, perhaps because of host foliage or flowers borne close to the ground.

Genetic Diversity and Structure in the Philippine Rafflesia lagascae Complex (Rafflesiaceae) inform its Taxonomic Delimitation and Conservation

“…Previously, however, Rafflesia was hypothesized to be dioecious (e.g. Olah 1960;Beaman et al 1988;Renner and Feil 1993;Bellot and Renner 2013;Wicaksono et al 2016; but see Nais 2001 for more cautious statements). This reproductive strategy was considered more likely because Rafflesia species are rare and populations are far apart.…”

“…A geitonogamous breeding system might benefit small Rafflesia populations, because it increases the number of available mates, however, it carries with it the potentially negative consequences of inbreeding (Byers and Meagher 1992;Ellstrand and Elam 1993). Some studies have suggested that dioecy is overrepresented in parasitic plants (Renner and Ricklefs 1995;Bellot and Renner 2013), but this hypothesis rests in part on the assumption that the presence of pistillate and staminate flowers of endophytic parasites on the same host belong to different parasite individuals (Bellot and Renner 2013). If endophytic parasites with unisexual flowers such as those in Apodanthaceae and Rafflesiaceae are indeed monoecious, then the incidence of dioecy among all parasites has been overestimated.…”

The systematics of the worldwide endoparasite family Apodanthaceae (Cucurbitales), with a key, a map, and color photos of most species

“…Flowers unisexual, plants dioecious or monoecious, a point still insufficiently known; flowers of both sexes on the same host or not. Pollination by flies and bees, possibly also wasps (Bellot and Renner 2013; Sipes et al 2014), based on the fruit color and size, dispersal is probably by birds. Flowers white or yellow ( Apodanthes ), or white, pink, orange, red, purple or brown ( Pilostyles ), aggregated on the host stems, minute (1.5 to 15 mm long when dried), usually with radial symmetry.…”

Ecological aspects of Langsdorffia hypogaea (Balanophoraceae) parasitism in the Pantanal wetlands

“…Bellot & Renner (2013), who conducted a study on the pollination and reproductive traits of parasitic angiosperms, reported that most of the families that support parasites are pollinated predominantly by insects and by some vertebrates, and that they are dispersed mainly by birds and mammals. However, we are still far from understanding the ecological and evolutionary interactions among hosts, parasites, their pollinators and dispersers, even of the most extensively studied species, because ecological data have been slow to accumulate.…”