Stamen movements in flowers ofOpuntia (Cactaceae) favour oligolectic pollinators

Plants on the move: Towards common mechanisms governing mechanically-induced plant movements

“…68 Mechanically stimulated stamen movements were also seen in the genera Opuntia (Cactaceae). 69 These flowers have many whorls of stamens that are longer on the outer whorls and shorter in the inner ones. 69 When a visiting bee mechanically stimulates the stamen filaments, they instantly bend toward the style (i.e., the center of the flower) and the longer filaments covers the shorter ones, hindering the access of pollen foragers to the source of nectar.…”

“…69 These flowers have many whorls of stamens that are longer on the outer whorls and shorter in the inner ones. 69 When a visiting bee mechanically stimulates the stamen filaments, they instantly bend toward the style (i.e., the center of the flower) and the longer filaments covers the shorter ones, hindering the access of pollen foragers to the source of nectar. 69 Interestingly, the bees that effectively pollinate these flowers are the ones capable of crawling down the space between the innermost stamen and the style, having access to the majority of pollen and nectar resources.…”

“…69 Interestingly, the bees that effectively pollinate these flowers are the ones capable of crawling down the space between the innermost stamen and the style, having access to the majority of pollen and nectar resources. 69 Orchids are known to have developed outstandingly specialized structures in order to increase reproductive success and it is not surprising that some genera belonging to this family present examples of moving floral parts. The orchid genus Catasetum, for example, has sexually dimorphic flowers with significantly differences between male and female flowers, which are pollinated exclusively by male euglossine bees that collect chemical attractants.…”

“…69 When a visiting bee mechanically stimulates the stamen filaments, they instantly bend toward the style (i.e., the center of the flower) and the longer filaments covers the shorter ones, hindering the access of pollen foragers to the source of nectar. 69 Interestingly, the bees that effectively pollinate these flowers are the ones capable of crawling down the space between the innermost stamen and the style, having access to the majority of pollen and nectar resources. 69 Orchids are known to have developed outstandingly specialized structures in order to increase reproductive success and it is not surprising that some genera belonging to this family present examples of moving floral parts.…”

Floral movements: Stamen motion in Berberis trifoliolata

“…Ren (2010) suggested that there are four main types of stamen movement: cascade movement (Weigend and Gottschling, 2006); quick and explosive movement (Taylor et al, 2006); simultaneous and slow movement (Azuma et al, 2005); and stimulated movement (Lechowski and Bialczyk, 1992;Lebuhn and Anderson, 1994). Stamen movement can affect the reproductive biology of fl owering plants because this mechanism forces the visitors to enter fl owers and may alter the interaction plant-pollinator (Schlindwein and Wittmann, 1997;Edwards et al, 2005;Liu et al, 2006;Ren, 2010).…”