WIND POLLINATION, SELF‐INCOMPATIBILITY, AND ALTITUDINAL SHIFTS IN POLLINATION SYSTEMS IN THE HIGH ANDEAN GENUS ESPELETIA (ASTERACEAE)

作者：Paul E. Berry, Ricardo N. Calvo · 发表于：American Journal of Botany · 年份：1989 · DOI：10.1002/j.1537-2197.1989.tb15145.x · 被引用次数：137 · 研究领域：Plant and animal studies、Plant Parasitism and Resistance、Ecology and Vegetation Dynamics Studies

Altitudinal changes in breeding and pollination systems of tropical montane plants were studied in 13 species of Espeletia growing in the Venezuelan Andes from 2,000 to 4,300 m. Hand pollination tests showed that all species were strongly self‐incompatible. The four species found only above 4,000 m had up to 10% median seed set in self‐pollinated heads, which was significantly higher than the lower elevation species. Nine species were insect‐pollinated, with large bees the major pollinator group. An endemic páramo hummingbird, Oxypogon guerinii, was an important visitor of E. schultzii in three populations examined. Experimental bagging experiments showed that the four high elevation species were wind‐pollinated, further evidenced by the lack of pollinator visits and markedly different capitulum morphologies. Open‐pollinated seed set in two wind‐pollinated species, E. spicata and E. timotensis, was strongly dependent on the population's flowering density, which varied significantly from year to year. The shift from insect to wind pollination in Espeletia can be related to the low pollinator availability at high elevations in the Andes, protection of the capitula from snow and daily frosts, and the extremely long flowering periods of individual heads.