Tropical Ecology and Conservation [Monteverde Institute]

Alternative Title

Efectos de la elevación en la eliminación de polinarias en Asclepias curassavica (Asclepiadaceae)



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Publication Date

November 2000


Pollinaria removal was studied in three populations of Asclepias curassavica located on an elevational gradient in and around Monteverde, Costa Rica (815m, 1175m, 1440m). The following plant characteristics were also studied: number of inflorescences, number of flowers per inflorescence, number of pollinaria removed per flower, number of pods. Pollinaria removal in plants with the presence of herbivory was compared to pollinaria removal in plants without herbivory at all three elevations. Pollinaria removal and the presence of aphids were compared the same way as herbivory. Data were collected over a nine day period during the misty season (October – November). Results showed a significant difference in pollinaria removal between all three elevations (ANOVA P- value < 0.0001). Pollinaria removal was lowest at the low elevation site, intermediate at the middle elevation site and highest at the high elevation site. These results may be explained by an increase in pollinators, specifically the Monarch butterfly (Danaus plexippus), as elevation increases, or the density of the plants per site. The highest numbers of pods per plant were observed at the high elevation site, which may indicate those plants also have the highest fitness. Significant differences in number of pods per plant were seen between high and low, and low and middle elevations (ANOVA P- value < 0.0001; Fisher’s PLSD both P-values < 0.0001). Neither the presence of herbivory nor presence of aphids had a significant effect on pollinaria removal. The number of flowers per inflorescence was highest at the high elevation site and lowest at the low elevation significantly affects pollinaria removal in Asclepias curassavica. En este proyecto se estudio la remoción de polen en tres grupos de plantas Asclepias curassavica (Asclepiadaceae) a diferentes elevaciones (815m, 1175m, 1440m). Además se tomo: número de floraciones, número de flores por floración, número de polen removido por flor, número de frutos, presencia de herbívoros, y presencia de pulgones. Los datos se colectaron por nueve días durante Octubre y Noviembre del 2000. Los resultados indican una diferencia significativa entre todas las elevaciones con respecto a número de polen removido por flor (ANOVA P-value < 0.0001; Fisher’s PLSD alta y intermedia, intermedia y baja, alta y baja, todos P-values < 0.0001). La remoción de polen fue mas baja en la elevación baja, intermedia en la elevación intermedia y más alta en la elevación alta. Los resultados se pueden explicar por una presencia mayor de polinizadores en la elevación alta, específicamente la Monarca (Danaus plexippus). La elevación alta tuvo el mayor número de frutas por planta y más número de plantas con presencia de herbívoros. La elevación intermedia tuvo el mayor número de plantas con presencia de pulgones. El número de flores por planta fue mayor en la elevación intermedia y menor en la elevación alta. De cualquier modo, la elevación alta tuvo el mayor número de las flores por floración. La elevación es un factor importante que afecta la remoción de polen en las flores de A. curassavica.


Plants, Effect of altitude on, Plantas, Efecto de la altitud en, Pollination, Polinizacion, Costa Rica--Puntarenas--Monteverde Zone, Costa Rica--Puntarenas--Zona de Monteverde, CIEE Fall 2000, CIEE Otoño 2000


Student affiliation : Department of Biology, Rhodes College, Memphis, Tennessee Digitized by MVI

Subject: topical

Plants; Effect of altitude on; Plantas; Efecto de la altitud en; Pollination; Polinizacion; CIEE Fall 2000; CIEE Otoño 2000

Subject: geographic

Costa Rica--Puntarenas--Monteverde Zone; Costa Rica--Puntarenas--Zona de Monteverde



Holding Location

Monteverde Institute MVI



Effects of elevation on pollinaria removal in Asclepias curassavica (Asclepiadaceae)



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