A test of the pollinator limitation hypothesis for a neotropical herb

Hand pollination of Calathea ovandensis (Marantaceae) increased the number of initiated fruits by 24%, number of mature fruits by 6.8%, and number of seeds by 12.6%, but only the first of these differences was statistically significant. The proportion of flowers that matured fruits was very low compared with data reported for other species: 8.1% for hand-pollinated treatment, 7.4% for open-pollinated controls. The proportion of flowers that initiated fruits was also quite low: 24.5% for hand-pollinated plants, 20.2% for open-pollinated plants. Antguards attracted to extrafloral nectaries on the inflorescence appeared to stimulate flower production, while an ant-tended herbivore of reproductive tissues had a negative effect on fruit maturation. While fruit initiation was pollen-limited, mature fruit and seed production were limited primarily by resources. -from Authors