Temporal, spatial and biotic variations in extrafloral nectar secretion by Macaranga tanarius
Article first published online: 25 DEC 2001
Volume 14, Issue 6, pages 749–757, December 2000
How to Cite
M., H., B., F., B., B. and K. E., L. (2000), Temporal, spatial and biotic variations in extrafloral nectar secretion by Macaranga tanarius. Functional Ecology, 14: 749–757. doi: 10.1046/j.1365-2435.2000.00480.x
- Issue published online: 25 DEC 2001
- Article first published online: 25 DEC 2001
- ant–plant interaction;
- plant–animal interaction
- 1Many plants produce extrafloral nectar (EFN) to nourish ants and other animals which defend them against herbivores. We aimed to find reasons for the high variability in amounts of EFN produced by most plant species. We investigated the influence of several biotic and abiotic factors (time of day, leaf age, nectar removal and leaf damage) on secretion rates of EFN in the common south-east Asian pioneer tree species, Macarangatanarius (L.) Muell. Arg.
- 2In most experiments leaves were washed with pure water and bagged in nets to protect them against nectar-collecting insects, and nectar was collected and quantified 24 h later. Six soluble sugars and up to eight amino acids were detected in nectar samples derived from untreated, field-grown plants. Total amounts of soluble substances varied more than the relative composition of EFN.
- 3Nectar secretion rates were highest on young, expanded leaves. A diurnal pattern with a secretion peak in the first 2 h after dusk was detected in the field. Nectar removal had a positive effect and its accumulation a negative effect on further EFN production. Artificial leaf damage (punching leaves with a needle or removing parts of the leaf blade with scissors) led to a significant induction of EFN production for the next 3 days.
- 4Extrafloral nectar of M. tanarius was secreted in complex patterns influenced by different biotic and abiotic factors; its production appeared to be adapted temporally and spatially in order to ensure optimal use of invested resources.