Composition of Extrafloral Nectar Influences Interactions between the Myrmecophyte Humboldtia brunonis and its Ant Associates

摘要: Ant-plant interactions often are mediated by extrafloral nectar (EFN) composition that may influence plant visitation ants. Over a 300 km range in the Indian Western Ghats, we investigated correlation between EFN of myrmecophytic ant-plant Humboldtia brunonis (Fabaceae) and number species ants visiting EFN. varied among H. populations organs (floral bud vs. young leaf EFN). In general, was rich sugars with small quantities amino acids, especially essential had moderate invertase activity. experiments at study sites sugar acid solutions or floral mimics, dominant EFN-feeding differentiated as well mimics. The castration parasite Crematogaster dohrni (northern site) least selective did not exhibit any clear feeding preferences, while largely trophobiont-tending non-protective Myrmicaria brunnea (middle preferred higher sucrose concentrations certain essential/non-essential mixtures. mutualistic Technomyrmex albipes (southern over glucose fructose consumed mimic to greater extent than mimic. This low concentrations, lowest viscosity sugar:amino ratio, appeared ideally suited digestive physiology T. albipes. preference for explain protection afforded leaves buds albipes, also help resolve ant-pollinator conflicts. differential response sugar, solution suggests plants can fine-tune their local via composition. Thus, mediate partner-choice mechanisms interactions.