The Roles of Plant Secondary Chemicals in Wet Tropical Ecosystems

Regeneration Ecology of Eperua grandiflora (Caesalpiniaceae), a Large-Seeded Tree in French Guiana

“…One may regard E. grandiflora's large seed and resprouting ability as an adaptation to compensate for very low dispersal by rodents and intense seed predation and seedling damages, and perhaps an alternative to a high investment in chemical and physical defenses (see e.g., Coley 1983Coley , 1988Langenheim 1984;Coley & Aide 1989), as seems to be the case in E. falcata. Nonetheless, E. grandiflora seeds and seedlings survive stem trauma and young leaf defoliation relatively well because large amounts of nutrient reserves provide energy to produce new photosynthetic tissue.…”

“…Based on Janzen's (1970) and Connell's (1971) hypotheses united in the Escape Hypothesis of Howe and Smallwood (1982) and the Janzen-Connell Model of Clark and Clark (1984), one can postulate three patterns of recruitment for this species. The ability of E. grandiflora to persist in the understory would then result from balances between seed fitness for dispersal (Schupp et al 1989) correlated with seed size (Foster & Janson 1985) and seedling vigor (Foster 1986), and between nutrient reserves and the damage pressure that would be correlated with chemical and morphological protection and growth rate (Coley 1983(Coley , 1988Langenheim 1984, Foster 1986). The first type would be a null pattern because where neither secondary dispersal nor predation occurs, one can expect dense juvenile clumps to grow essentially below adults.…”

Tropical Rainforest Gaps and Tree Species Diversity

“…Leaves high in N, protein, and water, and low in fiber, phenols, and toughness experience higher rates of herbivory than do tougher, low quality leaves (51,52,113). Young leaves suffer more herbivore damage than do mature leaves, and the short-lived leaves of high-light species are eaten more than are the tougher, long-lived leaves of shade-tolerant species (52, except see 125).…”

Red coloration of tropical young leaves: a possible antifungal defence?

“…The fungus is the sole food source for larvae and composes much of the diet for the workers and queen (Kermarrec et al 1986, Quinlan & Cherrett 1979). Because of this dependence on the fungus, the ants have apparently been selected to avoid cutting leaves with anti-fungal compounds (Howard 1987, Howard & Wiemer 1986, 1984.…”