Quantifying and understanding reproductive allocation schedules in plants

Abstract

A plant's reproductive allocation (RA) schedule describes the fraction of surplus energy allocated to reproduction as it increases in size. While theorists use RA schedules as the connection between life history and energy allocation, little is known about RA schedules in real vegetation. Here we review what is known about RA schedules for perennial plants using studies either directly quantifying RA or that collected data from which the shape of an RA schedule can be inferred. We also briefly review theoretical models describing factors by which variation in RA may arise. We identified 34 studies from which aspects of an RA schedule could be inferred. Within those, RA schedules varied considerably across species: some species abruptly shift all resources from growth to reproduction; most others gradually shift resources into reproduction, but under a variety of graded schedules. Available data indicate the maximum fraction of energy allocated to production ranges from 0.1 to 1 and that shorter lived species tend to have higher initial RA and increase their RA more quickly than do longer‐lived species. Overall, our findings indicate, little data exist about RA schedules in perennial plants. Available data suggest a wide range of schedules across species. Collection of more data on RA schedules would enable a tighter integration between observation and a variety of models predicting optimal energy allocation, plant growth rates, and biogeochemical cycles.

Climatic warming strengthens a positive feedback between alpine shrubs and fire

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Dioecious plants are more precocious than cosexual plants: A comparative study of relative sizes at the onset of sexual reproduction in woody species

“…The size at which an organism begins to reproduce has a large influence on population growth rates (Gadgil & Bossert, 1970) and the fitness of individuals (Wenk & Falster, 2015). The precocity of dioecious plants should alleviate their reproductive disadvantages at the population level.…”

Post-fire resprout in an endangered and narrow endemic shrub from rupestrian grasslands, Serra do Cipó, southeastern Brazil

“…Entre as principais ameaças à sobrevivência dessa espécie está o aumento do turismo desordenado propiciado pela pavimentação da rodovia MG-010 que corta a região, além das constantes queimadas associadas à presença de gramíneas africanas invasoras provenientes de fazendas de criação de gado (Viana et al, 2005;Barbosa et al, 2010;Guimarães et al, 2014).…”