Muerte por reproducción sexual: El caso (sin resolver) de la floración de los bambúes

Abstract

Bamboos belong to the grass family (or Poaceae). There are 1698 bamboo species distributed around the world in tropical, subtropical and temperate jungles and forests. In our country, there are five native genera that comprise 23 species. The least known characteristic of the woody bamboos is their flowering phenology. Four main types of flowering patterns have been described. However, the most interesting are those bamboo species that show a massive and cyclical flowering pattern, after a long period of vegetative growth. Such mass flowering events occur at roughly regular intervals and are followed by the death of the flowering individuals. The goal of this review is to provide an informative sample of the current knowledge of bamboo flowering, with an emphasis on the species native to Argentina. Currently, the approximate duration of the life cycle of most woody bamboo species in our country is known, based on a review of the collections of the most important national and international herbaria and an extensive bibliographic search. In most species, the average life cycles are multiples of 15-16years, with a 30-year cycle being the most common. The main hypotheses about the evolutionary forces that led bamboos to flower, seed and die synchronously are described. Likewise, environmental, genetic factors and the combination of both proposed as possible ‘causes’ of this atypical flowering pattern of bamboos are discussed. Finally, environmental and social consequences of this phenomenon are listed.