Plant senescence.

Senescence is defined by evolutionary biologists as the decline in age-specific survival and fecundity that reflects declines in the performance of many different physiological functions in individuals of sufficiently advanced age. Senescence is widely recognized to occur among plants with a single reproductive event, but the extent to which senescence occurs among plants with multiple reproductive events is open to debate. The latter may show gradual or even negligible senescence. The pattern of senescence cannot readily be ascribed to either morphology or phylogeny. While it has been widely argued that clonal growth allows plants to escape senescence, this is not necessarily the case.