Abstract
The life table of a population of Mesembryanthemum nodiflorum growing at the Egyptian Deltaic Mediterranean coast was analysed. Results indicated that the population tended towards a Deevey-type I survivorship curve with population collapse following peak reproduction, a behaviour characteristic of an r-selected species. Growth of the population extended into early summer the period of low soil water content that did not seem to be favourable to other annuals growing at the study site. Physiological studies indicated that M. nodiflorum exhibited diurnal acid fluctuations. Both leaf relative turgidity and leaf succulence rapidly responded to irrigation by attaining values higher than those of non-irrigated control plants, and a significant reduction of both nocturnal acidification and leaf proline content were observed. It is concluded that facultative induction of Crassulacean Acid Metabolism (CAM) in M. nodiflorum permits persistence of the plant late into growing season.