Selective mortality on haploid and diploid microscopic stages of Lessonia nigrescens Bory (Phaeophyta, Laminariales)

摘要: Abstract In seaweeds, potential selective events on juveniles are particularly important because the highest mortality rates usually affect these microscopic stages rather than macroscopic ones. This study evaluates degree to which induced by herbivory and wave impact size (mean whole distribution) of haploid, gametophytic, diploid, early sporophytic intertidal kelp Lessonia nigrescens . theory, in species with a complex life history, effect haploid diploid individuals may range between two extremes. One inhibition, where same feature, conferring higher survival one phase, cause opposite following phase. The other extreme is synergism, selection operates similarly among alternating history phases. Controlled experiments showed that herbivorous snails had more significant negative gametophytes slightly larger, sporophytes. Conversely, separate eliminated efficiently larger plantules smaller Size selectivity both agents occurred only stages, when plantule sizes were longer 20 μm. Directionality indicated individuals, developed adhesive rhizoids, rates. directional plants neither reinforced, or cancelled out, alternate stages. Thus, no inhibitory synergetic effects observed for These results suggest that, compared organisms direct cycles, those having histories, independent phases, have at least restriction occurrence evolutionary change. Namely, equivalent expression response involved traits phases putative agents.