Water stress effects on the seedling growth of Prosopis argentina and Prosopis alpataco

摘要: Abstract The expansion of the Prosopis genus from Chaco region towards drier and colder areas would involve several morphological physiological adaptations that allow these species to occupy different ecological niches. argentina alpataco (Fabaceae, Mimosoideae) are good examples shrubs adapted highly stressed environments. P. reaches its optimum in sandy soils while attains it clayish, saline periodically flooded soils. We analysed effects water stress on early seedling growth alpataco; addition we discussed importance success species. used a completely randomized experimental design with two fixed factors: (P. alpataco), levels supply (350 1400 mm). Water produced detrimental effect both species, which was evident reduction leaf area, height, above-ground root biomass. However, plant more strongly affected by than argentina, as suggested significant species-irrigation interactions ( P 0.05 ) found height biomass variables. proportional (biomass reach relation control treatment) lower (0.14) (0.32). These results indicate has greater tolerance deficit during establishment. Our results, features each consistent previous findings have described xerophyte able cope harsh sand-dune conditions, phreatophytic mesomorphic features.