干旱区生态环境知识资源中心

Saline stress on Jatropha curcas, a plant native to humid tropical areas, was assessed to determine its potential for cultivating it as a biodiesel crop in arid and saline areas and compared with Jatropha cinerea, a wild species of saline dry areas. J. curcas and J. cinerea were subjected to four NaCl concentrations (0, 50, 100 and 200mM) for 28 days, and the effects on growth, ion relations, water potential and stomatal conductance were measured. Both species had the capacity to regulate and maintain water uptake. Stomatal conductance decreased in approximately the same amount in both species. Chlorophyll content decreased only in J. curcas. Biomass production was strongly affected in both species, probably as a consequence of reduced stomatal conductance and ion toxicity. Biomass production and ion relations responded similarly at 50mM, but salinity inhibited J. curcas more than J. cinerea at 100mM from larger Na+ uptake and nutritional disorder. Young J. curcas plants have the capacity to grow in dry areas when soils are moderately saline.