Evaluating the Effect of Salt Stress Conditions on the Growth, Yield and Nutrient Composition of Calyces and Leaves of Roselle (Hibiscus sabdariffa L.) Cultivars in Far North Region of Cameroon

Context: In sahelian and coastal areas, salinity is a permanent treat to the growth and devolpment of plants. The choice of salt-tolerant species would be a solution to this constraint. Objective: The purpose of this work was to study the effect of the different NaCl concentrations on the growth, the yield and the nutritional composition of leaves and the calyx in two cultivars of Roselle (Hibiscus sabdariffa L.) i.e: green bissap and red star. Methodology: The plants were subjected to different doses of NaCl ranging from 0, 60, 120 to 240 mM for 60 days in a completely random blocking design having four block. Results: Increase in NaCl levels had no appreciable effect on growth, yield and chemical composition of leave and calyce of roselle. Application of NaCl (from 0 to 240 mM) led to a decrease of leaf yield (27.5% and 24.7% in Red star and Green bissap respectively), calyce yield (23.1% and 31.6% in Red star and Green bissap respectively), seed yield (29.8% and 32.8% in Red star and and Green bissap respectively) and accumulation of osmolytes, fiber content, Na content of leave and calyce and total anthocyanin content of calyce (25% and 66.5% in Red star and Green bissap respectively). The Na+ content obtained in the aerial parts (leave and calyce) was very low in the Red star cultivar and high in Green bissap. Conclusion: The Red star (red bissap) cultivar is more salt tolerant than the Green bissap and therefore suggests that it could be a promising crop for farmers in salinity-prone areas and the coastal belts in tropical and sub-tropical regions.