Effect of salt stress on flowering, fructification and fruit nutrients concentration in a local cultivar of chili pepper (Capsicum frutescens L.)

Salt stress is one of the major environmental constraints limiting agricultural productivity and influencing the concentration of bioactive compounds of vegetables. In this study, we assessed the effect of NaCl salt stress on flowering, fructification and fruit nutritional quality of a local cultivar of chili pepper. The experiment was carried out in a screen house as a completely randomized design (CRD) with three replications. Three weeks old plants were submitted in pots containing a mixture of potting soil and sand, to five NaCl concentrations; 0, 30, 60, 90 and 120 mM NaCl by irrigation every two days for 94 days. Salinity retarded significantly flowering and fruit ripening, and reduced significantly the fruit number, as the NaCl concentration increased with no fruit obtained at 90 and 120 mM NaCl. Fruit size and fresh mass were also significantly reduced by salt stress. Capsaicinoids contents increased significantly for about 389% in comparison to the control at 60 mM NaCl, whereas vitamins B6, B12 and C contents decreased significantly with increasing NaCl concentration. Thus, salt stress retarded flowering and fruit ripening; reduced fruit number, size and mass; enhanced fruit tangy appearance and deteriorated fruit nutritional values in chili pepper.   Key words: chili pepper, local cultivar, NaCl, capsaicinoids contents, vitamins contents, fruits growth, Benin.