Response of seven African eggplant (Solanum macrocarpon L.) cultivars produced in Benin to salinity stress at seedling stage

Salt stress is one of the abiotic factors that cause a depressive effect on plants. This work aims to evaluate the effect of salt stress on growth of young plants of 7 cultivars (Adja-ouere, Côte d’Ivoire, Dangbo, Kpinman, Kombara F1, Lanman and Togan) of African eggplant (Solanum macrocarpon) produced in Benin, locally called Gboma, in order to determine their relative salt-resistance levels. Five NaCl concentrations (0; 30; 60; 90 and 120 mM) were applied to 4-weeks old plants for 2 weeks in a completely randomized design with 3 replicates. Results revealed that the 3 root growth parameters evaluated were only significantly affected for one of the 7 cultivars while for the growth parameters of the aerial part, at least 4 cultivars were significantly affected except for leaf number. Thus, growth of aerial part was more sensitive to salt stress than that of root part. Cultivar Dangbo, which did not undergo significant reduction in growth for none of the 9 parameters evaluated, was the most salt resistant. It was followed by Togan which underwent significant growth reduction for only 3 growth parameters and only at the highest NaCl concentrations used. On the other hand, cultivar Kombara F1 which underwent a significant growth reduction from the lowest NaCl concentrations used for 4 of the nine parameters evaluated was the most salt sensitive. It was followed by Lanman, Kpinman and Adja-ouere with respectively 3, 2 and 2 growth parameters significantly reduced at the lowest NaCl concentrations used. Cultivar Côte d’Ivoire showed intermediate behavior.