Responses of four Brassica species to sodium chloride

Responses in sand culture of four Brassica species, B. campestris, B. carinata, B. juncea and B. napus to NaCl were assessed for growth and yield. B. napus produced significantly greater fresh and dry biomass than the other three species in NaCl treatments and also a higher seed yield in both absolute and relative terms when grown at 125 mol/m³ NaCl. In contrast, B. campestris had the lowest biomass production, seed yield and oil content. B. campestris did not differ significantly from B. juncea and B. carinata in biomass production for growth, but B. carinata had a significantly higher seed yield (1.60 g/plant) than that of B. juncea and B. campestris (0.69 and 0.61 g/plant, respectively). The higher seed yielding species, B. napus (1.74 g/plant) and B. carinata (1.60 g/plant) accumulated lower amounts of Na⁺ and Cl^? in their tissues and had significantly higher K selectivity (S_K,Na) in their shoots than did those of B. campestris and B. juncea, B. napus and B. carinata also had higher leaf succulence than that of B. campestris. In view of the results presented here it can be concluded that B. napus and B. carinata are relatively tolerant to NaCl whereas B. campestris and B. juncea are relatively sensitive to NaCl.