THE INFLUENCE OF SELENIUM, SALINITY, AND BORON ON SELENIUM UPTAKE IN WILD MUSTARD

Wild brown mustard (Brassica juncea) was shown in greenhouse water cultures to determine the effects of selenium (Se), salinity (salt), and boron (B) in the root media on total Se concentrations in plant tissues. The experimental design was a three-way incomplete factorial with treatments consisting of four Se concentrations (0, 2, 6, and 15 mg Se L-1 as Na2SeO4), four B concentrations (0.1, 2, 6, and 15 mg B L-1 as boric acid) and four salt treatments (0.5, 3, 10, and 15 dS m-1 as NaCl and CaCl in approximately 5:1 ratio by weight). After 40 d of growing in the respective water culture treatment, plants were harvested, separated into shoots and roots and analyzed for total tissue Se and B, and shoot sulfate (SO4) concentrations. The treatments significantly influenced yield and uptake of Se, B, and SO4 by wild mustard. Shoot and root dry weight yields were reduced by 30% and 21%, respectively. Selenium and SO4 tissue concentrations were positively related to solution Se, while the Se model was independent of solution B and salinity. Similarly, B concentrations were positively related to solution B, while the B model was independent of solution Se and salinity. Therefore mustard is reasonably salt tolerant and accumulates Se and B when grown in waters laden with Se and B. © 1990 Kluwer Academic Publishers.