Growth and chloride accumulation in soybean cultivars treated with excess KCl in solution culture

Sensitivity to chloride was measured in soybean [Glycine max (L.) Merr.] cu ltivars Rinjani, Lokon, and Merbabu from Indonesia, and Lee from the United States. Plants were grown in solution culture to which KCl (0, 50, or 100 mol m(-3)) was added gradually during days 7-14 after emergence. Excess KCl reduced growth, measured as leaf area, shoot and root biomasses, total bio mass, and root/shoot ratio in 24-day-old plants of all cultivars. The culti var x KCl treatment interaction was significant for all growth parameters. The order of chloride tolerance at 50 mol m(-3) Cl-, based on the mean of a ll growth parameters relative to the control, was Lee>Rinjani>Lokon=Merbabu . In the 50 mol m(-3) Cl- treatment Lee excluded Cl- from the leaves, and a ccumulated Cl- in the roots; Lokon, Rinjani, and Merbabu excluded less Cl- from the leaves. At 100 mol m(-3) KCl, cultivar Lee lost its capacity to ex clude Cl- from the leaves and its growth was poor. Chloride exclusion from the leaves at 100 mol m(-3) KCl was most effective in Lokon, which correspo nded to the relatively good growth of this cultivar in the high KCl treatme nt.