Fig. 1.

H₂S but not other sulphur- or sodium-containing compounds derived from NaHS contribute to increased chlorophyll content in iron-deficient maize plants. Maize seedlings were pre-treated with different sulphur-containing compounds for 8 d and then grown in a nutrient solution containing 1 µM Fe(III)-EDTA (–Fe) for 12 d. Data are presented as means ± SE. Columns labelled with different letters indicate significant differences at P<0.05.