“…Hydrogen sulfide, formed under submerged anaerobic conditions, induces iron toxicity, which prevails in rice-growing areas (Tanaka and Yoshida 1970). Nevertheless, sulfur deficiency in rice plants was observed in several countries; e.g., Bangladesh (Karim and Majlis 1958), Brazil (Wang 1979), India (Saran 1949), Indonesia (Ismunadji et al 1975), Myanmar (Aiyar 1945), and the Philippines (Lockard et al 1972). The deficiency is due mostly to a dilution effect caused by increasing yields associated with the intensive use of high-analysis fertilizers that contain little or no sulfur, and the exploitation of new lands in marginal areas.…”