ABSTRACT
J. S. McHague established the essentiality of manganese (Mn) for higher plants in 1922. However, most of the research on nutrition of Mn in crop plants was conducted in the second half of the 20th century. There are still many gaps in our understanding of the genetics of mineral nutrition of higher plants. Manganese deficiency as well as toxicity has been reported in different crops and soils around the world (Clark, 1982; Fageria, 2001; Fageria et al., 2002). Approximately one-fourth of the earth’s soils are considered to produce some kind of mineral stress (Dudal, 1976; Baligar et al., 2001). Manganese deficiency has been reported for plants grown in coarse-textured and poorly drained coastal plains soils of the United States (Reuter et al., 1988) and in soils of Central America, Brazil, and Bolivia (Leon et al., 1985; Fageria et al., 2002). Manganese deficiency of rice occurs on high-pH organic soils used for rice production in the Florida Everglades Agriculture Area (Snyder et al., 1990). In Europe, Mn deficiency has been reported for plants grown in peaty (England and Denmark), coarse-textured (Sweden and Denmark), coarse/fine textured (Netherlands), and podzolic and brown forest (Scotland) soils (Welch et al., 1991). Manganese deficiency has also been reported on plants grown in semiarid regions of China, India, southeast and western Australia, Congo, Ivory Coast, Nigeria, and other western African countries (Fageria et al., 2002).
