Abstract

There is an extensive body of information available, which is related to boron (B) and molybdenum (Mo) in crops and soils. This entry places major emphasis on the toxicity aspect of these two micronutrients. In nature, mineral toxicities are mainly due to overfertilization and due to the addition of waste materials, such as sewage sludge, mine tailings, and fly ash, containing high amounts of these elements. Toxicity of these elements is reported in regions derived from rocks containing high amounts of these two elements. Certain environmental factors and soil physical properties can cause accumulation of these elements in quantities toxic to crops, livestock, and humans. Data reported in this investigation include information on sources and management of toxicities by methods such as phytoremediation, judicious use of waste materials, use of crop cultivars less sensitive to toxicity, and development of varieties tolerant to excesses of these elements.