Importance of micronutrients in agriculture in Africa and their impacts on health: A review

Abstract

Micronutrients deficiency in African soils is assuming alarming rates and may be responsible for the declining yields and quality of crops. These have serious implications on the attainment of the current global agenda: 2030 Agenda for Sustainable Development Goals (SDGs) to end hunger, achieve food security, improve nutrition and promote sustainable agriculture in Africa. These challenges are attributable to: inherent poor soil fertility, use of high analysis NPK fertilizers containing lower quantities of micronutrients, and the increase in cultivation intensity with high-yielding crop cultivars that remove higher quantities of micronutrients from the soil. Micronutrients malnutrition or “Hidden Hunger” is now a massive and rapidly growing public health problem among nearly all poor people in Africa, leading to unproductive work force. Molybdenum deficiency for instance leads to health challenges such as retarded weight gain, decreased food consumption, impaired reproduction, shortened life expectancy, neurological dysfunction, dislocated ocular lenses, and mental retardation. Related deficiency symptoms of micronutrients in plants (Iron, Manganese, Zinc, Copper, Molybdenum, Boron and Cobalt) and in animals (Arsenic, Iodine, Boron, Chromium, Copper, Fluorine, Iron, Manganese, Molybdenum, Nickel, Selenium, Vanadium, Silicon and Zinc) are fully discussed in this paper. To alleviate micronutrients deficiency, the paper identifies the intensification of agriculture through the incorporation of micronutrients fertilizers in African farming systems, molecular alterations of plant genes to improve micronutrients supplies, increasing translocation, remobilization and deposition of micronutrients, improving the bioavailability of micronutrients in plant food and increasing the accumulation of micronutrients and vitamins in edible parts of food crops through the process of bio-fortification.