Essentiality of Micronutrients in Soil: A Review

Micronutrients are very abundant in soil but plants normally absorb only a little amount of them, giving them the name "trace elements". Boron (B), Copper (Cu), Iron (Fe), Manganese (Mn), Zinc (Zn), Molybdenum (Mo), and Nickel (Ni) are the essential micronutrients that are required in smaller amounts but crucial for plant growth and development. Besides providing essentiality in fruits and seeds formation, they are helpful in performing various metabolic processes, nutritional management, reproductive growth, chlorophyll synthesis, and other key plant activities. Among all the essential micronutrients, two particular elements, zinc (Zn) and boron (B) are deficit in acidic soils and zinc (Zn) and iron (Fe)are insufficient in semi-arid soils, which have become a rising problem in a variety of cropping systems thereby, raising alarms for the future. Our understanding of difficulties relating to micronutrients might be improved by the production of detailed soil micronutrient maps that cover wide geographic regions, making relevant judgments about the delivery and distribution of fertilizers supplemented with micronutrients to areas that are deficient in these particular micronutrients. The outcomes of these delineation efforts would also be very helpful in developing site-specific suggestions to increase the micronutrient content of food crops. It's important to note that soil micronutrient availability directly affects plant growth.