Nutrient Science

All growing plants need the proper amounts of 17 essential elements to develop and grow to their full genetic potential. Of these 17, 14 are usually absorbed by the plant from the soil through its roots. The three remaining elements, carbon, hydrogen and oxygen come from the air.

The micronutrients requirements by plants for normal growth and high yield are small compared to those of the macronutrients so traditionally, emphasis in crop nutrition has been on nitrogen (N), phosphorous (P) and potassium (K). Despite the small amounts of micronutrients needed by plants to complete their life cycles, deficiencies of one or more of these elements frequently occurs in agriculture, horticulture and forestry around the world.

The table below are the essential micronutrients required for higher plants and the relative amounts of each required for healthy plant growth.

Impact of micronutrient deficiency

Historically the impact of micronutrient deficiencies on crop production has been most commonly measured as loss of crop yield. A variety of other properties may be more important than yield alone. For range crops, aspects of crop quality such as oil, protein or fiber content, are important for the price of agriculture markets. For forest products, tree form and wood quality are as important as wood volume in determining the economic value of the harvest (Dell et al., 2003).

In a cropping system, the main impact of micronutrients may be on amounts of nitrogen fived by legumes. Another aspect of impact is the effect of micronutrient concentrations in planting seed on the vigor of the next season’s crop. An emerging area of interest is the impact of micronutrient supply on grain quality for human and animal nutrition.

Agriculture can help address malnutrition around the world:

Malnutrition, often called the “hidden hunger”, can lead on to life-threatening illnesses caused by a lack of protein (protein-energy malnutrition) or micronutrients. Micronutrient deficiency is attributed to malnutrition which weakens immune systems, exacerbates the effect of childhood diseases such as measles, malaria, pneumonia and diarrhea, and can permanently impair long-term physical and cognitive development.

Micronutrient-enriched fertilizers improve soil fertility, helping to support higher yields of more nutritious food. Poor soil quality is a significant factor that leads to micronutrient deficiencies in humans – if the soil is not rich in all the necessary nutrients, food products will not contain the necessary nutritional balance. A program in Turkey has used a technique to restore micronutrients in the soil to successfully address zinc deficiencies in their population.

“Faster progress must be made in the drive for adequate food, good nutrition, good health, and sustainable agricultural growth, but the three sectors (farming, nutrition, and health) must work together to minimize the negative links among them and maximize the positive synergies.” (Leveraging Agriculture for Improving Nutrition and Health: The Way Forward, IFPRI, February 2011)