Micronutrients and Nutrition Security

Definitions

Food security

All people at all times have access at an affordable price to the basic food they need to meet their energy requirements.

 

Nutrition security

Nutrition security means that every individual has access to a balanced diet that includes all essential nutrients (e.g. proteins/amino acids, vitamins, nutritive trace elements). Nutrition security cannot be achieved without first having food security.

 

Micronutrient malnutrition

Diets deficient in micronutrients are characterized by high intakes of staple food crops (such as maize, wheat and rice), but low consumption of foods rich in bioavailable micronutrients such as fruits, vegetables, and animal and fish products.

Micronutrient deficiencies can impair cognitive development, lower resistance to disease in children and adults, and increases risks for both mothers and infants during childbirth. The costs of these deficiencies in terms of lives lost and reduced quality of life are staggering.

 

Micronutrients

18 elements have been shown to be essential for higher plants: carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), sulphur (S), magnesium (Mg), calcium (Ca), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), molybdenum (Mo), chlorine (Cl), nickel (Ni) and cobalt (Co).

These essential elements can be divided into:
• Primary macronutrients (N, P, K) • Secondary macronutrients (S, Mg, Ca) • Micronutrients

The main micronutrients are:
• Iron • Manganese • Zinc • Copper • Boron • Mobybdenum • Chlorine • Nickel • Cobalt

While macronutrients are found in plants at levels of 0.2 to 5.0 % or greater, plant concentrations of micronutrients range from 0.1 to 100 μg/kg.

Other micronutrients are also essential to animal and human health such as iodine (I) and selenium (Se).

     
  ♦ AGRONOMIC FORTIFICATION  
     
  Options available for the fertilizer industry for supplying micronutrients  
 

There are several ways to supply micronutrients to crops: soil application, fertigation, foliar spray, seed treatment, or combination with crop protection products. Each option has specific advantages and disadvantages depending on the nutrient, the crop and the soil characteristics. Similarly, the different product types (e.g. chelated/non-chelated, organic/inorganic, granular/fluid) have respective relative strengths. The various options have quite different impacts on the solubility and availability of the micronutrients, on the uniformity of application, as well as on health, safety and the environment.

The most commonly-used methods are the following:

• Dry mixing is a simple method that works well with non-granular materials. However, there are often caking problems.
The most commonly-used methods are the following:
• Dry mixing is a simple method that works well with non-granular materials. However, there are often caking problems.
• Bulk blending is a form of dry mixing, but with granular material. The main problem is segregation of the different components, unless all the materials have similar particle sizes. Segregation generally leads to uneven application.
• Complex fertilizers: This option might lead to reactions that will affect the solubility of the nutrients.Moreover, unless a micronutrient deficiency is widespread, it is often uneconomical to produce small lots of special grades.
• Coated fertilizers: Micronutrients may be added as coating to straight or complex fertilizers or to bulk blends. This is a quite simple and inexpensive solution. However, it lowers the macronutrient grade. This is an obstacle in countries where only prescribed,registered grades can be marketed.
• Fluid fertilizers: Micronutrients are generally applied in combination with crop protection sprays or with foliar application of macronutrients. They are generally available as prepared mixtures to prevent reactions that create water-insoluble compounds. Their use is limited in developing countries.

  
     

Agronomic biofortification

Increasing the density and balance of essential nutrient in harvested crop products, mainly by means of appropriate management of plant nutrition and crop cultural practices.

 

Genetic biofortification

Increasing the essential nutrient content of crops mainly by breeding plant varieties with greater efficiency of nutrient uptake from soils, enhanced nutrient translocation to edible parts or greater nutrient bioavailability. It is important to note that naturally high-efficiency varieties will remove more nutrients from soils which must therefore be replaced by judicious fertilizer use to avoid nutrient mining and depletion. As a consequence, agronomic and genetic biofortification strategies are inextricably linked in meeting future ‘nutrition security’ goals.

 

Farming for Health

'Farming for Health' describes the utilization of agricultural farms, farm animals, plants and landscapes as a base for promoting human mental and physical health and social well-being.The concept has been developed to meet nutrition security goals.It originates from Wageningen University in the Netherlands and is now represented by an international community of practice of researchers. To learn more about the initiative, Farming for Health .