Revision: Crop Production and Management Science SSLC (English Medium) Class 8 Tamil Nadu Board of Secondary Education

Nitrogen (N), Phosphorous (P), and Potassium (K) are the three important nutrients among the various nutrients needed for plant growth. These three are called Principal Nutrients.

‘Biofertilizer’ contains living micro-organisms which, when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Thus, biofertilizers are organisms that enrich the nutrient quality of the soil.

“Food security exists when all people, at all times, have physical, social and economic access of sufficient, safe and nutritious food which meets their dietary needs and food preferences for an active and healthy life” FAO – 2009.

According to eminent agricultural scientist M.S.Swaminathan, Nutrition security is, “Physical, Economic and social access to a balanced diet, safe drinking water, environmental hygiene, primary health care, and primary education.

A facility where seeds are stored under controlled conditions to preserve plant genetic diversity for future use is called a seed bank.