(a) Organic Farming.

Organic farming is an alternative agricultural system which originated early in the 20th century in reaction to rapidly changing farming practices. Organic agriculture continues to be developed by various organic agriculture organizations today. It relies on fertilizers of organic origin such as compost, manure, green manure, and bone meal and places emphasis on techniques such as crop rotation and companion planting. Biological pest control, mixed cropping and the fostering of insect predators are encouraged.

(b) Mixed cropping.

Mixed farming exists in many forms depending on external and internal factors. External factors are weather patterns, market prices, political stability, technological developments, etc. Internal factors relate to local soil characteristics, composition of the family and farmers' ingenuity. Farmers can decide to opt for mixed enterprises when they want to save resources by interchanging them on the farm - because these permit wider crop rotations and thus reduce dependence on chemicals, because they consider mixed systems closer to nature, or because they allow diversification for better risk management.

(c) Intercropping

Intercropping is a multiple cropping practice involving growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop.

(d) Crop rotation.

The growing of different crops in succession on a piece of land to avoid exhausting the soil and to control weeds, pests, and diseases.

(e) Weeds

Weeds are plants that grow near the main crop and take up the nutrients, soil and water of the main crop. They also deprive main plant of nutrition.

(f) Pathogen.

An agent that causes infection or disease, especially a microorganism, such as a bacterium or protozoan, or a virus. Examples Nematodes, Protozoa and Algae.