YIELD MATTERS!

In the production of food, yield always matters.  An increase in yield means

• less land that needs to be cultivated in order to produce the same amount of food
• less energy expenditure
• less consumption of fossil fuels
• less CO2 production

Since the majority of the agricultural work done in resource-poor countries is done by women, increased yields also means less time spent in the fields for women and more time at home with children and in the preparation of food.

Yield x 2 = Area of Cultivation/2 and Energy/2

The potential impact of increased yields is unlimited!

How does one go about increasing yields?

In this article we will look at various ways of increasing yields in resource-poor countries with pre-commercial agriculture.  Some of these include:

• changes in soil preparation for planting
• changes in the way in which crops are planted
• changes in the tools that are used for soil preparation
• changes in methods of weed control
• changes in the tools that are used for weed control
• evaluation of soil nutrients either scientifically or through experimental plots
• observation of plant diseases
• selection of healthy plants for seed purposes (cultivars)
• better seed storage
• goat control (and cows, pigs, sheep etc.)
• erosion control

We will look at these and other subjects in the lines that follow.

SOIL PREPARATION

Zero-tillage (Direct Planting)

There is a trend in many resource-rich countries to agriculture without tilling the soil.  Zero-tillage is a method of soil preparation and tilling which disturbs the soil as little as possible, essentially by not ploughing the field.  The crop is planted directly into a seedbed which has not been tilled since the harvest of the previous crop.

Zero tillage is most beneficial in dry, tropical soils and less beneficial in cool, moist soils.  The benefits of zero-tillage include:

• Conservation of soil moisture
• Reduction of soil erosion by the wind since the architecture of the soil is not disturbed
• Reduction of agricultural labour
• Earthworms and other biological organisms are left alone to live and manipulate the soil by creating tunnels.  This allows for the movement of air and water through the soil and results in better plant growth.
• Reduction of soil compaction.  The repetitive tilling of the soil lead to a hard, densely packed soil.
• Increased soil organic matter which means better soil structure and more available nutrients for plant growth.  Tilling ‘burns’ organic matter away.