When a plant has a high level of nitrogen, its leaves turn dark blue-green, a colour that best promotes photosynthesis. This is the process whereby light energy is collected by the plant and converted to starches and sugars, which are then used for plant growth.
When the level of nitrogen in the plant is low, the leaves have a palegreen colour and could even be yellow in extreme cases. Photosynthesis will be insufficient and the plant will therefore not grow properly. In the case of maize and grain sorghum, an inverted V-shaped pattern on the leaf tips is a sign of a nitrogen deficiency. The leaf edges die off, inhibiting plant growth.
Nitrogen occurs naturally in the soil and in the atmosphere. Legumes work with bacteria to fix (trap) nitrogen and make it available to the plant.
FERTILISERS
This story is from the May 07, 2021 edition of Farmer's Weekly.
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This story is from the May 07, 2021 edition of Farmer's Weekly.
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