DISEASE CONTROL

DISEASE CONTROL Measures should be taken in time to help control the onset and spread of diseases in plants.

Rotation of Crops Pathogens (organisms causing dis­ease) are specific to particular plants. Replacement of one crop by another crop reduces the chance of disease.

Rogueing Infected plants should be uprooted or burnt and removed.

Seed Treatment The seeds should be treated with dilute solution of fungicides and pesticides before sowing. This would eradicate the disease germs which stick on the seed surface.

Biological Control Predator insects may be released to kill the insects in a natural way.
Proper Manuring In cases such as rust, the excess or deficiency of nitrogen fertilisers increases the susceptibility of the plants. Hence, it is necessary to maintain the balance of nitrogen and phosphorus fertilisers.

Using Chemicals Crop losses can be reduced by the use of pesticides, fungicides, and insecticides. But they must be used with care. They should be biodegradable.

Systemic Insecticides These compounds when applied to the leaves, stems and sometimes the roots of plants, are absorbed and translocated in the plants in the course of normal nutrition. Their concentrations are safe for the plant but fatal for the insects feeding on the plants.

Weed killers Herbicides used to control selectively unwanted vegetation on agricultural land may act either selectively, or they may be applied before the crop emerges.