What is a pest?
There are thousands of organisms in the world but we do not consider all of them pests. When does an organism become a pest? When the population of an organism reaches a level where it can cause considerable damage it becomes a pest. An agricultural pest is an organism that causes extensive damage to agricultural crops thereby reducing yield. They can be either crop pests or storage pests depending on whether they destroy crops on the field or during storage.
How do we control pests?
In nature there exists a balance in the population of all the organisms inhabiting it. If left undisturbed this balance is maintained. However, humans have interfered and altered nature and therefore disturbed the balance. This disruption has caused some organisms to reproduce at very high rates and become pests causing extensive damage. Under these circumstances chemicals are used to control pests, as natural methods of pest control become ineffective. The chemicals used to control pests are called pesticides. Pesticide is a common name for a whole range of plant protection chemicals like fungicides, weedicides, insecticides, fumigants.
The Food Chain:
All living organisms are dependent on plant, either directly or indirectly, for their survival. Plants use the energy of the sun to produce food. They are therefore called producers. The plant-eating animals (herbivores) feed on plants and depend directly on them for existence and growth. These are called primary consumers. The meat-eating animals (carnivores) feed and depend on the herbivores for their survival. They are called secondary consumers. Thus, each organism is dependent and connected to another. This is called the food chain. In nature there exists a balance in the populations of all organisms. Even a slight disturbance at one level affects the entire food chain. We humans have disrupted the main and theefore the balance in many ways. Most of the problems we face today can be attributed to this.
Let us take the example of a food chain in an agro-ecosystem. The plants in the field are producers, the insects that feed on these plants are the primary consumers and the birds and other organisms that feed on these insects are the secondary consumers. Under natural conditions, the populations of all organisms are kept under control ensuring a healthy system and therefore consistent yields from the land.
However, agricultural systems no longer operate under natural conditions. In our haste to increase yields to feed a growing population we have introduced innumerable chemicals (fertilizers and plant protection chemicals) into the agricultural system. Today we are facing the consequences-decreasing yields, pests resurgence, and a varienty of prblems related to health besides pollution and contamination of our natural resources.
What causes this sudden increase in the population of certain insects?
In nature we find that every pest has a predator ) an organism which feeds on the pest) which helps to keep pest populations in check. A sudden decrease in the predator population could lead to an increase in pest population causing extensive damage to crops.
How do we control pests?
In nature there exists a balance in the population of all the organisms inhabiting it. If left undisturbed this balance is maintained. However, humans have interfered and altered nature and therefore disturbed the balance. This disruption has caused some organisms to reproduce at very high rates and become pests causing extensive damage. Under these circumstances chemicals are used to control pests, as natural methods of pest control become ineffective. The chemicals used to control pests are called pesticides. Pesticide is a common name for a whole range of plant protection chemicals like fungicides, weedicides, insecticides, fumigants.
The Food Chain:
All living organisms are dependent on plant, either directly or indirectly, for their survival. Plants use the energy of the sun to produce food. They are therefore called producers. The plant-eating animals (herbivores) feed on plants and depend directly on them for existence and growth. These are called primary consumers. The meat-eating animals (carnivores) feed and depend on the herbivores for their survival. They are called secondary consumers. Thus, each organism is dependent and connected to another. This is called the food chain. In nature there exists a balance in the populations of all organisms. Even a slight disturbance at one level affects the entire food chain. We humans have disrupted the main and theefore the balance in many ways. Most of the problems we face today can be attributed to this.
Let us take the example of a food chain in an agro-ecosystem. The plants in the field are producers, the insects that feed on these plants are the primary consumers and the birds and other organisms that feed on these insects are the secondary consumers. Under natural conditions, the populations of all organisms are kept under control ensuring a healthy system and therefore consistent yields from the land.
However, agricultural systems no longer operate under natural conditions. In our haste to increase yields to feed a growing population we have introduced innumerable chemicals (fertilizers and plant protection chemicals) into the agricultural system. Today we are facing the consequences-decreasing yields, pests resurgence, and a varienty of prblems related to health besides pollution and contamination of our natural resources.
What causes this sudden increase in the population of certain insects?
In nature we find that every pest has a predator ) an organism which feeds on the pest) which helps to keep pest populations in check. A sudden decrease in the predator population could lead to an increase in pest population causing extensive damage to crops.
