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As much as 40% of the food grown for human consumption is ruined by pests.

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Introduction

Pest Control As much as 40% of the food grown for human consumption is ruined by pests. Pests such as aphids, mealy bugs, whitefly and red spider mites that make their habitat in fields amongst the plants that we harvest for food. Chemical insecticides are one solution to the pest problem. They are sprayed on to the fields and are usually specific to kill only the insects that are considered pests of the plants. However, this is only a short-term solution of pest control as after a period of time, the pests build up a resistance to the chemicals. The effect of the pesticide is then diminished, so farmers use a more concentrated pesticide to kill off the pests. Even though increasing the concentration of the chemical pesticide will kill the pests shot term, it will reach a point where it will start to effect insects other than the ones it was specifically designed to kill. ...read more.

Middle

Farmers often uproot hedgerows to make more area for growing crops and to make it easier for the manoeuvre of large pieces of machinery. Hedges provide the ideal habitats for predators and without them, they are unable to survive or reach areas in the centre of large fields where pests are inhabitants. Another form of pest control is now being used which does not involve the use of harmful pesticides. It is known as biological control. It is a way of interfering with a pest's ecological status. There are companies that package the larvae of useful predators in to sachets, which can be left amongst plants. The predators can then make their habitats, using the pests as their main food source. This form of pest control is eco-friendly but does have its disadvantages. It can take along time (up to 18 months) ...read more.

Conclusion

Screwworm flies are flesh-eating insects that lay their eggs in to the wounds of warm-blooded animals, including humans. The larvae then feed on the flesh, which can then get infected, causing the animal to die. These pests have caused havoc in pastoral farms in tropical countries such as Indonesia. They are resistant to pesticides, have no known predators and have a life cycle that allows them to breed incredibly quickly. However, a solution to the problem of the screwworm fly has been found. There is a factory that breed screwworm fly in cages. The larvae are collected are collected at a very specific stage in their life cycle and are subjected to a source of gamma radiation. This makes them sterile. The infertile larvae are then put amongst the population. This stops them from breeding so they will eventually die out. This is an expensive procedure but it is very effective. A simple solution to the problem of pest control would be for farmers to stop using chemical pesticides. However many are reluctant to do so, usually due to ignorance. ...read more.

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