Discuss the advantages and disadvantages of the methods that can be used to control agricultural pests Pest control refers to the regulation or management of pests; this is often the complete removal or a reduction in the amount of pests. In agriculture pests are either in the form of weeds or insects that damage or reduce the quality or quantity of crop yield and decrease profit margins.There is often need for pest control when there is an increase in demand. One of the most effective ways of removing weeds is burning as it instantly destroys surface growth and therefore this method is relatively quick and has no residual pollution however it is not as effective on deep rooted plants e. g.
the dandelion. Also in terms of controlling several fields it can be quite time and labour intensive and therefore quite an expensive overhead.Another direct way of managing weeds is to physically remove them or cut/mow them, this should completely remove the plant but is not 100 % efficient for removing the whole plant especially with deeply rooted plants; this method like burning is quite labour intensive and slow. Herbicides can also be used to control pests, an herbicide is a substance used to kill unwanted plants. On contact it burns the top of the leaf by by removing the cuticle and disrupting cell membranes. These are very effective but can be mobile in high levels of water via leaching or runoff they now have the potential to pollute water stores.
Natural predators can also be introduced to remove the weed this is affective over time as no resistance can be developed an example here would be birds as predators and worms as pests or caterpillars and parasitic wasps. Crops can also be rotated this prevents a build up in pest population as it changes soil culmination which disrupts weeds, unfortunately this does not work with the monoculture style of agriculture. Mulching is a technique of pest management where materials such as bark, stones or polythene are placed over the top of weed to exclude light and make the weed run out of food.With insect pests they can be controlled using pheromone traps where pests are drawn to traps through sent, these don’t have a universal impact as they are gender and species specific, however if one gender is significantly reduced in population the birth rate of pests will decrease. Companion planting is a technique where plants with strong odors are planted close to other crops to mask their odors and stop the attraction of pests; this works instantly but can reduce the yield of the desired crop.
