Select your language

Suggested languages for you:
Log In Start studying!
StudySmarter - The all-in-one study app.
4.8 • +11k Ratings
More than 3 Million Downloads
Free
|
|

All-in-one learning app

  • Flashcards
  • NotesNotes
  • ExplanationsExplanations
  • Study Planner
  • Textbook solutions
Start studying

Pest Control in Agriculture

Save Save
Print Print
Edit Edit
Sign up to use all features for free. Sign up now

The word 'pest' is thrown around a lot in everyday life. You would normally call a mischievous puppy or your little sibling one, but pest is an important term in the agricultural world too! Owing to the name, pests are species which disturb the productivity of agricultural environments. This can mean anything from a caterpillar eating crops for breakfast or wolves preying on unknowing sheep at night. This article will cover the importance of pest control in agriculture, some different methods of controlling pests, and the dangers of inappropriate pest control.

The Meaning of Pest Control in Agriculture

Pest control in agriculture is the deterrence or extermination of species threatening agricultural productivity. Farms are often businesses and depend on output so that the workers can earn money and fund their lives. Therefore, any factors affecting produce must be acted on swiftly and in a cost-effective way. Here are some examples of agricultural pests you should know.

  • Weeds are invasive plants that take nutrients, water, and space from the desired crops.
  • Locusts are probably the most dangerous of all agriculture pests. Small in stature, these insects can eat their bodyweight in crops in a day and often swarm in the millions. Locust swarms have devastated agricultural land for centuries.
  • Aphids and whiteflies feed on the sap of plants meaning they lack nutrients to build other plant structures. They also feed on the flowers and carry dangerous diseases and viruses.
  • Colorado potato beetles get their names from their love for potatoes, but these insects will feed on various vegetation. They are most dangerous because of their innate ability to evolve resistance to many different pesticides quickly.
  • Corn rootworms, as the name suggests, feed on the roots of corn in their larval stage. This reduces the ability of the roots to absorb water, and yield decreases.

Figure 1: swarms of locusts are the most dangerous agricultural pest

Importance of Pest Control in Agriculture

Here's why keeping on top of pests is essential for agricultural workers wanting to maintain a productive farm:

  • Improving yield: insects, birds, and small animals feeding on crops reduce the yearly output of these crops and, therefore, the amount of money a farm makes.
  • Animal and crop health: disease-spreading insects, rodents and parasites can cause disease to spread between crops and livestock. Dangerous diseases can kill off animals and plants, while more minor ones will slow down growth and reduce yields.
  • Contamination of produce: the ruining of produce that is ready to be transported to shops is probably the most aggravating way pests can impact agriculture (e.g., disease-carrying rodents like mice and rats). The long process of cultivating plants or rearing livestock is wasted if pests infest storage and transport facilities.
  • Unbalanced ecosystems: pests with access to an abundant resource (such as a field of crops) may increase in numbers rapidly. This can disturb the equilibrium in ecosystems, where these pests may predate or compete with other species which do not have access to the same amount of resources.

Chemical Pest Control

Chemical use in pest control became popular in agriculture during the 18th and 19th centuries, even though workers were not knowledgeable of the effects of the chemicals they were using. Because of extensive research, more refined chemicals are used today, and farmers know the possible complications of applying them. Let's have a look at some agrochemicals:

Agrochemicals help farmers in protecting their crops from pests and diseases. They also play a role in optimising crop yields and improving soil fertility.

Insecticides

These are chemicals which specifically exterminate or deter insects. Insecticides can either be repellent or non-repellent. Repellents are applied to the plant and will give off unpalatable smells or pheromones specific to the pest species. In contrast, non-repellents are spread over a large area and directly exterminate the pest. Repellents require a regular application which can be time-consuming, while non-repellents are quick and straightforward but can contaminate soil and potentially poison crops.

Pheromones are chemicals released into the air by animals and insects which can affect the behaviour of members of the same species. Certain insecticides try to replicate these chemicals to deter insects from crops.

Insecticides came to prominence along with the Agricultural Revolution and are one of the main reasons crop yields have improved so much over the last century. However, in recent years, ecologists have realised insecticides' knock-on effects on ecosystems. Reducing (sometimes wiping out) insect populations can affect individuals involved in interspecies relationships in the ecosystem.

Interspecies relationships include competitors, predator-prey relationships, and symbioses.

  • An example of competition is two species of plant competing for sunlight. This is because competition occurs when two species benefit from the same niche, but cannot do so at the same time.
  • Predation occurs when one species are damaged in some way since the other is feeding on it. The consuming species is the predator while the species being consumed is the prey.
  • An example of symbiosis is between the fungus and algae that make up lichen. The fungus keeps the algae moist while the algae synthesises carbohydrates that feed the fungus. This is because symbiosis benefits both species.

Fungicides

Fungi and fungal spores can be hazardous in agriculture. They can grow uncontrollably on crops and plant roots and release dangerous toxins and pathogens which damage crops irreversibly. Farmers will use fungicides to counteract them, which are made up mostly of sulphur. Processing various plants like rosemary, oregano, and tea tree can be a great way of producing natural fungicides, as chemical ones can potentially poison plants and contaminate the soil.

Mycorrhizae fungi are the exception to this rule; they actually exhibit a symbiosis with certain plants and supply them with nitrogen ions gaining carbohydrates in return.

Herbicides

Herbicides are chemicals which target weeds. These pesticides are notoriously very difficult to produce and apply because you are trying to kill a plant right next to the crops you want to grow! Herbicides are applied directly to plants or the soil and can inhibit photosynthesis or even the production of essential compounds by the plant.

Figure 2: Canadian goldenrod weed is treated with herbicides

Biological pest control

Now that governments and environmentalists are knowledgeable about the devastating effects agrochemical-contaminated soils can have when polluting aquatic ecosystems, alternative methods of controlling pests are being explored. There are three types of biological control you need to get to terms with:

  1. Importation: this method involves introducing the pest's natural enemy into the agroecosystem. Many ecological variables must be considered when implementing this method, like whether the introduced organism will survive in the ecosystem or will it cause damage to other components of the ecosystem.
  2. Augmentation: introducing more individuals to an already established species is caused augmentation. This is usually a sounder method than importation because farmers know the species is adapted to the environment and ecosystem. However, it must be considered what effect increased numbers will have on other species in the area.
  3. Conservation: this is the safest method for other species. If there are already potential biologically controlling agents in the ecosystem, pests can be controlled by providing the conditions for their numbers to be maintained and potentially increase.

The release of parasitoids effective in killing moths is a form of biological control, for example, the invasive moth, Cactoblastis cactorum (which is interestingly used as a biological control agent for weeds itself). The moth is controlled by either the introduction of parasitoids from its native home in South America or by inundation with parasitoids known to attack the moth native to Florida.

Natural Pest Control

Natural pest control methods, sometimes called organic methods, do not involve any use of artificial substances and do not disturb the balance of ecosystems. The conservation method of biological control can be described as natural. This is because ecosystem equilibrium is not being affected as the naturally occurring population is just being maintained or slightly increased rather than drastically changed. Here are some natural pest control techniques:

  • Companion planting- this involves planting crops that naturally defend each other. This could be one releasing smells that deter pests from the other or helps disguise the plant next to it.
  • Organic deterrents- many non-synthetic products comprise the chemicals actually released by plants, so they will not harm the environment.
  • Physically removing- especially in terms of weeds, simply picking and removing the pests can work too.

Figure 3: ladybugs are natural pesticides in vegetable and flower gardens

Importance of Appropriate Pest Control

We briefly covered some complications of inappropriate pest control in each section. Farmers must be considerate when applying chemicals or introducing new species to their agroecosystems because sometimes, the productivity gained from poor pest control practices is lost in other farm components. Here are some examples:

  • Soil contamination: chemical pesticides deter pests but can poison crops and reduce soil fertility. This may result in smaller yields and stunted growth in the long term.
  • Useful wild plants: during large-scale application of chemical pesticides, some harmless wildflowers and plants can be damaged. These species often sustain biodiversity in the ecosystem and help with heterogeneity in the field. Therefore, the gene pool will become smaller, and disease will spread more quickly.
  • Disturbing the ecosystem: introducing new species to counteract pests or providing the conditions for natural enemy populations to increase can negatively impact the ecosystem. These species will often have relationships with many species in the ecosystem, so increasing their numbers will disrupt the balance of these relationships.

Pest Control in Agriculture - Key takeaways

  • Pests can be very costly in agriculture. They reduce crop yield and size, spread disease, and can contaminate produce.

  • Chemical pest control involves the application of synthetic substances which aim to exterminate or deter pests.

  • Biological control involves introducing, increasing, or maintaining populations of the natural enemy to the pest.

  • Farmers must be considerate when applying chemicals or introducing new species to their agroecosystems because sometimes, the productivity gained from poor pest control practices is lost in other farm components.

  • Natural control regards organic methods that do not have any ramifications for the health of crops of livestock or the functioning of the agroecosystem.

Frequently Asked Questions about Pest Control in Agriculture

Pest control is the reduction or limiting of pest populations that reduce agricultural productivity.

Integrated pest control is the combination of various methods of pest control. such as chemical, biological, and natural, to best protect crops and livestock.

The use of pesticides to exterminate and deter pests, and the introduction of the natural enemy to the pest.

The necessity of permission before conducting pest control on public or private land.

The physical deterrence of pests through the use of barriers like fences and wires.

Final Pest Control in Agriculture Quiz

Question

What are weeds?

Show answer

Answer

Invasive, unwanted plants which take nutrients, water, and space from the desired crops.

Show question

Question

What are some examples of common agricultural pests?

Show answer

Answer

Aphids, weeds, locusts.

Show question

Question

Why is pest control important`?

Show answer

Answer

Pest control is important to improve crop yields, prevent disease, and protect soil.

Show question

Question

When did chemical pest control become popular?

Show answer

Answer

In the 18th and 19th centuries.

Show question

Question

What is the main component of fungicides?

Show answer

Answer

Sulphur.

Show question

Question

What is a herbicide?

Show answer

Answer

A chemical which kills weeds.

Show question

Question

What is a fungicide?

Show answer

Answer

A chemical which stops fungi from growing or producing dangerous pathogens.

Show question

Question

What are pheromones?

Show answer

Answer

Chemicals released by animals and insects which affect the behaviour of other species.

Show question

Question

What are the two types of insecticide?

Show answer

Answer

Repellent and non-repellent.

Show question

Question

What are the effects of repellent insecticides?

Show answer

Answer

They give off unpalatable smells or pheromones specific to the pest species.

Show question

Question

What are some examples of interspecies relationships in the ecosystem?

Show answer

Answer

Competition, predator-prey, symbiosis.

Show question

Question

What is importation biological control?

Show answer

Answer

The introduction of the natural enemy to the pest into an agroecosystem.

Show question

Question

What is conservation biological control?

Show answer

Answer

When farmers provide conditions which favour the natural enemy of the pest which already lives in the ecosystem.

Show question

Question

What is natural pest control?

Show answer

Answer

Pest control that does not involve the use of chemical fertilisers and does not affect the ecosystem.

Show question

Question

What are the impacts of inappropriate pest control?

Show answer

Answer

Poor pest control can contaminate soils, kill wanted species, and disturb ecosystem balance.

Show question

More about Pest Control in Agriculture
60%

of the users don't pass the Pest Control in Agriculture quiz! Will you pass the quiz?

Start Quiz

Discover the right content for your subjects

No need to cheat if you have everything you need to succeed! Packed into one app!

Study Plan

Be perfectly prepared on time with an individual plan.

Quizzes

Test your knowledge with gamified quizzes.

Flashcards

Create and find flashcards in record time.

Notes

Create beautiful notes faster than ever before.

Study Sets

Have all your study materials in one place.

Documents

Upload unlimited documents and save them online.

Study Analytics

Identify your study strength and weaknesses.

Weekly Goals

Set individual study goals and earn points reaching them.

Smart Reminders

Stop procrastinating with our study reminders.

Rewards

Earn points, unlock badges and level up while studying.

Magic Marker

Create flashcards in notes completely automatically.

Smart Formatting

Create the most beautiful study materials using our templates.

Sign up to highlight and take notes. It’s 100% free.