Pest and disease control in agriculture is essential to get a good yield. Wherever growers engaged in agriculture, pests attacked, destroying some or even the entire crop.
The term pest includes insects, fungi, plants, bacteria, and viruses in modern times. The efforts of humans to control pests in agriculture have a long history.
Irreversible and costly damage to crops can occur because of pests, insects, and weeds. Ways to address these issues include pesticides or biological pest control.
Farmers want to control pests and diseases to get the best products and prevent crop losses. Preventing pests and diseases is very important before they damage crops.
Chemical, Biological, cultural, and integrated pest control are four common pest and disease control methods.
Methods of Pest and Disease Control in Crops
Various methods are used in agriculture to control pests and diseases in crops.
Biological Control of Pests
The Biological or biocontrol method is a way to control pests such as mites, weeds, insects, and plant diseases by using other organisms.
It depends on prey, parasites, herbivores, or other natural mechanisms but often involves an active role of human management. This method can be an essential part of integrated pest management (IPM) programs. [1]
Beneficial living organisms such as predators or parasites are used to control pests, weeds, and harmful insects. Predatory insects feed on parasites and can limit their population. Some parasites live a part of their life inside plants and eventually kill them.
Biological pest control can occur naturally, or farmers can intentionally release predators and parasites of their own free will. So this method of pest and disease control in agriculture is effective.
Cultural Control Methods of Pests
The cultural management method to control pests and diseases in agriculture involves changing the environment not to cause problems and diseases. The cultural pest control method lowers pests’ growth, reproduction, spread, and survival. [2]
The most important types of cultural control are:
- Quarantine to prevent pests and diseases from entering a crop field
- Crop rotation
- Planting disease-resistant crop verities
- Good working and management practices.
Quarantine Method of Pest Control
Quarantine is a management strategy to prevent pests and diseases from spreading. It includes all regulatory measures taken to keep out pests or pathogens from animals or plants in an area, territory, country, or group of countries.
For instance, if animal or plant genetic resources are imported from another country or region, there is a risk that they may contain or can carry pests or pathogens that could harm agriculture.
For this reason, countries use quarantine methods to protect their agriculture and living resources from possible damage or destruction. [3]
These measures help prevent pests and diseases affecting our crops, such as berries, oranges, grapes, wheat, rice, maize, and cereals. So quarantine method is valuable and practical for pest and disease control in agriculture.
Farmers should not introduce infected plants into their fields. Inspection of plant material must be carried out and used only when a farmer is sure that they are free of pests and diseases.
Plant material they are unsure of should be quarantined and stored separately from other plants.
Also Read: Advantages of Using Fertilizers in Agriculture
Crop Rotation
Some plant families are affected by the same pests and diseases.
Crop rotation is a method of growing crops. In this method, the same crop is not planted in the same field every year; instead, different crops are planted alternately. Pests and diseases can increase if a farmer grows similar crops in the same soil every year.
This method lowers the accumulation of pests and diseases. Crop rotation interrupts the life cycle of pathogens and prevents their number.
For instance, if sprouts, cabbage, Brussels, and cauliflower (members of the brassica family) are grown every year in the same field, Club Root Disease can develop. Club Root Disease attacks roots, which interferes with plant growth.
Similar crops are grouped in crop rotation:
- Brussels, cabbage, broccoli, cauliflower, sprouts, and beets like leafy crops
- Beets, radishes, carrots, and parsnips like root crops
- Other plants and legumes like peas, beans, potatoes, leeks, celery, and green manure (including peel and oats).
There are different nutritional needs for different crops. Changing crops from year to year will reduce nutrition shortages.
Legumes provide the nitrogen that leafy green plants need in large quantities. Compared to leaf crops, root crops need more phosphorus and less nitrogen.
Diseases Resistant Plants
Plants varieties that grow despite pests and disease presence are known as disease-resistant plants. Resistance occurs when plants contain chemicals that make them unsuitable for pests and stop the disease’s spread.
Resistance can occur naturally, but scientists are still trying to identify plants resistant to certain pests or diseases. They are used for breeding.
A cheap and easy way to control plant diseases in crops with such varieties is to use disease-resistant or tolerant varieties. Their use can help reduce the use of pesticides in disease control. [4]
The following are examples:
- A breeding program is there for crab apples to develop resistance against blackheads.
- The tobacco mosaic virus (TMV) affects tobacco plants, due to which plants grow poorly and have pale, mottled leaves. Tobacco mosaic virus-resistant plants are available.
Chemical Control Methods
There are various chemical methods for pest and disease control in agriculture. These are:
Pesticide
To control pests, farmers use pesticides. These chemicals are also called insecticides.
The decision on the use of pesticides is determined as per the following:
- Type of pests that requires control
- Species and value of the crop
- Presence of beneficial insects.
Three types of pesticides to control pests are:
- Contact Pesticides
- Gastric Pesticides
- Systemic Pesticides
Contact Pesticides
Contact pesticide is a chemical made to spray directly on pests to destroy them. These pesticides can be natural, inorganic, or even organic products that usually leave behind some residues.
These include acephate (Orthene), carbaryl (Sevin), pyrethrins, and pyrethroids. These are fatal to the target.
Contact pesticides are primarily available in the form of aerosols or sprays. These pesticides are commonly used on a large scale in crops that give higher yields than small-scale crops.
Surfaces of landscapes and lawns are treated with contact pesticides. This approach is more expensive than other methods but can provide better control in smaller spaces. [5]
Stomach Pesticides
Snail pellets and slugs are forms of stomach pesticides. Pests eat (swallow)these chemicals and are killed. These types of pesticides are often set as bait.
Stomach insecticides are poisonous only if taken orally and are helpful against insects that chew or bite. The main toxins in the stomach pesticides are arsenic, for example, Paris green (copper acetate), lead arsenate, and calcium arsenate.
These pesticides are applied spray or powder to the leaves and stems of plants eaten by target insects.
Systemic Pesticides
Unlike other pesticides that remain on the leaf surface of treated plants, the plants absorb systemic pesticides and transport them to all tissues (leaves, roots, stems, and flowers, including pollen and nectar).
The most common systemic pesticides are Neonicotinoids and Fipronil which belong to the systemic neuro-active insecticides based on nicotine.
The term systemic means that these chemicals are soluble in water enough for the plant to absorb and move through its tissues. Like all transmissible chemicals in the plant, systemic insecticides act primarily in the plant’s circulatory system, including the phloem and xylem. [6]
Killing Pests by Suffocation
The suffocation method uses oils to kill pests because they cover the insects with an impermeable oil film that closes the breathing holes. Sucking insects can be controlled this way. Oils help resolve overwintering pests on plants. After winter, pests do not move much. Spraying oil on dormant plants without leaves, like apples, quickly reaches targeted pests.
Fungicides and Bactericides
Conservative fungicides and bactericides prevent the germination of fungal and bacterial spores. They form a plant protective layer so that spores placed on the plant’s surface do not grow.
It is best to apply fungicides and bactericides before bacteria and fungi grow. Metal compounds like copper and zinc are widely used to inhibit bacteria and fungi growth.
To protect plants from fungal and bacterial diseases, some oils are used, and they act in the same way as protective fungicides and bactericides.
Integrated Pest Management (IPM)
Farmers who grow crops commercially prevent and control pests and diseases to achieve the best possible plant growth. They select the most cost-effective treatment methods based on the crop types they grow and their supply market.
Integrated Pest Management (IPM) is a method where farmers use cultural, biological, and chemical combination methods to prevent or control pests and diseases.
This method was created because diseases and pests have developed resistance against chemical substances, and consumers are concerned about using chemicals on fruits and vegetables.
The IPM method depends on the natural enemy presence, existing culture management methods, and environmental factors.
Integrated Pest Management is an environmentally friendly and practical approach to controlling pests, based on a combination of common-sense practices.
This method uses up-to-date and complete information about the pest life cycle and its interactivity with the environment. [7]
Crop Monitoring
Monitoring crops for pest and disease control in agriculture is crucial for IPM programs. Crop growers regularly check the level of pests and diseases.
The threshold or pest limit is calculated for each crop type, and this value is used to determine if it should be sprayed or not. If pests are below limit levels, spraying is not profitable. Growers should spray only when the threshold is exceeded, and then the sprays are used alternately.
Conclusion
Pests, diseases, and weeds can cause costly and unrepairable losses to crops. Various methods for pest and disease control in agriculture are available like biological control, cultural control, and chemical control are used to overcome pest problems in agriculture.
Integrated Pest Management (IPM) combines biological, cultural, and chemical methods and includes crop monitoring to reduce pest damage. Integrated Pest Management aims to develop and expand practical, cost-effective, and environmentally friendly pest control policies.
