The groups of insecticides that inhibit respiration

The groups of insecticides that inhibit respiration are a class of chemicals designed to disrupt the cellular respiration processes in insects. These insecticides affect the main components of the mitochondrial respiratory chain, leading to a decrease in energy production efficiency and, ultimately, to the death of insects. Respiratory inhibitors can block various stages of the respiratory process, including the electron transport chain and enzymatic reactions responsible for substrate oxidation and atp synthesis.

Goals and importance of use in agriculture and horticulture

The primary goal of using insecticides that inhibit respiration is to effectively control insect pest populations, which contributes to increased yields and reduced product losses. In agriculture, these insecticides are used to protect cereal crops, vegetables, fruits, and other cultivated plants from various pests such as mealybugs, aphids, pupae, and others. In horticulture, they are applied to protect ornamental plants, fruit trees, and shrubs, maintaining their health and aesthetic appeal. Due to their specificity and high effectiveness, respiratory inhibitors are an important tool in integrated pest management (ipm), ensuring sustainable and productive agriculture.

Relevance of the topic

With the growing world population and increasing food demand, effective pest management has become critically important. Insecticides that inhibit respiration offer unique mechanisms of action that can be used to fight resistant pest species. However, improper use of these insecticides can lead to the development of resistance in pests and negative environmental consequences, such as reduced populations of beneficial insects and environmental contamination. Therefore, it is important to study the mechanisms of action of respiratory inhibitors, their impact on ecosystems, and develop sustainable methods of their application.

History

The history of insecticide groups that inhibit respiration involves the development of chemicals that affect the cellular respiration of insects, suppressing their ability to use oxygen for metabolic processes. These insecticides became an important tool in pest control, but as their use grew, ecological issues and resistance problems emerged. This article will discuss the history of this group of insecticides, including key stages, chemicals, and their usage.

1. Early research and developments

In the 1940s, scientists began exploring ways to influence cellular respiration to create more effective insecticides. These studies led to the emergence of a range of chemicals that inhibited key enzymes in the respiratory chain in insect mitochondria, disrupting their metabolism and ultimately leading to their death.

Example:
Dimethoate – one of the first insecticides affecting respiration. It was developed in the 1950s and demonstrated high efficacy against various pests.

2. 1950s-1960s: the emergence of new products

In the 1950s and 1960s, scientists continued developing chemicals that affected cellular respiration. This led to the appearance of new insecticides that were widely used in agriculture to fight various pests such as aphids, mites, and other insects.

Example:
Phosmet – an organophosphorus insecticide that inhibited insect respiration by disrupting the normal functioning of mitochondria. This insecticide was widely used in agriculture, especially in the fight against vegetable crop pests.

3. 1970s: increased ecological and toxicological issues

In the 1970s, the use of insecticides that inhibit respiration led to increased toxicity and the emergence of ecological problems. These substances had detrimental effects not only on pests but also on beneficial insects, such as bees and predatory insects. There were also issues with the accumulation of these chemicals in ecosystems, contaminating soils and water bodies.

Example:
Acetamiprid – a pyrethroid insecticide that affects both respiration and the nervous system of insects. Initially developed for pest control, it later raised concerns regarding its impact on ecosystems.

4. 1980s-1990s: development of resistance

With the increased use of insecticides inhibiting respiration, resistance problems emerged. Insects began to adapt to the effects of these products, reducing their effectiveness. To combat resistance, new insecticide combinations were developed, and strategies such as rotating different types of insecticides were proposed.

Example:
Clofentezine – an insecticide that affected insect respiration, widely used in the 1990s, but its effectiveness decreased due to resistance that developed in some pest populations.

5. Modern approaches: selectivity and sustainability

In recent decades, researchers have focused on developing more selective insecticides that target only pests while minimizing effects on beneficial insects and other organisms. This has led to increased research on combined approaches that incorporate not only chemical insecticides but also biological and mechanical pest control methods.

Example:
Spinosad – a biological insecticide using enzymes that affect the insect nervous system and disrupt respiration. This product became popular due to its high efficacy and reduced environmental impact.

6. Problems and perspectives

In recent years, ecological problems associated with the use of insecticides inhibiting respiration have increasingly become the subject of scientific discussions. The development of resistance in pests, as well as issues with safety and bioaccumulation of toxic substances in ecosystems, remain pressing concerns.

Current research in this area focuses on creating more environmentally safe and effective products that minimize the impact on beneficial insects and the environment.

Example:
Neem oil-based products – used for ecological pest control. While they do not directly inhibit respiration, they are a safe alternative for controlling insect populations.

Problems of resistance and innovations

The development of resistance in insects to insecticides that inhibit respiration has become one of the main problems associated with their use. Pests exposed to repeated treatments with these insecticides can evolve to become less susceptible to their effects. This requires the development of new insecticides with different mechanisms of action and the implementation of sustainable pest control methods, such as rotating insecticides and using combined products. Modern research is aimed at creating respiratory inhibitors with improved properties, reducing the risks of resistance development and minimizing environmental impact.

Classification

Insecticides that inhibit respiration are classified according to various criteria, including chemical composition, mode of action, and spectrum of activity. Major groups of insecticides that inhibit respiration include:

• Rotenones: natural insecticides derived from the roots of derris and lonchocarpus plants. They block complex i in the mitochondrial respiratory chain, preventing electron transfer and atp production.
• Phenylphosphonates: synthetic compounds that inhibit various complexes of the respiratory chain, disrupting cellular respiration in insects.
• Hungarian inhibitors: modern synthetic insecticides specifically designed to block respiratory enzymes in insects.
• Thiocarbamates: a group of insecticides that affect metabolic processes, including cellular respiration.
• Strichnobenzones: insecticides that block complex iii in the mitochondrial respiratory chain, leading to the cessation of cellular respiration and insect death.

Each of these groups has unique properties and modes of action, allowing their use in various conditions and for different cultivated plants.

Insecticides that inhibit respiration can be classified by several features:

Classification by chemical structure

• Cyanides: block electron transport in mitochondria, disrupting cellular respiration.
• Organophosphorus compounds: block respiratory chain enzymes, such as cytochromes, inhibiting normal mitochondrial function.
• Benzoate compounds: interfere with metabolic processes in cells, preventing normal respiration.
• Nitropyrenes: actively block respiratory enzymes in insect mitochondria, disrupting their energy exchange.

Classification by mode of action

• Interference with respiratory chains: block enzymes responsible for oxygen transport and energy production, leading to oxygen starvation.
• Inhibition of oxidation and phosphorylation: block processes related to glucose oxidation and atp synthesis, causing an energy deficit and insect death.
• Electron transfer blockage: inhibit enzymes involved in electron transfer in mitochondria, disrupting the respiratory process.

Classification by area of application

• Agriculture: used to protect crops from pests such as fruit flies, beetles, aphids, mites, and other insects that damage plants.
• Warehouse storage and food security: used to eliminate pests such as bedbugs, cockroaches, and flies that can damage food products and lower the quality of stored goods.
• Forestry: used to control pests affecting forest crops and timber.

Classification by toxicity and safety

• Toxic to insects, but relatively safe for mammals: these insecticides harm only insects and have minimal effects on mammals when applied correctly.
• Highly toxic to all organisms: some insecticides affecting respiration can be dangerous to both insects and animals and humans if safety measures are not followed.
• Safe for humans and animals but effective against insects: these insecticides are used in places where safety is important, such as households and food storage areas.

Examples of products

• Organophosphorus insecticides (e.g., malathion, parathion): block insect respiratory chain enzymes and are used for agricultural crop protection.
• Cyanides (e.g., hydrogen cyanide): active substances that interfere with insect metabolism and block respiration, used in various forms to destroy pests in warehouses and food storage.
• Nitropyrenes (e.g., nitrapyrine): effective against many insects and widely used in agriculture.

Mechanism of action

How insecticides affect the nervous system of insects

• Insecticides that inhibit respiration affect the insect nervous system indirectly by disrupting energy metabolism. Since nerve cells heavily rely on atp for maintaining membrane potential and transmitting nerve impulses, disruption of cellular respiration leads to a decrease in atp levels. This causes depolarization of nerve membranes, impairing nerve impulse transmission, and leading to insect paralysis.

Effect on insect metabolism

• Disruption of cellular respiration leads to a breakdown in metabolic processes, such as feeding, reproduction, and movement. The reduced efficiency of cellular respiration decreases atp production, slowing vital functions and reducing pest activity and viability. As a result, insects become less capable of feeding and reproducing, which helps control their populations and prevent damage to plants.

Molecular mechanisms of action

• Insecticides that inhibit respiration block various complexes of the mitochondrial respiratory chain. For example, rotenone blocks complex i (nicotinamide-adenine dinucleotide dehydrogenase), preventing electron transfer from nadh to coenzyme q. This halts the electron transport chain, reduces atp production, and leads to nadh accumulation, causing an energy crisis in insect cells. Other insecticides, such as phenylphosphonates, can inhibit complex iii (cytochrome b-c1 complex), disrupting electron transfer and causing similar effects. These molecular mechanisms ensure high effectiveness of respiratory inhibitors against various insect pests.

Difference between contact and systemic action

• Insecticides that inhibit respiration can have both contact and systemic effects. Contact insecticides act directly when they come into contact with insects, penetrating the cuticle or respiratory pathways, blocking respiratory enzymes, and causing paralysis and death on-site. Systemic insecticides penetrate plant tissues and spread throughout the plant, providing long-term protection against pests that feed on different parts of the plant. Systemic action allows for longer pest control and broader application, ensuring effective crop protection.

Examples of products in this group

Rotenone:

• Mode of action: blocks complex i of the mitochondrial respiratory chain, preventing electron transfer and atp production.
• Examples of products: rotenone-250, agroroten, stroyoten
• Advantages: high effectiveness against a wide range of insect pests, natural origin, relatively low toxicity for mammals.
• Disadvantages: high toxicity to aquatic organisms, environmental hazards, limited application near water bodies.

Phenylphosphonates:

• Mode of action: inhibit complexes of the mitochondrial respiratory chain, disrupting electron transfer and atp production.
• Examples of products: phenylphosphonate-100, agrofenil, breathing complex
• Advantages: high efficacy, wide range of action, systemic distribution.
• Disadvantages: toxicity to beneficial insects, potential for resistance in pests, environmental contamination.

Hungarian inhibitors:

• Mode of action: block specific enzymes in the mitochondrial respiratory chain, disrupting cellular respiration and leading to insect death.
• Examples of products: ungarik-50, inhibitus, agroungar
• Advantages: specific action, high effectiveness against resistant pest species, low toxicity for mammals.
• Disadvantages: high cost, limited spectrum of action, risk of soil and water contamination.

Thiocarbamates:

• Mode of action: affect metabolic processes, including cellular respiration, by inhibiting specific respiratory enzymes.
• Examples of products: thiocarbamate-200, agrothio, metabrom
• Advantages: high efficacy against a wide range of insects, systemic action, resistance to degradation.
• Disadvantages: toxicity to beneficial insects, potential accumulation in soil and water, development of resistance in pests.

Strichnobenzones:

• Mode of action: block complex iii of the mitochondrial respiratory chain, disrupting electron transfer and stopping atp production.
• Examples of products: strichnobenzone-150, agrostikh, complex-b
• Advantages: high effectiveness against a wide range of insect pests, systemic action, resistance to photodegradation.
• Disadvantages: toxicity to aquatic organisms, potential environmental contamination, development of resistance in pests.

Insecticides and their environmental impact

Effect on beneficial insects

• Insecticides that inhibit respiration have a toxic effect on beneficial insects, including bees, wasps, and other pollinators, as well as predatory insects that naturally control pest populations. This leads to a reduction in biodiversity and disruption of the ecosystem balance, which negatively affects agricultural productivity and biodiversity.

Residual insecticides in soil, water, and plants

• Insecticides that inhibit respiration can accumulate in the soil for long periods, especially in conditions of high humidity and temperature. This leads to contamination of water sources through runoff and infiltration. In plants, insecticides are distributed throughout all parts, including leaves, stems, and roots, which promotes systemic protection but also leads to the accumulation of insecticide in food products and soil, potentially impacting human and animal health.

Photostability and degradation of insecticides in nature

• Many insecticides that inhibit respiration have high photostability, which increases their duration of action in the environment. This prevents rapid degradation by sunlight and promotes their accumulation in soil and aquatic ecosystems. High resistance to degradation complicates the removal of insecticides from the environment and increases the risk of their impact on non-target organisms.

Biomagnification and accumulation in food chains

• Insecticides that inhibit respiration can accumulate in the bodies of insects and animals, moving up the food chain and causing biomagnification. This leads to higher concentrations of the insecticide at the upper levels of the food chain, including predators and humans. Biomagnification of insecticides causes serious ecological and health problems, as accumulated insecticides can cause chronic poisoning and health issues in animals and humans.

The problem of insect resistance to insecticides

Causes of resistance development

• Resistance development in insects to insecticides that inhibit respiration is caused by genetic mutations and the selection of resistant individuals through repeated use of the insecticide. Frequent and uncontrolled use of these insecticides promotes the rapid spread of resistant genes among pest populations. Inadequate adherence to dosages and application schedules also accelerates the resistance development process, making the insecticide less effective.

Examples of resistant pests

• Resistance to insecticides that inhibit respiration has been observed in various species of insect pests, including whiteflies, aphids, mites, and some moth species. These pests show decreased sensitivity to insecticides, making them harder to control and leading to the need for more expensive and toxic chemicals or a shift to alternative control methods.

Methods of preventing resistance

• To prevent resistance development in insects to insecticides that inhibit respiration, it is necessary to rotate insecticides with different mechanisms of action, combine chemical and biological control methods, and apply integrated pest management strategies. It is also important to follow recommended dosages and application schedules to avoid selecting resistant individuals and maintain the effectiveness of the products in the long term.

Safe application guidelines for insecticides

Solution preparation and dosages

• Proper solution preparation and accurate dosing of insecticides are critical for their effective and safe application. It is important to strictly follow the manufacturer’s instructions for preparing solutions and applying dosages to avoid overdosing or insufficient treatment of plants. Using measuring tools and quality water helps ensure accurate dosing and effective treatment.

Use of protective equipment when handling insecticides

• When working with insecticides that inhibit respiration, it is necessary to use appropriate protective gear, such as gloves, masks, goggles, and protective clothing, to minimize the risk of insecticide exposure to the human body. Protective gear helps prevent contact with skin and mucous membranes, as well as inhalation of toxic insecticide vapors.

Recommendations for treating plants

• Treat plants with insecticides that inhibit respiration during morning or evening hours to avoid affecting pollinators such as bees. Avoid treatment in hot and windy weather, as this may lead to spraying the insecticide onto beneficial plants and organisms. It is also recommended to consider the plant growth phase, avoiding treatment during active flowering and fruiting periods.

Observing waiting periods before harvesting

• Observing the recommended waiting periods before harvesting after applying insecticides that inhibit respiration ensures product safety and prevents insecticide residues from entering food products. It is important to follow the manufacturer’s instructions on waiting periods to avoid poisoning risks and ensure product quality.

Alternatives to chemical insecticides

Biological insecticides

• Using entomophages, bacterial, and fungal preparations represents an environmentally safe alternative to chemical insecticides that inhibit respiration. Biological insecticides, such as bacillus thuringiensis, effectively control insect pests without harming beneficial organisms and the environment. These methods promote sustainable pest management and the preservation of biodiversity.

Natural insecticides

• Natural insecticides, such as neem oil, tobacco infusions, and garlic solutions, are safe for plants and the environment and can be used to control pests. These remedies have repellent and insecticidal properties, allowing effective control of insect populations without synthetic chemicals. Natural insecticides can be used in combination with other methods for optimal results.

Pheromone traps and other mechanical methods

• Pheromone traps attract and kill insect pests, reducing their numbers and preventing spread. Other mechanical methods, such as sticky traps and barriers, also help control pest populations without the use of chemicals. These methods are effective and environmentally safe ways to manage pests.

Examples of popular insecticides from this group

Product name	Active ingredient	Mode of action	Application area
Rotenone	Rotenone	Blocks complex i of the mitochondrial respiratory chain, preventing electron transfer and atp production	Vegetable crops, fruit trees
Phenylphosphonates	Phenylphosphonate	Inhibits respiratory chain complexes, disrupting electron transfer and atp production	Cereal crops, vegetables, fruits
Hungarian inhibitors	Hungarian inhibitor	Blocks specific respiratory enzymes in mitochondria, disrupting cellular respiration and causing insect death	Vegetables and fruit crops, ornamental plants
Thiocarbamates	Thiocarbamate	Inhibits specific enzymes of the mitochondrial respiratory chain, affecting cellular respiration	Vegetable crops, cereals, fruits
Strichnobenzones	Strichnobenzone	Blocks complex iii of the mitochondrial respiratory chain, disrupting electron transfer and halting atp production	Vegetable, fruit, and ornamental crops

Advantages and disadvantages

Advantages:

• High effectiveness against a wide range of insect pests
• Specific action, minimal impact on mammals
• Systemic distribution in plants, ensuring long-term protection
• Potential for combining with other control methods to enhance effectiveness

Disadvantages:

• Toxicity to beneficial insects, including bees and wasps
• Potential for developing resistance in insect pests
• Potential contamination of soil and water
• High cost of some products compared to traditional insecticides

Risks and precautions

Impact on human and animal health

• Insecticides that inhibit respiration can have serious effects on human and animal health when used improperly. When ingested or absorbed into the human body, they can cause poisoning symptoms such as dizziness, nausea, vomiting, headaches, and, in extreme cases, seizures and loss of consciousness. Animals, especially pets, are also at risk of poisoning if insecticide comes into contact with their skin or if they ingest treated plants.

Symptoms of poisoning by insecticides

• Symptoms of poisoning by insecticides that inhibit respiration include dizziness, headaches, nausea, vomiting, weakness, difficulty breathing, seizures, and loss of consciousness. If the insecticide gets into the eyes or on the skin, irritation, redness, and burning may occur. If the insecticide is ingested, immediate medical attention is required.

First aid for poisoning

• If poisoning by insecticides that inhibit respiration is suspected, it is important to immediately stop contact with the insecticide, rinse the affected skin or eyes with plenty of water for at least 15 minutes, and seek medical attention. If inhaled, move to fresh air and consult a doctor. If the insecticide is swallowed, call emergency services immediately and follow the first aid instructions provided on the product label.

Pest prevention

Alternative pest control methods

• Cultural methods such as crop rotation, mulching, removing infected plants, and introducing resistant plant varieties help prevent pest infestations and reduce the need for insecticides that inhibit respiration. These methods create unfavorable conditions for pests and strengthen plant health. Biological control methods, including the use of entomophages and other natural predators of insect pests, are also effective preventive measures.

Creating unfavorable conditions for pests

• Proper watering, removal of fallen leaves and plant debris, and maintaining a clean garden and vegetable patch create unfavorable conditions for pest reproduction and spread. Installing physical barriers, such as nets and borders, helps prevent pests from accessing plants. It is also recommended to regularly inspect plants and promptly remove damaged parts, reducing their attractiveness to pests.

Conclusion

Rational use of insecticides that inhibit respiration plays an important role in plant protection and increasing the yield of agricultural and ornamental plants. However, it is necessary to follow safety guidelines and consider ecological aspects to minimize the negative impact on the environment and beneficial organisms. An integrated pest management approach that combines chemical, biological, and cultural control methods promotes sustainable agricultural development and biodiversity conservation. It is also important to continue research on the development of new insecticides and control methods aimed at reducing risks to human health and ecosystems.

Frequently asked questions (FAQ)

1. What are insecticide groups that inhibit respiration and what are they used for?

Insecticide groups that inhibit respiration are a class of chemicals designed to disrupt cellular respiration processes in insects. They are used to control insect pest populations in agriculture and horticulture, increasing yields and preventing damage to cultivated plants.

2. How do insecticides that inhibit respiration affect the nervous system of insects?

These insecticides affect the nervous system of insects indirectly by disrupting energy metabolism. Disruption of cellular respiration leads to decreased atp levels, which causes depolarization of nerve membranes, impaired nerve impulse transmission, and paralysis of the insects.

3. Are insecticide groups that inhibit respiration harmful to beneficial insects such as bees?

Yes, these insecticides are toxic to beneficial insects, including bees and wasps. Their application requires strict adherence to regulations to minimize the impact on beneficial insects and prevent biodiversity loss.

4. How can resistance in insects to insecticides that inhibit respiration be prevented?

To prevent resistance, it is necessary to rotate insecticides with different modes of action, combine chemical and biological control methods, and follow recommended dosages and application schedules.

5. What ecological problems are associated with the use of insecticides that inhibit respiration?

The use of these insecticides leads to a reduction in beneficial insect populations, soil and water contamination, and the accumulation of insecticides in food chains, causing significant ecological and health problems.

6. Can insecticides that inhibit respiration be used in organic farming?

No, these insecticides do not meet organic farming standards due to their synthetic origin and potential negative impact on the environment and beneficial organisms.

7. How should insecticides that inhibit respiration be applied for maximum effectiveness?

Strictly follow the manufacturer’s instructions for dosages and application schedules, treat plants during the morning or evening hours, avoid applying during pollinator activity periods, and ensure even distribution of the insecticide on the plants.

8. Are there alternatives to insecticides that inhibit respiration for pest control?

Yes, there are biological insecticides, natural remedies (such as neem oil, garlic solutions), pheromone traps, and mechanical control methods that can serve as alternatives to chemical insecticides that inhibit respiration.

9. How can the environmental impact of insecticides that inhibit respiration be minimized?

Use insecticides only when necessary, follow recommended dosages and application schedules, avoid contamination of water sources with insecticides, and apply integrated pest control methods to reduce reliance on chemical products.

10. Where can insecticides that inhibit respiration be purchased?

These insecticides are available in specialized agro-technical stores, online retailers, and from plant protection product suppliers. Before purchasing, it is important to verify the legality and safety of the products being used.