Pesticide

People use special tools to stop pests.

Pests are things that cause harm. They can be bugs or weeds. Some pests can even spread sickness.

These tools help protect our food. They stop bugs from eating plants. This helps farmers grow more food. Some tools work on the outside of a plant. Other tools move inside the plant. This makes them work even better. We must use them very carefully. This keeps people and animals safe.

Pesticides are substances used to control pests.

Pests are living things that cause harm. They can be insects, weeds, or fungi. Some pests can even spread disease.

Farmers use pesticides to protect their crops. This helps them grow more food. There are many different kinds of pesticides. Herbicides kill weeds. Insecticides kill insects. Fungicides stop fungi from growing. Some pesticides are systemic. This means they move inside a plant. Other pesticides are non-systemic. These stay on the outside of the plant. We must use them very carefully. Some pesticides can be toxic. This means they might harm humans or animals. Scientists work to make new ones. They want tools that work well but stay safe. They also try to find ways to stop pests from becoming resistant. Resistance happens when pests stop being bothered by a pesticide.

One way to help is through integrated pest management. This is a way to use many tools to keep nature in balance.

Pesticides are substances used to control pests.

A pest is any living thing that causes harm or trouble. These can include insects, weeds, fungi, and even tiny microbes. Some pests can spread diseases to humans or animals. Farmers use pesticides to protect their crops from these threats. This help allows them to grow much more food.

Many people use them to keep gardens or lawns looking nice. They can even stop termites from damaging houses. However, we must use them carefully because they can be toxic. This means they might harm humans or other living things.

Pesticides work in a few different ways. Some are non-systemic, which means they stay on the surface of a plant. These work through direct contact with the pest. Other types are called systemic pesticides. These move inside the plant through its natural paths. This allows the medicine to travel up or down the plant. Systemic pesticides are very helpful for treating seeds before they are planted. Some pesticides are also called fumigants when they are in a gas form. Scientists study how these substances disrupt a pest's body to make them work better.

People have used pesticides for a very long time. In ancient times, they used plant extracts and minerals like copper or sulfur. In the 1940s, scientists introduced new synthetic types like DDT. These were very profitable and used widely. But people soon learned that DDT stayed in the environment too long. It became a global pollutant that moved through the food chain. Because of this, many countries banned DDT in the 1970s.

Today, we try to use substances that break down quickly.

There are many specific types of pesticides to know. Herbicides kill weeds, and they make up about 50% of all use. Insecticides target insects, while fungicides stop fungi from growing. Rodenticides are used to control rodents like mice. In 2023, the world used 3.73 million tonnes of these active ingredients. Brazil was the largest user of pesticides in 2023 with 801 kilotonnes.

Even though they are more effective now, the total amount used is still increasing in many places.

Managing pests is a big job for science. One way is called Integrated Pest Management, or IPM. This method uses many different tools to keep nature in balance. Instead of spraying all the time, farmers only spray when they reach a certain level of damage. This helps stop pests from developing resistance. Resistance is when a pest stops being bothered by a pesticide.

Scientists are also working hard to develop new biopesticides. These are often cheaper and safer for the environment to use.

{ "text": "Pesticides are substances used to control pests. A pest is any organism that causes harm, a nuisance, or spreads disease. These targets include insects, weeds, fungi, rodents, and even microbes. Pesticides can be chemical or biological agents, such as a virus or bacterium.

They are essential for increasing agricultural yields by protecting crops. However, they also carry risks, such as potential toxicity to humans and other species. This balance between protection and safety is a central focus of modern science.\n\nPesticides function through various biological mechanisms. Scientists classify them by their mode of action, which is the specific way they disrupt a pest's body. Some are non-systemic, also called contact pesticides, which remain on a surface. These work through direct contact with the target organism. Other pesticides are systemic, meaning they move through the plant. They translocate through the xylem, which moves fluids upward, or the phloem, which moves fluids downward. Systemic properties are a requirement for using a pesticide as a seed treatment.\n\nThere are many specific types of pesticides categorized by their target organism. Herbicides are used to control weeds and account for about 50% of all global pesticide use. Insecticides target insects, while fungicides control fungi and oomycetes. Nematicides are used against nematodes, which are roundworms. Other specialized types include algicides for algae, avicides for birds, and rodenticides for rodents.

Some pesticides are also classified as fumigants when they are applied in a gas form.\n\nThe history of pesticides shows a shift from natural to synthetic substances. From ancient times until the 1950s, people used inorganic compounds and plant extracts. These included derivatives of copper, arsenic, and mercury, or extracts like nicotine. In the 1940s, synthetic organic compounds like the insecticide DDT and the herbicide 2,4-D were introduced. These were highly profitable and widely used.

However, it became clear that DDT accumulated in the food chain. This led to its ban in many countries during the 1970s.\n\nManaging how pesticides are used is a major scientific challenge. One major issue is resistance, where pests stop being affected by a substance. Resistance was first observed in the 1920s with inorganic pesticides. To delay this, Integrated Pest Management, or IPM, was introduced in the 1950s. IPM involves analyzing crops and spraying only when a biological or economic threshold of damage is reached.

This method helps maintain natural balances within an ecosystem.\n\nDeveloping new pesticides is a complex and expensive process. Scientists screen various compounds to find \"hits\" or "leads" that work against targets. These leads must be optimized through cycles of synthesis and testing. A new pesticide must be potent, have low toxicity to non-target organisms, and be cost-effective. In 2024, the cost to develop a single pesticide was estimated at 301 million US dollars.

Interestingly, biopesticides are often cheaper to develop because they require less environmental study.\n\nGlobal pesticide use shows significant variations in scale and location. In 2023, the world used 3.73 million tonnes of active ingredients in agriculture. This amount has doubled since 1990. Brazil was the world's largest user in 2023, using 801 kilotonnes.

While application rates per hectare have fallen since the 1950s, total amounts used have increased. In low-income countries, the amount used increased by 1623% between the 1990s and 2010s.\n\nPesticides also have many uses outside of large-scale farming. They are used to control mosquitoes that carry diseases like malaria or West Nile virus. Insecticides can protect animals from parasites like fleas. Herbicides can clear weeds from roadsides or control algae in ponds to keep water pleasant for swimming. They are also used in grocery stores to manage rodents and insects in food storage. Even lawns and golf courses use them for cosmetic reasons.", "media": [ "File:Lite-Trac Crop Sprayer.jpg", "File:Monsanto's Lasso herbicide (cropped).jpg", "File:Pesticide use (2023).svg", "File:Cropduster spraying pesticides.jpg", "File:Pesticide use by region-.svg", "File:Warning2Pesticides.jpg" ] }