ch 22- pesticides

what are pests?

any organism that interferes in some way with human welfare of activities

what are the main pesticide groups?

insecticides, herbicides, fungicides, and rodenticides

What does a narrow spectrum pesticide do?

only kills a specific organism

what does broad spectrum pesticides do?

kills a wide variety of organisms

what characteristics would the ideal pesticide have?

narrow spectrum, easily broken down, and local

what were 1st generation pesticides?

pesticides that were naturally derived compounds (ex: nicotine, pyrethin)

What are the key characteristics of minerals & heavy metals (As, Pb, Hg)?

persistent and highly toxic to humans

What are the key characteristics of botanicals (nicotine, pyrethrin)?

not persistent and highly toxic to aquatic organisms and bees

what were 2nd generation pesticides?

synthetic compounds, often more effective than 1st generation pesticides (ex: DDT)

what are characteristics of chlorinated hydrocarbons (DDT)

persistent, broad spectrum and banned in HDCs

what are the characteristics of organophosphates (malathion)

not persistent, broad-spectrum, most TOXIC, and widely used in agriculture, but not commercially

what are characteristics of carbamates (carbaryl)

NOT persistent, broad spectrum, limited toxicity to birds and mammals, LESS effective than organophosphates

what are selective herbicides?

they only kill certain kinds of plants

What are examples of selective herbicides?

broad-leaf herbicides (2,4-D and 2,4,5-T) and grass herbicides

what are nonselective herbicides?

kill ALL vergettaion

what is an example of nonselective herbicides?

Glyphosate (Roundup)

What is a benefit of pesticides related to disease control?

Fleas, lice, ticks, and mosquitoes carry diseases (e.g., malaria) and pesticides help control these pests.

How much of the world’s crops are destroyed by pests?

Pests eat and destroy 1/3 of the world’s crops.

What is the economic benefit of pesticide use for farmers?

Farmers save $3-5 for every $1 spent on pesticides.

What is an example of a pest that impacts crops, like potatoes in Colorado?

colorado potato bettle

What is a long-term risk of pesticide use?

Resistance buildup in pests

What happens when pests evolve genetic resistance to pesticides?

as long as pesticide application continues, the number of resistant pests increases, and the number of susceptible pests decreases.

How many insect, mite, and plant species have evolved genetic resistance to pesticides after 60 years of pesticide use?

520 insect & mite species and 200 plant species

What is an example of a "superbug" that has evolved resistance to pesticides?

diamondback moths

What are some ways to deal with increased genetic resistance to pesticides?

increase pesticide use (pesticide treadmill) and delay resistance by sacrificing some plants

Where are pesticides commonly found in the environment?

Pesticides are found in most surface waters, 80% of urban streams, and even in Antarctic krill.

How many Americans drink water containing traces of herbicides, and what is the elevated cancer risk in the Midwest?

14 million Americans drink water with herbicides, and 3.5 million in the Midwest face an elevated cancer risk.

What are the effects of short-term exposure to high levels of pesticides?

Harms organs, nervous system, and can be potentially deadly.

What are the effects of long-term exposure to low levels of pesticides?

Sterility, cancers, miscarriage, birth defects, slowed development, and Parkinson’s (confirmed in rats, not humans).

What are some cultivation methods used in sustainable farming?

intercropping, embracing weeds, crop rotation

What is biological control in pest management?

Use of naturally occurring disease organisms, parasites, or predators to control pests.

What is a potential risk of using introduced organisms for biological control

that they can become invasive species, disrupting local ecosystems and harming native species.

How can pheromones be used in pest management?

They can be used as lures for insect traps

What is a method of reproductive control for pests?

Sterilize males with radiation, chemicals, or genetic alteration.

What pest outbreak was controlled using reproductive control in the 90s?

The California medfly outbreak.

What is an example of a genetic control used in agriculture?

Genetically modified/engineered crops, such as Bt crops, which produce a toxin that kills pests.

What are the goals of Integrated Pest Management (IPM)?

Reduce pesticide use, control pest populations, and prevent economic loss.

When are conventional pesticides used in IPM?

Only sparingly and when other methods fail.

what are Persistent organic pollutants (POPs)?

persistent, toxic chemicals that bioaccumulate in orgs & can travel long distances to contaminated areas far from their source

What does the Stockholm Convention on POPs require countries to do?

Develop plans to eliminate the production and use of persistent organic pollutants (POPs).

What is the exception to the Stockholm Convention regarding DDT?

DDT is allowed for malaria control in countries that cannot afford alternative measures.