User:Cjohnsonhall/sandbox

Pest Insects and Climate Change

Global warming is likely to lead to an increase in pest insect populations, harming yields of staple crops like wheat, soybeans, and corn. While warmer temperatures create longer growing seasons, and faster growth rates for plants, it also increases the metabolic rate and number of breeding cycles of insect populations. Insects that previously had only two breeding cycles per year could gain an additional cycle if warm growing seasons extend, causing a population boom. Temperate places and higher latitudes are more likely to experience a dramatic effect in insect populations

The University of Illinois conducted studies to measure the effect of warmer temperatures on soybean plant growth and Japanese beetle populations. Warmer temperatures and elevated CO₂ levels were simulated for one field of soybeans, while the other was left as a control. These studies found that the soybeans with elevated CO₂ levels grew much faster and had higher yields, but attracted Japanese beetles at a significantly higher rate than the control field. The beetles in the field with increased CO₂ also laid more eggs on the soybean plants and had longer lifespans, indicating the possibility of a rapidly expanding population. DeLucia projected that if the project were to continue, the field with elevated CO₂ levels would eventually show lower yields than that of the control field.

The increased CO₂ levels deactivated three genes within the soybean plant that normally create chemical defenses against pest insects. One of these defenses is a protein that blocks digestion of the soy leaves in insects. Since this gene was deactivated, the beetles were able to digest a much higher amount of plant matter than the beetles in the control field. This led to the observed longer lifespans and higher egg laying rates in the experimental field.

There are a few proposed solutions to the issue of expanding pest populations. One proposed solution is to increase the number of pesticides used on future crops. This has the benefit of being relatively cost effective and simple, but may be ineffective. Many pest insects have been building up an immunity to these pesticides. Another proposed solution is to utilize biological control agents. This includes things like planting rows of native vegetation in between rows of crops. This solution is beneficial in its overall environmental impact. Not only are more native plants getting planted, but pest insects are no longer building up an immunity to pesticides. However, planting additional native plants requires more room, which destroys additional acres of public land. The cost is also much higher than simply using pesticides

Some future sources:

1. http://www.livescience.com/4296-global-warming-trigger-insect-population-boom.html

2. http://www.ucsusa.org/global_warming/science_and_impacts/impacts/Global-warming-insects.html#.WOwzzDvytPY

3. http://www.els.net/WileyCDA/ElsArticle/refId-a0022555.html

4. https://www.fs.usda.gov/ccrc/topics/insect-disturbance-and-climate-change

5. http://www.scielo.br/scielo.php?

Peer review

• Wentao: Overall I really think you successfully expanded the article. But just a side note that you can probably do some research on, is that does the rate at which pest insect population is growing related to the dimensions of their body? Certain insects are definitely bigger, some are smaller. Do they all share the same growing rate or they have different growing rates? Also maybe a couple more research examples will further expand this article.
• Deleted [null.].
• Subscripted the CO2
• Suggestion: insert Wikilinks for concepts that have a Wikipage, like "University of Illinois" (which one?), "Japanese Beetle", "soybean", "corn", etc.
• I think this is already very good, and I agree that you could just add more Wikilinks as stated above^