In the National News
Sounds Identify Drought
At the spring 2013 American Physical Society conference, physicists at Grenoble University in France reported their findings on ultrasonic sounds made by trees under drought stress. Pressure inside trees that lack water builds within xylem cells, sometimes leading to the formation of air bubbles that block the flow of water, called cavitations. Trees can withstand some cavitations, but too many can be deadly. These cavitations can be heard with a microphone, but no one has ever been able to distinguish a cavitation from general creaking until now. The scientists conducted a lab study mimicking a drought-stressed tree, and were able to assign a distinct sound wave to cavitations. The findings could lead to the design of a device that would attach to a tree and constantly listen for sounds of “thirst.” If needed, the device could then trigger an emergency-watering system.
Beetles Subvert Defenses
Plants may defend themselves from insect feeding by producing chemicals within plant tissues that interfere with the insects’ digestion and growth. Entomologists at Penn State University have been studying the Colorado potato beetle, and found that sometimes, feeding by the beetle “turns off” the plant defense response, allowing the beetles to be healthy and productive. They reported in the Proceedings of the National Academy of Sciences that 3 species of bacteria living in the beetle’s gut are able to suppress the plant’s anti-herbivore response. The researchers will next determine if these bacteria are present in Colorado potato beetles all over the U.S. and in Europe.
New Biocontrol May Help Monarchs
Swallow-wort is an aggressive invasive weed that forms dense patches in a wide variety of habitats in eastern North America, and may have negative impacts on monarch butterfly populations. Monarchs readily lay eggs on the milkweed-relative, but the hatched larvae do not survive. In 2006, a University of Rhode Island graduate student discovered a moth pest of swallow-wort in southern Ukraine, and for the past 7 years, he and colleagues have conducted a rigorous study of its biology and host range, and petitioned the USDA and the Canadian government for its use as a biological agent. The moth only feeds on swallow-wort, and the first release of 500 larvae occurred in Canada in early fall 2013.
A Venomous Insecticide
The venom from tarantulas is now being considered as a biopesticide. In a paper published in PLOS ONE, researchers from the University of Queensland, Australia, found that venom extracted from Australian tarantulas was found to be as deadly to termites and cotton bollworms as the common pesticide, imidacloprid. Scientists say that venom from insect-eaters like centipedes and scorpions may also be used as biopesticides in the future, or perhaps may even help breeding plants to resist insects.
Climate Change Aids in Pest Distribution
Researchers at the Universities of Exeter and Oxford have seen a strong correlation between the geographical spread of crop pests and recent climate changes. A new study appearing in the journal Nature Climate Change compared published distributions of 612 crop pests collected over the past 50 years. The results suggest that the warming climate has allowed a variety of pests to spread toward the North and South Poles at almost two miles a year. Currently, 10-16% of global crop production is lost due to pests, and losses are predicted to increase with continued warming.
Stink Bugs Spreading in California
California Department of Food and Agriculture reported that brown marmorated stink bug has become established in Sacramento, making it the first new location in California outside of Los Angeles. This insect is classified by the state as a Class B pest – a detriment to the economy and environment, yet limited in distribution. Because of this distinction, the state has not funded an eradication program.
Grapefruit May Triumph Over Pests
Nootkatone, a component of grapefruit oil, has been used for years in fruit-flavored juices and perfumes. In the past, scientists at the U.S. Centers for Disease Control and Prevention showed that it safely and effectively controls ticks, mosquitoes, and other insects, but until now, it was too expensive to manufacture as a biopesticide. The renewable chemical company, Allylix, recently developed a proprietary protocol to develop nootkatone, making it possible to develop nootkatone biopesticides.
Useful Publications and Apps
• Stopbmsb.org has posted a list of 170 host plants for brown marmorated stink bug. The site includes distribution maps, educational info, and monitoring and identification videos.
• Check out the videos available from UC Davis on mosquitoes, bedbugs, ants, pesticides, and more.
• Uncommonfruit is a new website out of Wisconsin highlighting research trials of new and unusual fruit.
Calendar of Events
November 4 - 5, Ninth Continental Dialogue on Non-Native Forest Insects and Diseases, Pittsburgh, PA, www.continentalforestdialogue.org
November 10 - 13, Entomological Society of America's 61st Annual Meeting - "Science Impacting a Connected World", Austin, TX, www.entsoc.org/entomology2013
November 13, Southern Utah Green Conference, Washington, UT, www.utahgreen.org/events
December 3 - 5, 4th International Phytophthora capsici Meeting, Duck Key, FL, reg.conferences.dce.ufl.edu/PCAP
December 5 - 6, Global Bed Bug Summit, Denver, CO, www.bedbugcentral.com/events/npma-global-bed-bug-summit-2013
January 8 - 9, Orchard Pest and Disease Management Conference, www.tfrec.wsu.edu/pages/wopdmc
January 21 - 23, Utah State Horticultural Association Annual Convention, Spanish Fork, UT, www.utahhort.org
January 27 - 29, Lawn Care Summit 2014, Nashville, TN, www.landcarenetwork.org/events
January 27 - 29, Utah Nursery and Landscape Association Green Conference, Sandy, UT, www.utahgreen.org/events