Latest Event Updates

Beetle Flight Findings May Help Walnut Trees

Posted on Updated on

Findings about the flight patterns of the tiny walnut twig beetle may help prevent a deadly fungal disease in walnut trees. (Kathy Keatley Garvey/UC Davis photo)
Findings about the flight patterns of the tiny walnut twig beetle may help prevent a deadly fungal disease in walnut trees. (Kathy Keatley Garvey/UC Davis photo)

UC Davis entomologist research shows environmental conditions influence behavior of walnut twig beetle.

August 29, 2014
By Pat Bailey
University of California, Davis

New research from entomologists affiliated with the University of California, Davis, shows how environmental conditions influence the seasonal flight behavior of the walnut twig beetle, which spreads a deadly fungal disease in black walnut and other walnut trees. The research may lead to better control of the disease, now found throughout much of the United States.

Yigen Chen and Steve Seybold continually trapped the tiny insect, about a third of the size of a grain of rice, over three years along Putah Creek in Davis, California. They recorded how temperature, light intensity, wind speed and air pressure influenced when the beetles took flight.

“Understanding the walnut twig beetle’s seasonal flight cycle and factors that govern its flight are critical first steps in the early detection of invasive species prior to implementing pest eradication or integrated pest management programs,” said Chen, a research entomologist with the UC Davis Department of Entomology and Nematology. The work appears online in the journal PLOS ONE at: http://bit.ly/1wOyys1.

By itself the tiny walnut twig beetle, Pityophthorus juglandis, does little to walnut trees, said Seybold, who is with the USDA Forest Service Pacific Southwest Research Station in Davis, and is an affiliate of the UC Davis Department of Entomology and Nematology.

However, when coupled with a fungus, Geosmithia morbida, it causes what is known as thousand cankers disease. The beetles create numerous galleries beneath the bark, resulting in fungal infection and canker formation.

The earliest symptom of thousand cankers disease is yellowing foliage that progresses to branch mortality and decline of the tree crown. Other symptoms are numerous small cankers on branches and the trunk, and holes and other evidence of tiny bark beetles.

As the disease advances, the health of the tree declines and eventually it dies, sometimes within a three-year period, said Seybold, who has been studying the beetle and the newly discovered fungus since 2008.

When male beetles initiate new galleries, they produce a pheromone, or scent that attracts other beetles. In earlier work, Seybold and colleagues identified this pheromone and developed a synthetic version that can be used to lure the insects into traps and to disrupt their normal behavior.

Disrupting insect aggregation or mating is crucial to controlling these pests. Understanding how environmental factors affect flight activity should increase the efficacy of integrated pest management methods, Chen said.

The scientists divided the seasonal flight into three phases: emergence, January-March; primary flight, May-July; and secondary fight, September-October. They discovered that more females than males flew in response to the male-produced pheromone. During the spring and summer months (May to September), daily flight patterns showed a minor peak in mid-morning and a major peak at dusk, with about three-fourths of the beetles caught between 6 p.m. and 10 p.m.

New knowledge of when the beetles fly and the effects of weather and lighting should help in deciding when the synthetic pheromones could best be used, the researchers said.

The walnut twig beetle is native to the southwestern United States and Mexico, and has now been detected throughout much of the United States. In 2013, it was reported in northern Italy.

Prions Can Trigger ‘Stuck’ Wine Fermentations

Posted on Updated on

The discovery of biochemical communication system gives scientists a clue to how stuck fermentations can be avoided when making wine.
The discovery of biochemical communication system gives scientists a clue to how stuck fermentations can be avoided when making wine.

UC Davis researchers discovered a biochemical communication system behind this problem.

August 28, 2014
By Pat Bailey
University of California, Davis

A chronic problem in winemaking is “stuck fermentation,” when yeast that should be busily converting grape sugar into alcohol and carbon dioxide prematurely shuts down, leaving the remaining sugar to instead be consumed by bacteria that can spoil the wine.

A team of researchers including UC Davis yeast geneticist Linda Bisson has discovered a biochemical communication system behind this problem.  Working through a prion — an abnormally shaped protein that can reproduce itself — the system enables bacteria in fermenting wine to switch yeast from sugar to other food sources without altering the yeast’s DNA.

“The discovery of this process really gives us a clue to how stuck fermentations can be avoided,” said Bisson, a professor in the Department of Viticulture and Enology. “Our goal now is to find yeast strains that essentially ignore the signal initiated by the bacteria and do not form the prion, but instead power on through the fermentation.”    Read the rest of this entry »

‘One California’ Highlights Agricultural Partnerships

Posted on

From our beginnings as the UC Farm School in 1908, we’ve taught and researched, pioneered and led. And we’ve collaborated with California agriculture for the good of the land and its sustainability.
From our beginnings as the UC Farm School in 1908, we’ve taught and researched, pioneered and led. And we’ve collaborated with California agriculture for the good of the land and its sustainability.

New advertising campaign shows partnerships and agricultural achievements.

August 26, 2014
By UC Davis Dateline Staff
University of California, Davis

One UC Davis” puts the spotlight on California in a new campaign that demonstrates how the university and its industry partners nourish the state with food, economic activity and better health.

In the same way that “One UC Davis” celebrates the uniqueness of everyone connected to the university, “One California” recognizes our food and animal scientists, our students and alumni, farmers and ranchers and processors, and others working in California’s $45-billion-a-year agricultural industry.

Further, the campaign looks to a future of continued innovation, increased productivity and healthier living — by way of UC Davis’ new World Food Center.

“When someone asks, ‘Who will feed the world?’ — the answer is, ‘We will,’” said Roger Beachy, the center’s founding director, ever cognizant of a world population expected to hit 9 billion by 2050.

Who’s we? UC Davis’ top-ranked College of Agricultural and Environmental Sciences, and School of Veterinary Medicine and their partners — the California Poultry Federation, for example. Its president, Bill Mattos, shares the California poultry story every day, including UC Davis’ significant contributions in disease detection and surveillance, among many others. Read the rest of this entry »

Not Quite Water Rights

Posted on Updated on

As the sun sets on this Merced County farm, water is conveyed in an unlined canal to more distant fields. State regulators increasingly are seeking to know how much water is being used throughout the state, and by whom.  (Josh Viers | UC Merced)
As the sun sets on this Merced County farm, water is conveyed in an unlined canal to more distant fields. State regulators increasingly are seeking to know how much water is being used throughout the state, and by whom. (Josh Viers | UC Merced)

California has given away rights to far more water than it actually has.

August 19, 2014
By Kat Kerlin
University of California, Davis

California has allocated five times more surface water than the state actually has, making it hard for regulators to tell whose supplies should be cut during a drought, University of California researchers reported.

The scientists said California’s water-rights regulator, the State Water Resources Control Board, needs a systematic overhaul of policies and procedures to bridge the gaping disparity, but lacks the legislative authority and funding to do so.

Ted Grantham, who explored the state’s water-rights database as a postdoctoral researcher with the UC Davis Center for Watershed Sciences, said the time is ripe for tightening the water-use accounting.

“Given the public’s current attention on drought and California water, we now have an unprecedented opportunity for strengthening the water-rights system,” said Grantham, who conducted the analysis with UC Merced Professor Joshua Viers.

Better information might enable state regulators to better target water cutbacks in times of drought, Grantham said.

Grantham and Viers verified that water-rights allocations exceed the state’s actual surface water supply by about 300 million acre-feet, enough to fill Lake Tahoe about 2.5 times. Read the rest of this entry »

State of the Lake: High (Tech) and Dry at Tahoe

Posted on

A monitoring station at Lake Tahoe, California. The UC Davis Tahoe Environmental Research Center does testing, monitoring, and conservation on the lake. (Photo credit: Gregory Urquiaga | UC Davis)
A monitoring station at Lake Tahoe, California. The UC Davis Tahoe Environmental Research Center does testing, monitoring, and conservation on the lake. (Photo credit: Gregory Urquiaga | UC Davis)

Annual report explains how drought, climate change, and other factors are driving lake changes.

Aug. 14, 2014
By Kat Kerlin
University of California, Davis

Lowering a white disk off a boat and into Lake Tahoe’s blue waters was once the most widely used indicator of the lake’s clarity and health. Today, the Secchi disk is still an important tool, but 46 years after the University of California, Davis, first began continuous monitoring of Lake Tahoe, an array of new technologies and computer models are helping scientists better understand what has proven to be a complex ecosystem.

These complexities are examined in “Tahoe: State of the Lake Report 2014,” released today by the Tahoe Environmental Research Center at UC Davis. The report explains how drought, climate change, and other natural and human factors are driving changes at Lake Tahoe.

The report also describes a new real-time network of about 20 monitoring stations — the first six of which are being installed this month — to explore what is causing degradation to Lake Tahoe’s nearshore environment. In collaboration with public and Read the rest of this entry »

Beer and Beyond: Fermented Foods

Posted on Updated on

Charlie Bamforth, Anheuser-Busch Endowed Professor of Malting and Brewing Sciences at UC Davis
Charlie Bamforth, Anheuser-Busch Endowed Professor of Malting and Brewing Sciences at UC Davis

Charlie Bamforth and former student co-edit a new book on fermented foods.

August 14, 2014
By Robin DeRieux
University of California, Davis

Legendary beer expert Charlie Bamforth, Anheuser-Busch Endowed Professor of Malting and Brewing Sciences at UC Davis, is co-editor of a new book on fermented foods.

The Oxford Handbook of Food Fermentations,” edited by Charles W. Bamforth and Robert E. Ward, is just off the press. Ward, who completed his Ph.D. at UC Davis in 2005, did his master’s degree in food science with Bamforth.

Their book takes a comprehensive look at fermentation, covering food and beverages from bread to beer to brandy, from kefir to kimchee to kombucha. Read the rest of this entry »