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Adult Asian citrus psyllid, Diaphorina citri, (2-3 millimeters long) on a young citrus leaf. Click the image for more information about it.

• Recipe for HLB-affected Citrus: Apply Heat - Lots of It
   
• Fighting Back Against Citrus Greening
   
• Amino Acid Studies May Battle Against Citrus Greening Disease
  

By Dennis O'Brien
August 3, 2016

A U.S. Department of Agriculture (USDA) entomologist is providing citrus growers with much-needed guidance about the best times to use insecticides to control Huanglongbing (HLB), or citrus greening.

HLB has cost Florida citrus growers an estimated $1.3 billion since 2005. The disease is caused by a bacterium spread by the Asian citrus psyllid, which feeds on leaves of infected trees and carries the disease from tree to tree. Insecticides are currently the best option for controlling HLB.

David G. Hall, with Agricultural Research Service's (ARS) U.S. Horticultural Research Laboratory in Fort Pierce, Florida, studied whether trees are more susceptible when producing new leaves-a cyclical phase known as "flush" that happens three or four times a year. Flushing cycles in Florida citrus usually occur in February, in late May, and again in late August. Researchers can prompt new leaf development at almost any time of year by trimming small branches.

Hall and his colleagues trimmed the branches of groups of trees at three staggered intervals. The first group was trimmed three weeks before being exposed to infected psyllids to simulate trees in their "old flush" stage. A second group was trimmed two weeks later to simulate "new flush," and a third group was trimmed two weeks after that to simulate trees that were not in flush. Immediately after the third trimming, the scientists released HLB-infected psyllids and let them feed for a week. The researchers evaluated infection rates after six months.

The results indicate that trees in flush had much higher infection rates than the "no flush" trees, and that the first group of trimmed trees (old flush) experienced the highest infection rates. In one trial, trees exposed to HLB at their old flush stage were 80 percent infected, those exposed during young flush were 23 percent infected, and those with no flush were only 3 percent infected.

The findings show growers the importance of monitoring for psyllids when the trees are in flush, and that it's the older-flush trees they really need to worry about and target with insecticides, Hall says.

Altering the microbes in a very young honey bee's gut can have long-term consequences throughout the bee's life. Click the image for more information about it.

• USDA Scientists and Beekeepers Swap Colonies to Better Bees
   
• Bees Abuzz Over Rapini
   
• USDA Research Identifies Factors for Faster Commercial Honey Bee Queen Failure

By Kim Kaplan
August 2, 2016

WASHINGTON, August 2, 2016—Bacteria in the gut of young honey bees may provide clues about the impact parasites have on bee health. That and other experimental findings were published by U.S. Department of Agriculture's Agricultural Research Service (ARS) researchers in the Proceedings of the National Academy of Sciences.

Because young honey bees don't have gut bacteria, entomologist Jay Evans and post-doc Ryan Schwarz at ARS' Bee Research Laboratory in Beltsville, Maryland, and University of Texas at Austin professor Nancy Moran conducted tests to determine the impact different combinations of a common bacterium and a common parasite had on honey bee health. The scientists hypothesized that increasing the gut bacterium would make the bees more resistant to the parasite, but instead it lead to surprising results.

"This was 180 degrees opposite of our original hypothesis," said Schwarz. "We suspected introduction of the bacterium would promote a resistance to the parasite, but the opposite occurred."

Other findings from the research include,

• If the gut of the young bees were colonized by parasites and/or by an unusually large number of the gut bacterium, they would have a much different gut make-up (microbiome) in later life than normal bees.
• Bees treated with combinations of the bacterium and/or parasites showed greater key detoxification gene activity when placed in a stressed (low-protein diet) condition. This is significant as these genes affect a bee's ability to breakdown foreign molecules, including insecticides.
• Bees with greater parasite infestations might spend more time in the hive as workers and thus increase the likelihood of parasite transmission within the colony and impact the ability of the bees to gather food.

These results highlight how shifts in the bees' gut make-up might play a crucial role in the health of the honey bee colony.

"Bee keepers need to be more mindful of what goes into their hives whether antibiotic, probiotic, or parasite," said ARS entomologist Jay Evans. "Eight types of bacteria usually inhabit a bee's gut. It's clear that more research is needed in order to gain a better understanding of these microbes and their impact on bee health."

Pollinators are critical to the nation's economy, food security and environmental health. Honey bee pollination alone adds more than $15 billion in value to agricultural crops each year and helps ensure that our diets include ample fruits, nuts and vegetables. As part of the National Strategy to Promote the Health of Honey Bees and Other Pollinators, USDA and other federal agencies conduct science-based research to understand and find solutions for the causes of honey bee losses, to increase pollinator habitat and raise awareness about better bee management.

USDA's research and outreach agencies are working in many ways to contribute to the President's National Strategy to Promote the Health of Honeybees and Other Pollinators. For example, the U.S. Forest Service is also conducting research on pollinators while restoring and improving pollinator habitat on national forests and grasslands. Over the past six years, the USDA's Agricultural Research Service has invested more than $82 million in cutting-edge pollinator research and over the past decade has published nearly 200 journal articles about pollinators. USDA's People's Garden Initiative has launched a number of efforts to expand pollinator public education programs, including a bee cam that gives real time insight into the 80,000 bees who live on the roof of USDA's Headquarters and pollinate the surrounding landscape.

The fact sheet: Research and Outreach at USDA Keeps Pollinators Buzzing contains more information about USDA's work to keep pollinators buzzing and contributing to a diverse domestic and global food supply.

The Agricultural Research Service is the U.S. Department of Agriculture's chief scientific in-house research agency. The Agency strives to find solutions to agricultural problems affecting Americans every day. ARS conducts research to develop and transfer solutions to agricultural problems of high national priority and provide information access and dissemination to ensure high-quality, safe food and other agricultural products; assess the nutritional needs of Americans; sustain a competitive agricultural economy; enhance the natural resource base and the environment; and provide economic opportunities for rural citizens, communities, and society as a whole.

Read the magazine story to find out more.

ARS postdoc Erik Landry measures a new winter-hardy faba bean plant while visiting scientist Jun He records the data.

• New Disease Resistant Pea Now Available
   
• USDA Scientists Say Mix-and-Match Cover Cropping Can Optimize Organic Production
   
• New Lentil Being Readied for Market

By Jan Suszkiw
July 27, 2016

Four cold-tolerant faba bean germplasm lines are now available for developing pulse or cover crops that can be rotated with wheat and other cereal grains grown in the Pacific Northwest.

According to the U.S. Department of Agriculture (USDA) scientists who co-developed the new germplasm lines, planting faba beans can offer both environmental and economic benefits. These include converting atmospheric nitrogen into a form subsequent crops can use for growth, forming a thick canopy that shades out weeds, protecting the soil from erosion, and nourishing it when chopped and left to decompose as a so-called “green manure.”

Although current U.S. varieties can tolerate cool temperatures and light frosts, they don’t possess true winter hardiness, according to geneticist Jinguo Hu, with USDA’s Agricultural Research Service (ARS). Shoring up that trait could allow greater flexibility in where and when growers use faba beans as an annual winter cover crop or green manure. Other benefits are fertilizer savings and extra income from harvesting the seed.

In the Palouse—a region encompassing parts of southeastern Washington State and northwestern Idaho—pea, chickpea and lentil are currently used as rotation crops with wheat, the predominant crop there. However, faba bean has the potential to extend the crop diversity in the Palouse and other U.S. regions, notes Hu, who leads ARS’s Plant Germplasm Introduction and Testing Research Unit in Pullman, Washington.

In October 2008, Hu and his ARS and Washington State University collaborators began an intensive screening effort to identify sources of winter hardiness in faba bean plant populations derived from 175 germplasm accessions collected worldwide.

From that total, the team chose several promising lines and produced six consecutive generations of offspring plants to recover and refine the hardiest individuals. They ultimately selected four lines of European descent with average winter survival rates of 84 percent during 2013-2014 field tests in southeastern Washington, where the lowest air temperatures ranged from 11 degrees Fahrenheit (F) down to minus 12.5 F during the past six winter seasons.

Read more about these faba beans in the July 2016 issue of AgResearch magazine. ARS is USDA’s principal intramural scientific research agency.

Agricultural Research Service (ARS) entomologist Patricia Glynn Tillman (center), technician Kristie Graham (right), and student technician Brittany Giles evaluate a sorghum trap crop being used to control stink bugs in adjacent fields of peanuts and cotton. Click the image for more information about it.

• Sniffing Out Overwintering Stink Bugs
   
• USDA Researchers Identify Stink Bug Attractant
   
• Green Alternative for Controlling Native Stink Bugs in the Southeast

By Dennis O'Brien
July 18, 2016

A U.S. Department of Agriculture (USDA) entomologist has found "green" alternatives to insecticides to control three native stink bugs that damage cotton, and the new methods are catching on with growers.

The green stink bug (Chinavia hilaris), southern green stink bug (Nezara viridula), and brown stink bug (Euschistus servus) are a particular problem in the southeastern United States, because cotton is often grown alongside peanuts. Brown and southern green stink bugs develop in peanut fields and migrate into cotton. Green stink bugs move into cotton from nearby wooded areas.

Glynn Tillman, with USDA's Agricultural Research Service (ARS) in Tifton, Georgia, is studying the use of "trap crops," such as soybean and grain sorghum. Trap crops are planted in small strips alongside cotton so that the stink bugs will move into them instead.

Another option is using pheromone-baited traps to capture and kill the bugs. Nectar-producing plants can be grown to attract native parasitoid wasps that attack stink bugs. Placing plastic barriers between cotton and peanut rows is yet another control method.

In a recent study, Tillman and her colleagues grew cotton and peanuts side by side for two years. In the first year, they planted soybeans as a trap crop, with and without pheromone traps, between the cotton and peanut rows. In other areas, they placed 6-foot-high plastic barriers between the rows. In the second year of the study, they added nectar-producing buckwheat plants near the cotton. Each week during the May-to-October growing season, they counted the stink bugs and stink bug eggs killed by wasps, and documented the damage to cotton bolls.

They found that physical barriers between peanut and cotton were the most effective tool and that the multi-pronged approach is an effective alternative if barriers are not feasible. They also found that soybeans were an effective trap crop and that buckwheat plants attracted beneficial wasps that reduced stink bug numbers.

Read more about this research in the July 2016 issue of AgResearch.

ARS is USDA's principal intramural scientific research agency.

Kudzu completely engulfs this Mississippi landscape and robs it of its value. Click the image for more information about it.

• Egg Cage System May Bolster Native Ladybug's Biocontrol Prospects
   
• Researchers Study Fire Ant Venom as Natural Fungicide
   
• Biocontrol Agent Tested to Battle Invasive Kudzu Bug

By Sandra Avant
July 13, 2016

According to a U.S. Department of Agriculture (USDA) study, the use of combined management programs can control kudzu more quickly than individual methods in use today.

An invasive weed, kudzu was introduced to the United States in the late 1800s. It disrupts native ecosystems, threatens natural resources, and inhibits use of forest land, particularly in Mississippi, where kudzu is pervasive. Land infested with kudzu has little or no value.

Agricultural Research Service (ARS) scientists in Stoneville, Mississippi, reviewed different programs known to successfully suppress kudzu. Mark A. Weaver, a plant pathologist in the ARS Biological Control of Pests Research Unit, and his team used a combination of these programs, including a herbicide-free "organic" system, to achieve a high rate of kudzu suppression and eradication.

Typically, it takes about 10 years of persistent herbicide applications to eradicate kudzu. Weaver developed a series of effective management programs that can substantially reduce kudzu over one- and two-year periods.

Once landowners remove kudzu, they can use their land productively, according to Weaver. They can establish forestry, wildlife habitats and recreational parks.

Weaver applied four different herbicides, individually or in combination, and a bioherbicide treatment at three different kudzu-infested sites. (A bioherbicide is a biologically based control agent for weeds.) He repeated these treatments for two years. Results showed a high level of suppression on the small plots after just one year. An even higher percentage of kudzu—99 to 100 percent—was killed during the second year.

The organic treatment, which simultaneously established native vegetation, killed 91 percent of kudzu after one year and 95 percent after two years. The treatment involves applying a bioherbicide application, mowing and revegetation.

ARS is USDA's principal intramural scientific research agency.

Read more about this research in the July 2016 issue of AgResearch magazine.

Cross section of cocoa beans in a cacao pod. Click the image for more information about it.

• Cacao Collection Expedition May Yield Weapons for Combating Witches' Broom Disease
   
• Sequencing the Cacao Genome to Safeguard Chocolate
  

By Jan Suszkiw
July 6, 2016

U.S. Department of Agriculture (USDA) scientists have sequenced the frosty pod rot fungus genome. That advance could speed the development of cacao tree varieties that better withstand this costly blight.

The fungus that causes frosty pod rot disease, Moniliophthora roreri, occurs in most cacao-growing countries of Central and South America. Unchecked, the disease can destroy as much as 90 percent of the beans from which cocoa, cocoa butter, and ultimately chocolate are made.

Growers use an integrated approach to control frosty pod rot by planting cacao tree cultivars that tolerate the disease. However, the fungus has shown signs of changing tactics, a worrisome development for producers and consumers alike. During the past 15 years, losses to frosty pod rot have slowly increased for varieties once considered disease tolerant, notes Bryan Bailey, a plant pathologist with Agricultural Research Service's (ARS) Sustainable Perennial Crops Laboratory in Beltsville, Maryland.

Sequencing the fungus's genome has enabled researchers to observe its biotrophic (surviving on living tissue) and necrotrophic (surviving on dead tissue) phases, as well as learn how the pathogen survives in cacao plants considered tolerant to infection. For example, one theory suggests the fungus is changing genetically enabling a rapid shift from a biotrophic to necrotrophic state.

The research team's investigations included genetic sleuthing tracing the fungus to the upper Magdalena Valley of Colombia.

That discovery—reported in the August 2015 issue of Frontiers in Microbiology—has identified a location where researchers can search for cacao trees that are disease tolerant or resistant. Plant breeders could then transfer those newly identified genes into currently grown cultivars, notes Bailey.

ARS is USDA's principal intramural scientific research agency.

Read more about this research in the July 2016 issue of AgResearch.

ARS molecular biologist Doug Hinchliffe (left) and ARS textile technologist Michael Reynolds inspect nonwoven fabric for use in cotton-based wipes. Click the image for more information about it.

• Assessing Cotton Fiber Quality from a Tiny Sample
   
• New Treatments Could Reduce Odors in Cotton Fabric
   
• Cotton's Potential for Padding Nonwovens

By Rosalie Marion Bliss
June 27, 2016

People concerned about the environmental impact of synthetic disposable wipes accumulating in landfills can now take comfort in U.S. Department of Agriculture (USDA) scientists' progress in developing disinfecting wipes made from nonwoven cotton that are biodegradable.

Disposable disinfecting wipes made from synthetic fibers are effective and convenient. They are soaked in a solution that contains germ-killing compounds called "quats." These compounds release readily from synthetic fibers, allowing the wipes to disinfect properly. Unfortunately, synthetic fibers decompose slowly in landfills. Cotton fibers, while biodegradable and thus better for the environment, do not readily release the germicide.

That soon could change.

Agricultural Research Service (ARS) scientists have discovered new chemical formulations that allow quats to release readily from nonwoven cotton fibers, resulting in hospital-grade disinfecting cotton wipes that are both effective and biodegradable.

Research leader Brian Condon, molecular biologist Doug Hinchliffe, and colleagues in the ARS Cotton Chemistry and Utilization Research Unit in New Orleans, Louisiana, worked on the project with Cotton Incorporated.

The ARS team tested a quat called "ADBAC," a stable, cost-effective active ingredient in synthetic disposable disinfecting wipes particularly effective on hard surfaces. The quat adhered so strongly to the surface of cotton fibers that it failed to release in amounts sufficient to disinfect hard surfaces.

The ARS team developed new chemical formulas that block quats from adhering strongly to the surface of cotton fibers. The result is a cotton wipe that releases quats for surface disinfection that is strong, abrasive and fully biodegradable.

In the study, the cotton wipe containing the new ADBAC formula killed four microorganisms of great concern in healthcare environments, including MRSA (methicillin-resistant Staphylococcus aureus) and VRE (vancomycin-resistant Enterococcus), which are of particular concern in hospitals.

Research partner Cotton Incorporated will be marketing this technology. Adopters of the new technology will conduct further testing to broaden the list of microorganisms the wipes can disinfect.

Read more about this research in the June 2016 issue of AgResearch.

ARS is USDA's chief intramural scientific research agency.

The ARS Honey Bee Breeding, Genetics and Physiology Lab and the Louisiana Armed Forces Foundation are teaching beekeeping to veterans. Click the image for more information about it.

By Kim Kaplan
June 23, 2016

BATON ROUGE, LOUISIANA, June 23—Honey bees may reduce stress and become a new business venture for those who have served in the U.S. military. That premise guides a unique partnership between the Honey Bee Breeding, Genetics and Physiology Laboratory and the Louisiana Armed Forces Foundation (LaAFF).

The lab, part of the U.S. Department of Agriculture's Agricultural Research Service (USDA-ARS), and LaAFF are hosting a June 25 workshop in Baton Rouge to introduce veterans to beekeeping.

"We want to give back to the veteran community," explained ARS researcher Michael Simone-Finstrom. "We do that by helping veterans, both new and experienced at beekeeping, learn about honey bee biology including their pests and pathogens. Then we provide hands-on experience with sustainable honey bees our lab has developed so they can raise healthy bees from the start."

This coaching builds a strong foundation for maintaining healthy colonies, and adding more healthy managed honey bees to the environment which helps all beekeepers, added Simone-Finstrom.

While honey bees may sound like an odd stress reliever for veterans, beekeeping really interests veterans, according to LaAFF cofounder Jaye Townsend.

"People regularly say that working with honey bees is therapeutic and has potential as a business opportunity. So, we met with ARS scientists, decided to hold an open house and found lots of interest in connecting veterans with bees," Townsend said.

Veterans with a wide variety of bee experience are participating in the workshop. One of the more experienced is U.S. Army veteran C.J. Oliver, whose family produces about 60 gallons of honey annually in Arnaudville, Louisiana.

"We (my family) see this workshop as a good learning experience as we've gone from hobby to secondary income to hopefully a full-time business one day," Olivier said.

ARS' Honey Bee Breeding, Genetics and Physiology Laboratory is the developer of elite honey bee strains - including bees from Russia, where factors like prolonged winters allow only the sturdiest bees to survive. Today, the Baton Rouge lab is focused on breeding for better resistance to diseases and pests that pose major problems for honey bees.

The Agricultural Research Service is the U.S. Department of Agriculture's chief scientific in-house research agency. The Agency's job is finding solutions to agricultural problems that affect Americans every day from field to table. ARS conducts research to develop and transfer solutions to agricultural problems of high national priority and provide information access and dissemination to ensure high-quality, safe food, and other agricultural products; assess the nutritional needs of Americans; sustain a competitive agricultural economy; enhance the natural resource base and the environment and provide economic opportunities for rural citizens, communities, and society as a whole.

ARS entomologist James Strange evaluates a queen bumble bee (Bombus appositus) during a search for new wild bees with potential to become the next generation of agricultural pollinators. Click the image for more information about it.

• The Flight of the Bumble Bee: Why Are They Disappearing? 

• Bee Pastures May Help Pollinators Prosper
   
• Bumblebee ID Simplified With Wallet Card

By Jan Suszkiw
June 23, 2016

Look up the word “bumble,” and the definition may read something like “To move or act in a confused, awkward or clumsy manner.” But the bumble bee, a member of the genus Bombus, is anything but clumsy. In fact, the insects are expert aviators, alighting with precision inside flowers and vigorously shaking pollen loose from their stamens.

Some bumble bee species are pollinating professionals on par with honey bees. At the Agricultural Research Service’s (ARS) Pollinating Insect-Biology, Management, Systematics Research Unit in Logan, Utah, scientists are conducting multi-faceted studies on Bombus species of all shapes, sizes and colors to ensure their wellbeing and usefulness to agriculture—especially in pollinating greenhouse-grown plants, primarily tomatoes.

One project, the USBombus database, actually arose out of concern over the national decline of four Bombus species—including the western bumble bee, Bombus occidentalis, which had been reared commercially up until the early 2000s, notes James Strange, an ARS entomologist in Logan.

USBombus—the largest database of a contemporary North American bumble bee survey—was created in 2010, following a three-year effort by Strange and other ARS and university scientists to assess the abundance and distribution of wild Bombus populations across a wide range of habitats. These included urban, agricultural and natural environments, such as alpine forests and prairies.

Housed at the Logan lab as part of the U.S. National Pollinating Insects Collection, the database originally stored information on 17,930 adult bumble bee specimens collected from 41 states and representing 39 total Bombus species. That number has expanded to over 80,000 specimens and counting, as more historic and current collections are added, notes Strange.

Some of the latest specimens include a few he collected and identified this past May while he was participating in Centennial Bioblitz events hosted by the U.S. National Park Service at the North Cascades and Olympic national parks in Washington State.

The data—which include the bee specimens’ species name, sex, caste, location, collector, preferred plants and other information—have proven useful on several fronts, including taxonomic studies and monitoring of Bombus populations to ascertain their health and “conservation status” by groups such as the International Union for the Conservation of Nature. (“Conservation status” refers to the likelihood of a species’ future survival in the face of habitat loss, disease and other threats.)

USBombus and the National Pollinating Insect Database, which includes specimens dating back to the 1800s, can be accessed on the Internet via the Global Biodiversity Information Facility website at http://www.gbif.org/.

Close-up of Varroa mites in the bottom of a brood cell—home to vulnerable bee larvae. Click the image for more information about it.

• Bees Abuzz Over Rapini
   
• New ARS Bee Genebank Will Preserve Genetic Diversity and Provide Breeding Resources
   
• Bee Survey: Lower Winter Losses, Higher Summer Losses, Increased Total Annual Losses

By Jan Suszkiw
June 22, 2016

U.S. Department of Agriculture (USDA) scientists are hot on the trail of a honey bee killer, and their detective work has taken them from hives in Tucson, Arizona, to those in Bismarck, North Dakota.

Led by Agricultural Research Service (ARS) supervisory research entomologist Gloria DeGrandi-Hoffman, the team is staking out the entrances of victimized hives, eyeing the comings and goings of foraging honey bees that they suspect may be unwitting accomplices.

Instead of cordoning off the sites with crime-scene tape, the scientists are blocking access to the hives using cut lengths of PVC pipe with a slit about midway down. There, a sliding wire-mesh door separates incoming bees from outgoing ones.

None of the busy little winged bearers of pollen and nectar will get by without inspection-and for good reason: the researchers suspect the bees are physically harboring their target: an oval-shaped, pinhead-sized parasite called the Varroa mite.

The Varroa mite is public enemy number one to not only honey bees nationwide, but also the 90-plus flowering crops that depend on the insects to pollinate them, including apples, almonds, blueberries and cantaloupe.

The team's investigations in Bismarck this June are actually a follow-up study to the one they completed last year at two Arizona sites. Findings from that study suggest that bees can bolster their hives' existing mite population by carrying in Varroas from other colonies-an influx that most often occurs in the fall, especially November.

Varroa populations grow slowly because females produce only three to five offspring. If mite populations in colonies are low, then they should remain that way for at least a season before chemicals called "miticides" need to be applied, explains DeGrandi-Hoffman, who leads ARS's Carl Hayden Bee Research Center in Tucson.

Sometimes, though, Varroa numbers soar to potentially hive-wrecking levels during the fall. To the researchers, this suggested that factors other than mite reproduction were involved-namely, "mite migration" via foraging bees and wayward "drifters" from other colonies. At the Arizona hive sites, this influx of migrating mites correlated to population increases of 227 to 336 percent, starting in November. The findings appeared in the February 2016 issue of Experimental and Applied Acarology.

In addition to further investigation at a Bismarck apiary, the researchers will also evaluate placing hives in refrigerated storage in the fall to head off mite migration into colonies. They'll determine the strategy's effectiveness based on whether it reduces the need for miticide applications, keeps Varroa populations low and results in high winter survival rates for colony members.

ARS is USDA's principal intramural scientific research agency.

ARS Bee Research Lab insect physiologist Miguel Corona (left) and Geezer Ridge Farm beekeeper Ed Forney in the midst of swapping of boxes of honey bees in a new partnership aimed at improving colony losses. Click the image for more information about it.

By Kim Kaplan
June 21, 2016

BELTSVILLE, Md., June 21, 2016 —The U.S. Department of Agriculture's (USDA) Agricultural Research Service (ARS) Bee Research Laboratory and Geezer Ridge Farm apiary have begun an unusual partnership that may help honey bees take another step up the survival ladder.

"Usually with science, researchers finish a study and turn the results over to beekeepers to apply; then researchers start on the next experiments and so on," explains entomologist Jay Evans, research leader of the Beltsville, Maryland lab and one of the USDA's pioneers in bee health science.

This time, the Bee Research Lab is studying the success Geezer Ridge Farm in Hedgesville, West Virginia, has had improving honey bee health after applying USDA research results.

Last winter, beekeepers Cheryl and Ed Forney lost only 4 percent of their bee colonies compared to the national average of 30 percent.

"We believe strongly in science-based beekeeping. It's the Bee Research Lab—some of the most talented and published researchers in the country—that helped us get our colonies as healthy as they are now. From their (ARS') information, we've adapted management strategies and bred bees that are tailored to the Mid-Atlantic's climate," Ed Forney said.

To see if this success is scientifically repeatable, Geezer Ridge Farm and the ARS Bee Research Lab are exchanging colonies. Forty USDA hives have already taken up residence in West Virginia and another 80 may join them to see if they will survive the 2016-2017 winter in better condition under Geezer Ridge Farm management.

"This is an opportunity to give back. We are going to see if we can stabilize the USDA research colonies and make them as sustainable as the stock here at Geezer Ridge Farm," Forney added.

Thirty-five of Forney's 250 colonies have come to Beltsville where ARS researchers will study their basic biology and genetics to see if they differ from the average honey bee. In the process, they'll try to pinpoint whether their increased survival is due to better genetics, better management, or both.

Three ARS Bee Research Lab scientists are involved in the partnership with Geezer Ridge Farm. Each focuses on a different research area addressing threats to bee health. Insect physiologist Miguel Corona, who initiated this collaboration, focuses on bee nutrition such as devising new ways to deliver more protein in honey bee diets. Entomologist Steven Cook is studying how to improve honey bees' physiological health as well as their abilities to overcome stress. Lastly, Jay Evans's work concentrates on researching and combating bee disease.

The Agricultural Research Service is the U.S. Department of Agriculture's chief scientific in-house research agency. The Agency's job is finding solutions to agricultural problems that affect Americans every day from field to table. ARS conducts research to develop and transfer solutions to agricultural problems of high national priority and provide information access and dissemination to ensure high-quality, safe food, and other agricultural products; assess the nutritional needs of Americans; sustain a competitive agricultural economy; enhance the natural resource base and the environment and provide economic opportunities for rural citizens, communities, and society as a whole.

Read the magazine story to find out more.

Finger millet uses less water than corn and sorghum and could be a good source of cattle feed.

• USDA Scientist Helps Texas Sorghum Growers Reduce Water Use
   
• Two Approaches for Optimizing Water Productivity
   
• USDA Irrigation Research: Good to the Last Drop

By Dennis O’Brien
June 6, 2016

U.S. Department of Agriculture (USDA) scientists are trying to save water in one of the fastest growing dairy regions in the United States by encouraging use of a drought-tolerant crop the same way it’s sometimes used in India—as cattle feed.

Dairy production is growing fast in the Southern High Plains region of West Texas and New Mexico, and most of the dairy producers there use corn silage or alfalfa as a key feed component. Corn and alfalfa require more water than other crops, thus stretching the Ogallala Aquifer, the source of water for that region, beyond capacity.

Prasanna Gowda, an Agricultural Research Service (ARS) engineer, knew that dairy cattle in his native India are raised on finger millet (Eleusine coracana) and that milk from finger millet-fed cows there sells for a higher price.

As part of their research, Gowda and his colleagues grew five finger millet varieties in Bushland for 120 days, selecting plants of each variety based on crude protein, fiber content, and other nutritional qualities. They compared the finger millet’s nutritional qualities to those of corn and sorghum from neighboring plots.

Gowda found that finger millet had higher levels of potassium than corn, twice as much calcium, four to five times as much phosphorus, and comparable levels of protein, fiber and total digestible nutrients. (Calcium and phosphorus deficiencies reduce dairy cattle’s appetites and growth and lower milk production.) Finger millet also used less water than corn and sorghum. The one drawback was that finger millet produced lower yields than corn.

The results showed that finger millet could be a viable feed source for dairy cattle as a supplement to corn and that it could help save water in areas where water is limited, Gowda says.

Gowda was based in Bushland, Texas at the time of the study, but has since moved to the ARS Grazinglands Research Laboratory in El Reno, Oklahoma.

ARS is USDA’s principal intramural scientific research agency. Read more about this research in the June 2016 issue of AgResearch magazine.

Read the magazine story to find out more.

An acoustic trap that lures and captures male Asian citrus psyllids may help protect citrus trees from Huanglongbing disease, which is transmitted by the pest. View related video.

• Recipe for HLB-affected Citrus: Apply Heat—Lots of It
   
• Fighting Back Against Citrus Greening
   
• Amino Acid Studies May Aid Battle Against Citrus Greening Disease

By Jan Suszkiw
May 31, 2016

An acoustic trap developed by U.S. Department of Agriculture (USDA) scientists may offer an environmentally friendly way to control Asian citrus psyllids, gnat-sized insect pests that transmit Huanglongbing, a devastating citrus disease also known as “citrus greening.”

Infected citrus trees cannot be cured and often die within several years. Until such time, they may bear green, misshapen fruit with acidic-tasting juice, making the fruit unmarketable.

Concern over the cost and long-term environmental impact of using insecticides to control psyllid populations in citrus-growing states like Florida has prompted an intensive search for alternative measures, notes Richard Mankin, an entomologist with USDA’s Agricultural Research Service (ARS) in Gainesville, Florida.

To that end, Mankin designed an acoustic trap based on his experience investigating how insect pests use their sense of smell, sight or hearing to locate food and mates. Together with University of Florida graduate students, Mankin decoded the psyllid’s signaling patterns and recreated them with electronics including a buzzer and a microphone.

Many of the traps now used to control crop-damaging insects use chemical attractants, or “pheromones.” Low doses of pheromones can lure pests into traps; high doses can saturate the air so thickly that pests fail to meet and mate. The acoustic trap is different: It mimics the wing-buzzing vibrations male and female psyllids use instead of pheromones to locate and court one another in citrus trees.

In citrus trees, a male psyllid normally crawls to the female after the female responds to the male’s wing-buzzing vibrations. In laboratory studies, however, the trap is also listening to this vibration, and it responds a tenth of a second or two before the female with a fake signal, luring the males into a nearby sticky trap.

Mankin’s team is refining the trap for outdoor testing this summer. Read more about this research in the May 2016 issue of AgResearch magazine.

Read the magazine story to find out more.

The tiny wasp Tetrastichus planipennisi is an effective biocontrol for the emerald ash borer, an ash tree pest.

• Scientists Exploit Ash Tree Pest's Chemical Communication
   
• Developing Biocontrols to Contain a Voracious Pest
   
• ARS Scientists Cryopreserve Pest-Imperiled Ash Trees

By Sharon Durham
May 25, 2016

A wispy wasp may pack a potent punch in the fight against the emerald ash borer (EAB), an insect pest that causes catastrophic ash tree losses in the United States.

EAB has wings that are deep emerald green on the outer edge and a body underneath that’s iridescent magenta. Its stunning appearance belies the fact that it is a deadly, non-native pest that has killed tens of millions of ash trees in North America since its detection in 2002 in Detroit, Michigan, and Ontario, Canada.

The cost of EAB damage is staggering. According to U.S. Forest Service estimates, responses to EAB infestation between 2009 and 2019—including treatment, removal, and replacement of more than 17 million ash trees—could total $10.7 billion.

U.S. Department of Agriculture (USDA) scientists, along with collaborators at the University of Massachusetts, found a tiny titan—Tetrastichus planipennisi—that can reduce EAB population growth by a whopping 90 percent.

A recent 7-year field study conducted by scientists from the Agricultural Research Service (Jian Duan), the Forest Service (Leah Bauer and Mike Ulyshen), and the University of Massachusetts (Roy van Driesche and Kris Abell) showed that the T. planipennisi released between 2007 and 2010 in central Michigan spread quickly and contributed to a significant reduction in EAB population growth. T. planipennisi parasitizes EAB larvae by drilling through the bark and laying eggs on its host.

The research team observed a 90-percent decline in live EAB larvae in infested ash trees at both parasitoid-release plots and control plots. According to Duan, 7 years’ worth of field data demonstrated that the decline in EAB larvae was correlated with significant increases in EAB larval parasitism, first by native parasitoids, then by T. planipennisi. The study was recently published in the Journal of Applied Ecology.

Read more about this research in the May 2016 issue of AgResearch.

Read the magazine story to find out more.


Tomatoes kept at room temperature will release more flavor compounds when cut up than will refrigerated tomatoes.

• Recipe for Flavorful Tomatoes: Heat Before Chilling
  

• Fighting Back Against Citrus Greening
  

• The Search for What Makes a Tasty Tomato
  
  

By Dennis O’Brien
May 12, 2016

Two Agricultural Research Service (ARS) scientists in Fort Pierce, Florida, have taken different approaches to enhancing the flavor of tomatoes.

ARS plant physiologist Jinhe Bai and his colleagues at the U.S. Horticulture Research Laboratory studied the effects of refrigerating tomatoes and dipping them in hot water to make them easier to peel—a practice known as “blanching.”

Bai and his colleagues divided 60 tomatoes into three groups—refrigerating one group, keeping a second group at room temperature and dipping the third group in 122 F water for 5 minutes to simulate blanching. They then used gas chromatography and an “electronic nose” to measure 45 volatile compounds associated with flavor released when the tomatoes were cut up.

The results showed that refrigeration greatly reduced 25 of 42 aroma compounds and reduced volatile levels overall by 68 percent. Blanching also greatly reduced 22 of 42 compounds and reduced volatile levels overall by 63 percent. The results spell out why it is better to store tomatoes—and wash them before use—at room temperature.

Elizabeth Baldwin, an ARS horticulturist and research leader in Fort Pierce, wanted to find tomato breeders interested in developing varieties with enhanced flavor. She also wanted to identify varieties and growing seasons best suited to two of Florida’s major tomato production areas.

She and her colleagues raised 38 types of tomatoes over seven years in south Florida and west-central Florida, timing production for harvest in March, June and December.

They used human taste-test panels to evaluate flavor and measured the tomatoes’ sugars, acids and 29 key aroma compounds.

The results showed that the tomatoes needed to contain a certain amount of acids to have adequate flavor and that the more sugar they contained, the better they tasted. Tomatoes harvested in June had more sugar and fruity volatiles than those harvested in December, probably because they received more sunshine. Tomatoes harvested in March ranked in the middle in flavor.

Read more about tomato flavor research in the May 2016 issue of AgResearch.

ARS is USDA’s chief intramural scientific research agency.