But thrips do pack a powerful punch.
A major pest of many agricultural crops, including lettuce, they damage plants by (1) sucking their juices and (2) transmitting viruses.
If you've been following the thrips damage in the lettuce production in the Salinas Valley, or want to know more about thrips, the UC Davis Department of Entomology and Nematology's virtual seminar on Wednesday, Jan. 20 should interest you.
Research entomologist Daniel Hasegawa of the Crop Improvement and Protection Research Unit, Agricultural Research Service, U. S. Department of Agriculture, will speak on "Landscape and Molecular Approaches for Managing Thrips and Thrips-Transmitted Viruses in the Salinas Valley" at the department's first seminar of the winter quarter.
The hour-long virtual seminar, via Zoom, begins at 4:10 p.m., announced agricultural Extension specialist Ian Grettenberger, seminar coordinator. To access the seminar, fill out this Google form link at https://bit.ly/3oWYjnt. (Contact Grettenberger at firstname.lastname@example.org.)
"In 2019-2020, lettuce production in the Salinas Valley of California was devastated by thrips-transmitted impatiens necrotic spot virus (INSV)," Hasegawa says in his abstract. "Due to the inherent challenges in managing thrips using conventional chemical tactics, and no direct means for managing the virus, there is a strong need for new management strategies."
This seminar, he says, will provide an overview of
- The challenges in managing thrips and INSV in lettuce production
- What we've learned about the epidemiology of thrips and INSV, and
- Opportunities to improve cultural practices and develop biotechnology tools, such as RNAi for managing thrips and INSV in the Salinas Valley.
Hasegawa joined the Salinas USDA-ARS team in May 2019 after serving as a postdoctoral research associate (molecular biology) for three years with the USDA-ARS in Charleston, S. C. He specializes in vector entomology, molecular biology and biotechnlogy. "My lab uses a variety of techniques to understand insect vector-virus relationships that impact plant health and agriculture," he says on Linked In. "We use molecular, genetic, and epidemiological concepts to understand drivers of vector-borne transmission of pathogens and utilize genetic technologies (e.g. RNAi and CRISPR), to improve agriculture productivity and sustainability."
Hasegawa received his bachelor of science degree in biochemistry in 2007 from UC Riverside and his doctorate in biology from Clemson University in 2013.
The mission of the Crop Improvement and Protection Research Unit is to improve germplasm of lettuce, spinach and melon, determine basic biology of viral, fungal and bacterial diseases affecting these crops, develop alternatives to methyl bromide as a soil fumigant for control of soilborne pests in strawberry and vegetables, reduce postharvest losses of lettuce, develop scientifically based organic crop production practices, and develop methods for control of weeds. (See more on the Pacific West Area website.)
"More than 90 percent of the lettuce sold in the United States is grown in California, and the majority of production from April through October occurs in the Salinas Valley, while production form November through March occurs in California's Imperial Valley," according to keepcaliforniafarming.org.
The UC Statewide Integrated Pest Management Program (UC IPM) says this about thrips: "Thrips, order Thysanoptera, are tiny, slender insects with fringed wings. They feed by puncturing the epidermal (outer) layer of host tissue and sucking out the cell contents, which results in stippling, discolored flecking, or silvering of the leaf surface. Thrips feeding is usually accompanied by black varnishlike flecks of frass (excrement). Pest species are plant feeders that discolor and scar leaf, flower, and fruit surfaces, and distort plant parts or vector plant pathogens. Many species of thrips feed on fungal spores and pollen and are often innocuous. However, pollen feeding on plants such as orchids and African violets can leave unsightly pollen deposits and may reduce flower longevity. Certain thrips are beneficial predators that feed on other insects and mites."
"Thrips can readily move long distances floating with the wind or transported on infested plants, and exotic species are periodically introduced," UC IPM notes./span>
The U.S. Department of Agriculture's Agricultural Research Service (USDA-ARS) is gearing up for a ribbon-cutting ceremony and facility tour on Tuesday, Jan. 7 at its newly constructed Honey Bee Research Facility on Bee Biology Road, University of California, Davis.
The event is scheduled to begin at 1 p.m. The site is located next to the Harry H. Laidlaw Jr. Honey Bee Research Facility.
“The focus of this new USDA-ARS honey bee research program is to develop technology that improves colony survivorship through long-term studies of multiple stress factors,” a spokesman said. “These new facilities support two recently hired researchers: Drs. Arathi Seshadri and Julia Fine. These new scientists and associated technical staff are members of the Invasive Species and Pollinator Health Research Unit, whose mission is to develop and transfer integrated biologically based approaches for the management of invasive species and the improvement of pollinator health. The research team collaborates with federal, university, non-governmental and industry partners conducting research to improve honey bee survival and beekeeping sustainability in California and nationwide."
Research leader Paul Pratt of the Invasive Species and Pollinator Health Research Lab will give the welcoming address, followed by the presentation of colors by the Travis Air Force Base Honor Guard.
Among the speakers: Robert Matteri, director of the Pacific West Area, USDA-ARS; Anita Oberbauer, associate dean, UC Davis College of Agricultural and Environmental Sciences; and Kevin Hackett, national program leader, USDA-ARS.
The two new researchers will be introduced, followed by remarks by Darren Cox of Cox Honey of Utah, past president of the American Honey Producers' Association; Jackie Parks-Burris, past president of the California State Beekeepers' Association; and Extension apiculturist Elina Lastro Niño of the UC Davis Department of Entomology and Nematology and the Harry H. Laidlaw Jr. Honey Bee Research Facility. Niño also directs the California Master Beekeeper Program.
The event is open to invited guests. All guests are invited to tour the new facilities following the program. A stakeholder meeting is set from 2:30 to 3:30 p.m. in the Laidlaw bee facility classroom. For more information,contact Platt at email@example.com./span>
They buzz toward a blossom, sip nectar, and then head for another blossom. Typical, right?
But there's much more going on than you think.
It's not just the nectar that she's scented.
UC Davis community ecologist Rachel Vannette has just published a paper in New Phytologist journal that shows nectar-living microbes release scents or volatile compounds, too, and can influence a pollinator's foraging preference.
The groundbreaking research shows that nectar-inhabiting species of bacteria and fungi “can influence pollinator preference through differential volatile production,” said Vannette, an assistant professor in the UC Davis Department of Entomology and Nematology.
“This extends our understanding of how microbial species can differentially influence plant phenotype and species interactions through a previously overlooked mechanism,” Vannette said. “It's a novel mechanism by which the presence and species composition of the microbiome can influence pollination.”
“Broadly, our results imply that the microbiome can contribute to plant volatile phenotype,” she said. “This has implications for many plant-insect interactions.”
Their paper, titled “Nectar-inhabiting Microorganisms Influence Nectar Volatile Composition and Attractiveness to a Generalist Pollinator,” may explain in part the previous documented extreme variation floral volatiles that Robert Junker of University of Salzburg, Austria, and his team found; New Phytologist published their work in March 2017.
In their study, the Vannette team researchers first examined field flowers for the presence of nectar-inhabiting microbes, and in collaboration with co-authors Caitlin Rering and John Beck of the U.S. Department of Agriculture's Agricultural Research Service (USDA-ARS), Gainesville, Fla, characterized the headspace of four common fungi and bacteria in a nectar analog. Next, they used an intricate setup to quantify the antennal and behavior responses of honey bees to the chemical compounds. Finally, when they examined the scent of flowers in the field, they found that flowers which contained high densities of microorganisms also contained volatile compounds likely produced by those microbes, suggesting that microbial scent production can be detected and used by pollinators.
Although microbes commonly inhabit floral nectar, microbial species differ in volatile profiles, they found. “Honey bees detected most of the microbial volatiles or scents that we tested,” Vannette said, “and they distinguished the solutions of yeasts or bacteria based on volatiles only.” This suggests that pollinators could choose among flowers based on the microbes that inhabit those flowers.
The yeast Metschnikowia reukaufii produced the most distinctive compounds (some shared with the fruity flavors in wine) and was the most attractive of all microbes compared. This yeast is commonly found in flower nectar and is thought to hitch a ride on pollinators to travel from one flower to the next. Its scent production may help it attract pollinators, which then help the yeast disperse among flowers.
The Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis, provided the honey bees. More than 20 species of flowers--mostly natives--were used in the survey, including canyon delphinium or canyon larkspur (Delphinium nudicaule), sticky monkey flower (Mimulus aurantiacus), salvia (Lepechinia calycina) and purple Chinese houses (Collinsia heterophylla). The samplings were done in the spring and early summer, when the natives are at their peak.
Co-authors of the paper are Caitlin Rering, postdoctoral fellow at USDA-ARS, Gainesville, Fla.; John Beck researcher at USDA-ARS; Griffin Hall, junior specialist in the Vannette lab; and Mitch McCartney in UC Davis Department of Mechanical and Aerospace Engineering.
The USDA and USDA-ARS funded the research.
About Rachel Vannette: She joined the UC Davis Department of Entomology and Nematology in September of 2015 from Stanford University where she was a postdoctoral fellow.
A native of Hudsonville, Mich., Vannette received her bachelor of science degree in biology with honors at Calvin College, Grand Rapids, Mich., and her doctorate in ecology and evolutionary biology from the University of Michigan, in 2011. Her dissertation was entitled “Whose Phenotype Is It Anyway? The Complex Role of Species Interactions and Resource Availability in Determining the Expression of Plant Defense Phenotype and Community Consequences.”
In her PhD research, she examined how variation in nutrient availability and plant associations with mycorrhizal fungi belowground influenced defense chemistry in milkweed plants and the performance of a specialist herbivore (Danaus plexippus). She found that resource-based tradeoffs can in part explain plant allocation to antiherbivore defense and mycorrhizal fungi. This work also describes that plant genotypes vary in their investment in defense and associations with below ground fungi.
As a Stanford University postdoctoral fellow, funded by a life sciences research fellowship, Vannette examined the community ecology of plant-associated microorganisms. Using diverse systems, she studied the assembly of microbial communities, microbial response to anthropogenic changes like habitat fragmentation, and microbial effects on plant-pollinator interactions.
The National Wildlife Research Foundation featured Vannette's research on monarchs and milkweed in its March 11, 2013 piece on “Catering to Butterfly Royalty." The article, by author Doreen Cubie, focused on Vannette's research as a graduate student at the University of Michigan. Vannette and advisor Mark Hunter studied five common species of milkweeds, the host plant for monarchs. They found that climate change may disrupt the chemistry of milkweeds, and encouraged gardeners to help the monarchs by planting more of these critical host plants./span>
Roger Vargas is in the thick of fruit-fly research and he probably wishes those insects would thin out.
He's a research entomologist at the USDA-ARS Pacific Basin Agricultural Research Center in Hilo, Hawaii. For those who don't deal with acronyms, that's the Agricultural Research Service of the U.S. Department of Agriculture.
Vargas' key research interests include mass rearing, sterile insect technique, ecology, biological control, and area-wide integrated pest management (IPM) of fruit flies.
Vargas will be at the University of California, Davis, on Wednesday, Feb. 9 to speak on "Area-Wide Fruit Fly Programs against Fruit Flies in Hawaii, French Polynesia and California." His talk, sponsored by the UC Davis Department of Entomology and part of its winter seminar series, is set from 12:10 to 1 p.m. in 1022 Life Sciences Addition, corner of Hutchison and Kleiber Hall drives.
The lecture will be webcast live at http://uc-d.na4.acrobat.com/ucsn1/ and then archived here. He plans to cover current area-wide management programs against Bactrocera fruit flies in Hawaii, French Polynesia, and California.
"Fruit flies (Diptera: Tephritidae) are among the most economically important pests attacking soft fruits worldwide," Vargas says. "Bactrocera is a tephritid fly genus of at least 440 species distributed primarily in tropical Asia, the south Pacific, and Australia. However, these species have been spreading throughout the world at an alarming rate over the past 15 years.
"Oriental fruit fly (B. dorsalis) has become established and is spreading throughout French Polynesia.
"Carambola fruit fly (B. carambolae) is established and spreading throughout areas of South America.
"B. invadens, B. latifrons and melon fly (B. cucurbitae) are established and spreading in Africa.
"The peach fruit fly (B. zonata) is established and spreading in Africa and the Mediterranean region."
In fact, Vargas says, every year Bactrocera species are accidentally introduced from various parts of the world into California, requiring expensive treatment programs.
For an up-close and personal look at a fruit fly, check out the USDA-ARS photo of a Oriental fruit fly laying eggs in a papaya (below).
Coming soon...to a fruit near you...