- Author: Kathy Keatley Garvey
The two don't go together, but how can we protect both crops and pollinators?
"Pesticides may be necessary in today's cropping systems but large monocultures have resulted in the need for significant use of insecticides, herbicides and fungicides," says honey bee expert Maryann Frazier, senior extension associate, Penn State University.
"New chemistries, such as neonicitinoids, have their advantages but the persistent use of synthetic pesticides, especially in bee-pollinated crops and/or crops visited by bees to collect nectar or pollen, such as corn, has resulted in significant pesticide exposure to bees."
Frazier, fresh from a trip to Kenya to help beekeepers with varroa mite problems, will be on the University of California, Davis, campus on Wednesday, April 2 to discuss "The Pesticide Conundrum: Protecting Crops and Pollinators." Her seminar, hosted by the UC Davis Department of Entomology and Nematology, will be from 12:10 to 1 p.m., in 122 Briggs Hall.
"Over the past seven years our lab has analyzed over 1,200 samples of mainly pollen, wax, bees and flowers for 171 pesticides and metabolites," she said. "We have found 129 different compounds in nearly all chemical classes, including organophosphates, pyrethroids, carbamates, neonicotinoids, chlorinated cyclodienes, organochlorines, insect growth regulators, fungicides, herbicides, synergists, and formamidines. Further, we have identified up to 31 different pesticides in a single pollen sample, and 39 in a single wax sample. An average of 6.7 chemicals are found in pollen samples. However, the pesticides found most often and at the highest levels are miticides used by beekeepers for the control of varroa mites."
In her talk, Frazier will discuss these results, additional studies and concerns about "the synergistic effects of pesticides, systemic pesticides and sub-lethal impacts, including those on immune function, memory and learning and longevity, as well as the question of toxicity associated with adjuvants/inert ingredients."
Helping to coordinate the seminar with assistant professor Brian Johnson is Mea McNeil of San Anselmo, master beekeeper and writer.
Frazier, senior extension associate at Penn State for the past 25 years, is responsible for honey bee extension throughout Pennsylvania and cooperatively across the Mid-Atlantic region. Frazier works with other members of the PSU Department of Entomology to understand how pesticides are impacting honey bees and other pollinators. She's taught courses in beekeeping, general entomology and teacher education and is involved with the department's innovative public outreach program. In addition, she works with a team of U.S. and Kenyan researchers to understand the impacts of newly introduced varroa mites on East African honey bee subspecies and to help Kenyan beekeepers become more productive.
Frazier holds two degrees from Penn State: a bachelor of science degree in agriculture education (1980) and a masters of agriculture in entomology (1983), specializing in apiculture. She is a former assistant state apiary inspector in Maryland and also has worked as a beekeeping specialist in Sudan and later in Central America.
Frazier appears in a YouTube video, posted July 23, 2012 on the declining bee population. The brief clip was excerpted from Frazier's Spring 2012 Research Unplugged talk titled "Disappearing Bees: An Update on the Search for Prime Suspects." The abstract: She discusses the decline of pollinators and the prime suspects behind it. Some of these suspects include the use of pesticides, on both small and large scales, that destroy food sources for bees; agribusiness practices such as monocropping, in which the same single crop is planted year after year, eliminating the plant diversity pollinators need; stress caused by transporting the bees across country for commercial pollination needs; and threats such as nosema disease, viruses and mites.
The UC Davis Department of Entomology and Nematology plans to video-record her seminar for later posting on UCTV.
- Author: Kathy Keatley Garvey
Professor James R. Carey of the UC Davis Department of Entomology will tell you why.
He will discuss the invasion of tropical fruit flies in California at his seminar from 12:05 to 1 p.m., Wednesday, April 3 in Room 1022 of the Life Sciences Addition, corner of Hutchison and Kleiber Hall drives.
Carey's seminar, titled "From Trickle to Flood: The Large-Scale, Cryptic Invasion of California by Tropical Fruit Flies," is the first in the department's spring-quarter seminar series. It's open to all interested persons, and it will be recorded and available for later viewing on UCTV.
"Despite aggressive and costly efforts by government agencies to prevent their introduction, establishment and spread, California has experienced an inexorable march of tropical fruit flies (Tephritidae) into the state with three-fold more species detected and thousands more flies captured than in all other mainland U.S. states combined," Carey says.
"Since 1954 when the first fly was detected a total of 17 species in 4 genera and 11,386 individuals (adults/larvae) have been detected at over 3,348 locations in 330 cities. My colleagues and I conclude from spatial mapping analyses of historical capture patterns and modeling that, despite the approximately 250 emergency eradication projects that have been directed against these pests by state and federal agencies, a minimum of 5 and as many as 9 or more tephritids are established and widespread. This list includes three of the most economically-important species in the world—the Mediterranean, Mexican and oriental fruit flies."
In his seminar, Carey will "outline and discuss the evidence for our conclusions with particular attention to the incremental, chronic, and insidious nature of the invasion involving ultra-small, barely-detectable populations. I will consider the more general implications of our results in scientific, economic, and operational contexts of invasion biology, as well as ethical issues concerned with the purposeful obfuscation of historical fruit fly detection data at individual, administrative and institutional levels."
Carey, former vice chair of the Department of Entomology, focuses his research on insect demography, mortality dynamics, and insect invasion biology. He received his bachelor and master of science degrees from Iowa State University (1973; 1975) and his doctorate in entomology from UC Berkeley (1980).
Highly recognized, he is a fellow of the American Association for the Advancement of Science, the Gerontological Society of America, the California Academy of Sciences, and the Entomological Society of America.
Carey is a noted authority on the invasion of the tropical fruit flies. He served on the California Department of Food and Agriculture's Medfly Scientific Advisory Panel from 1987-1994, testified to the California Legislature "Committee of the Whole" in 1990 on the Medfly Crisis in California, and authored the paper "Establishment of the Mediterranean Fruit Fly in California" (1992, Science 258, 457).
- Author: Kathy Keatley Garvey
"Ants are the most successful group of social insects on the Earth," says Branstetter, Postdoctoral Fellow at the Smithsonian Institution, Washington, D.C. and a UC DAvis alumnus. "They occur in almost all terrestrial habitats and are often numerically dominant and ecologically important. Furthermore, ants are diverse. There are likely to be more than 20,000 species worldwide and among these species there is a staggering amount of morphological and behavioral variation."
"It's not just the red ant and black ant. Some species are predatory and have large trap-jaw mandibles. Some are farmers, growing fungus gardens inside their nests. Some are parasites of other ant species, living in host nests and taking advantage of a tricked worker force. And some have huge migrating colonies that go on massive raids to collect food. The list goes on..."
Branstetter is also intrigued by the diversity and is devoted to discovering and describing species and behaviors. "Most of my work focuses on using morphology and genetic data to determine what species are, but I also spend lots of time in the field making direct observations about behavior and ecology."
Branstetter, who received his doctorate in entomology in June 2012 from UC Davis (major professor Phil Ward), will speak on ”Uncovering the Origins of a Middle American Ant Radiation: Insights from Natural History, Biogeography and Molecular Data” from 12:10 to 1 p.m., Wednesday, Jan. 16 in Room 1022 of the Life Sciences Addition, corner of Hutchison and Kleiber Hall drive. His seminar will double as his exit seminar.
Born in Toledo, Ohio, Branstetter grew up in Kalamazoo, Mich. "It was not until I entered college at The Evergreen State College in Washington state that I became interested in science and eventually entomology," he says. His passion for entomology ignited in a class on "Insects and Plants of Washington" taught by Jack Longino.
That prompted Branstetter to specialize in myrmecology, the scientific study of ants.
He was hooked. Next: Graduate school at UC Davis.
The ants (genus Stenamma) that Branstetter studies are "special because they are an example of a group that originated in the temperate zone and later dispersed into the tropics. Within the tropics they have radiated in mid- to high-elevation wet forests, sometimes becoming the most dominant ant. This is in contrast to most other ants, which usually peak in diversity and abundance in the lowlands."
"It is my hope that studying Stenamma diversity and ecology will yield insights into the factors that have helped ants become so successful," Branstetter says. "Also, the genus has many undescribed species in Middle America. Describing these species and making identification keys will allow others, such as ecologists or conservation biologists, to identify them in their work. Of particular importance are the montane species, which may be in danger of extinction due to climate change."
If you miss Branstetter's seminar, not to worry. It will be recorded for later viewing on UCTV.
- Author: Kathy Keatley Garvey
It's Halloween tomorrow (Wednesday) but what's really frightening is Aedes aegypti, a mosquito that transmits the deadly dengue. According to the World Health Organization (WHO), dengue is the world's most rapidly spreading mosquito-transmitted disease.
Some 2.5 billion people, or about 40 percent of the global population, are at risk from dengue, WHO says. The disease infects between 50 to 100 million people a year. The most severe form afflicts some 500,000 a year, killing an estimated 2.5 percent or 22,000.
Enter Sarjeet Gill, professor of cell biology and entomology at UC Riverside. He'll speak on on "Bacterial Toxins in Disease Mosquito Vector Control" at a seminar from 12:10 to 1 p.m., Wednesday, Oct. 31 in Room 1022 of the Life Sciences Building, UC Davis.
His longtime colleague and good friend, Bruce Hammock, distinguished professor of entomology at UC Davis, will host him as part of the UC Davis Department of Entomology's fall seminar series.
"Aedes aegypti is an important vector of human diseases, such as dengue fever and yellow fever," Professor Gill says. "Its control has been attempted by eliminating breeding sites, using predators and with chemical insecticides. However, such control is still difficult because of operational limitations and the development of insect resistance. Therefore, Bacillus thuringiensis has been used for decades instead of physical and chemical control methods. B. thuringiensis israelensis is highly active against Aedes aegypti."
"The high insecticidal activity and the low toxicity to other organisms," Gill says, "have resulted in the rapid use of B. thuringiensis as an alternative for the control of mosquito populations. B. thuringiensis israelensis produces a variety of toxins that act synergistically to cause toxicity to larval populations."
Gill says his seminar "will discuss our current understanding of the mode of action of these toxins and provide evidence on how resistance to these toxins has not occurred in Aedes mosquitoes in the field even though B. thuringiensis israelensis has been used for more than three decades."
Gill’s laboratory focuses on two principal research activities. "The first area attempts to elucidate the mode of action of insecticidal toxins from the Gram positive bacteria Bacillus thuringiensis and Clostridium bifermantans," he says. "This research aims to identify novel toxins, and to gain a molecular understanding of how these toxins interact with cellular targets and thereby causing toxicity. The second area focuses on understanding mosquito midgut and Malpighian tubules function, in particular ion and nutrient transport, and changes that occur following a blood meal."
Gill, who received his doctorate from UC Berkeley, joined the UC Riverside Department of Entomology faculty in 1983. He helped establish the Department of Cell Biology and Neuroscience and also served as chair. Currently he is the co-editor of the journal Insect Biochemistry and Molecular Biology.
A noted scientist and a fellow of the American Association for the Advancement of Science, Gill received his doctorate in insecticide toxicology in 1973 from UC Berkeley. See his website.
If you miss his seminar, not to worry. It's scheduled to be recorded and then posted at a later date on UCTV. (See the index of previous Department of Entomology seminars posted on UCTV.)
/span>- Author: Kathy Keatley Garvey
That's why we're looking forward to hearing Bryony Bonning speak on "Novel Toxin Delivery Strategies for Management of Pestiferous Aphids" at the next UC Davis Department of Entomology seminar, scheduled from 12:10 to 1 p.m., Wednesday, April 18 in 122 Briggs Hall.
Aphids, Bonning says, transmit more than 275 plant viruses "that result in considerable economic loss within the agricultural sector."
Now that's a lot of plant viruses!
A professor with the Iowa State University's Department of Entomology, Bonning is closely linked to UC Davis. She's a former postdoctoral research associate in the Bruce Hammock lab, Department of Entomology. Hammock, a distinguished professor of entomology, worked with her from 1990 to 1994. Her specialty: genetic engineering and optimization of baculovirus insecticides.
Bonning returns here Wednesday with lots of credentials. She's an associate editor for the Journal of Invertebrate Pathology; a Fellow of the American Association for the Advancement of Science (AAAS); a member of the International Committee on Taxonomy of Viruses, Baculovirus Study Group; and a member of the International Committee on Taxonomy of Viruses, Dicistrovirus/Iflavirus Study Group.
Bonning received her bachelor's degree in zoology from the University of Durham, UK in 1985, and her doctorate in applied entomology from the London School of Hygiene and Tropical Medicine, University of London, UK in 1989.
In her abstract for Wednesday's talk, Bonning explains: "Viruses in the Luteoviridae are obligately transmitted by aphids in a persistent manner that requires virion accumulation in the aphid hemocoel. To enter the hemocoel, the virion must bind and traverse the aphid gut epithelium. The molecular mechanisms involved in this process are poorly understood. By screening a phage display library, we identified a peptide that binds to the gut epithelium of the pea aphid Acyrthosiphon pisum (Harris) and impedes the update of Pea enation mosaic virus from the pea aphid gut into the hemocoel. In this talk, the development of two novel aphid management technologies based on knowledge of pea aphid – Pea enation mosaic virus molecular interactions will be described. These technologies provide enhanced delivery of both gut active and neurotoxic peptides."
"I can hardly wait for Bryony Bonning to visit us and present a seminar," Hammock said. "She is one of our most productive alumni in continuing her work on insect developmental biology and green pesticides based on insect viruses and expanded this dramatically into exciting new areas. She is advancing fundamental virology while applying this knowledge in production agriculture in both insect control and in blocking transmission of plant diseases by insects. She clearly is the leader in insect control with recombinant viruses."
Her April 18th seminar promises to zero in on those dratted pea aphids. The more we know about them, the better we can control them.
And the good news is that many of the UC Davis Department of Entomology's seminars will be videotaped and later posted on UCTV.