- Author: Kathy Keatley Garvey
But agriculturists and scientists have.
The spotted-wing drosophila (SWD), Drosophila suzukii, is an agricultural pest that is super tiny.
It's approximately 2 to 4 millimeters in length with a wingspan of 5 to 6.5 millimeters. One millimeter is approximately 0.039 inches. There are 25.4 millimeters in 1 inch. So, the adult is about the size of a grain of sand, which can measure 0.5 to 2 mm in diameter.
SWD, native to southeast Asia and first discovered in California in 2008, lays its eggs in such soft-skinned, ripening fruits as strawberries, raspberries, cherries, blueberries, peaches, nectarines, apricot and grape.
In 2008, the first year of its discovery in California, the economic loss attributed to this pest amounted to $500 million. Latest statistics from 2015 indicate a $700 million national economic loss.
Lead author of the paper, “Transcriptome Analysis of Drosophila suzukii Reveals Molecular Mechanisms Conferring Pyrethroid and Spinosad Resistance,” is Christine Tabuloc, then a doctoral candidate and now a postdoctoral researcher working under the mentorship of Professors Chiu and Zalom.
"In this work, we leveraged high throughput sequencing to identify biomarkers of insecticide resistance in D. suzukii,” Tabuloc explained. “We found that different genes are responsible for resistance to different chemicals. Specifically, we found that genes involved in metabolism are highly expressed in flies resistant to pyrethroid insecticides. We also observed evidence of two different mechanisms of resistance in 2 lines generated from a single spinosad-resistant population. We found an increased expression of metabolic genes in one line and increased expression of cuticular genes in the other.”
Tabuloc added that “our work has enabled for the detection of resistance in California populations, and we are currently doing a nationwide screening to determine whether resistance is now present in other states. Currently, we are working with the Zalom lab to use the results of our assays to try and combat resistance. There are experiments in progress trying to increase the efficacy of insecticides by blocking some of the genes involved in resistance, such that the enzymes encoded by those genes have decreased function."
A giant in the entomological world, Zalom directed the UC Statewide Integrated Pest Management Program for 16 years. He is an Honorary Member of the Entomological Society of America (ESA), the highest ESA honor, and he served as its president in 2014.
“This work not only represents good science; it has very practical implications," Zalom said. He and Tabuloc presented results of the work at a special berry grower seminar on insecticide resistance organized by UC Agriculture and Natural Resources (UC ANR) Farm Advisor Mark Bolda, strawberry and caneberry farm advisor in Santa Cruz, Monterey and San Benito counties, Mark Bolda in Watsonville.
"The presentations were extremely well-received," Zalom noted. "The original program was targeted for about 1.5 hours, but the meeting extended to over three hours due to the extent of questions and great discussion that followed. Growers and their consultants are hungry for new information that they find interesting and potentially useful, and this work was clearly of interest to them.”
Said Bolda: “The research was top shelf and the need, of course, is very great. Some of the information that Frank and Christine presented has been put into immediate use in the industry.”
What most people don't know is that Bolda was the first to discover the pest in North America. That was in 2008.
"He asked me to come down to look at it and the problem...we weren't able to get an actual species identification until 2009!" Zalom said.
As the pest continues to spread throughout much of the country, anxious growers are worried about its increased resistance to pesticides. The UC Davis research team is alleviating that worry.
- Author: Kathy Keatley Garvey
It's 3:47 p.m., on Sunday, June 4. I am watching a honey bee nectaring on a zinnia in our pollinator garden. She collects, lingers and then leaves.
It was like (A) Apis mellifera to (Z) zinnia. I thought: "A honey bee, Apis mellifera, is leaving a pink zinnia after gathering nectar and pollen for her colony. Everyone must leave what they love to become who they want to be or what they want to become."
So it is with commencements. Molecular geneticist-physiologist Joanna Chiu, professor and vice chair of the UC Davis Department of Entomology and Nematology, captured this image at a PhD commencement today and posted it on Twitter: "What do we have here? Congratulations Dr. Cai, Dr. Griebenow, Dr. Lewald and Dr. Tabuloc!"
That would be Yao Cai, Christine Tabuloc and Kyle Lewald of the Chiu lab and Zachary Griebenow of the Phil Ward lab. Former doctoral students, then doctoral candidates...and now PhDs...
Kyle? Member of the Integrative Genetics and Genomics Graduate Group. Others? Entomology Graduate Group.
Professor Chiu captured it perfectly! What a proud and glorious moment!
- Author: Kathy Keatley Garvey
Remember the spotted-wing drosophila, Drosophila suzukii?
Native to Southeast Asia, it infests soft-skinned fruits such as strawberries, raspberries, cherries, blueberries, blackberries, peaches and grapes. Scientists first detected it in the United States (central coastal region of California) in 2008.
If you attend UC Davis doctoral candidate Christine Tabuloc's exit seminar at 4:10 p.m., Wednesday, Feb. 15--in-person or virtually--you'll get a grasp of the work she's doing involving D. suzukii, a worldwide pest, and D. melanogaster, a common species used worldwide as a model organism in genetics.
Tabuloc, advised by molecular geneticist and physiologist Joanna Chui, professor and vice chair of the UC Davis Department of Entomology and Nematology, will speak on "Environmental and Anthropogenic Impact on Insect Gene Expression and Physiology" in 122 Briggs Hall. Her seminar also will be virtual. The Zoom link:https://ucdavis.zoom.us/j/95882849672.
Professor Chiu will introduce her. A pre-seminar coffee session is set from 3:30 to 4:10 p.m. in Briggs 158.
"Natural environmental factors and anthropogenic disturbances can modulate gene expression, resulting in alteration of organismal phenotype," Tabuloc says in her abstract. "In the first part of my thesis project, I used Drosophila melanogaster as an insect model to understand the mechanisms by which 24-hour light-dark cycles can regulate rhythmic changes in the chromatin to generate circadian rhythms of gene expression and orchestrate daily biological rhythms. I observed that two clock proteins, CLOCK and TIMELESS, regulate daily rhythmicity in the binding of BRAHMA, a chromatin remodeler, to DNA spanning clock-controlled genes to facilitate their rhythmic gene expression cycles. Moreover, because TIMELESS degrades in the presence of light, my results provide new insights into how light affects DNA structure and gene expression."
"In the second part of my thesis project, I investigated the impact of insecticide applications on the fruit pest Drosophila suzukii," Tabuloc said. "Specifically, I performed RNA sequencing analysis on D. suzukii flies that are either susceptible or resistant to common insecticides to determine genetic mechanisms underlying insecticide resistance in this agricultural pest. My results revealed that enhanced metabolic detoxification confers pyrethroid resistance while spinosad resistance is the result of both metabolic and penetration resistance. Finally, we identified alternative splicing
as an additional mechanism of resistance. These results will facilitate the development of efficient molecular diagnostics to identify insecticide resistance in the field and enable growers to adjust D. suzukii spray programs to control this devastating pest more effectively."
Christine received her bachelor of science degree in biochemistry and molecular biology from UC Davis in 2015. She joined the Chiu lab as an undergraduate research assistant in 2012. "Much of my work in the lab has involved different agricultural pests and investigating the molecular aspects contributing to the insect's ability to be an effective pest," she says on the Chiu lab website. "My current focus is to investigate the effects of climatic change on gene expression of an invasive pest and determine whether there is a correlation to resistance and survival. In addition to pest management research, I am also studying a kinase of a core clock protein in Drosophila melanogaster and hoping to dissect its functional contribution to the molecular oscillator."
The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. They are coordinated by urban landscape entomologist Emily Meineke, assistant professor. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
- Author: Kathy Keatley Garvey
They're featured in a recent Entomology Today blog, published by the Entomological Society of America (and written by yours truly) and headlined "Bugs and Beat."
Well, move over. Think about the three-cornered alfalfa hopper (Spissistilus festinus) and the male insect organ, the aedeagus.
A group of seven graduate students in the UC Davis Department of Entomology and Nematology performed such tunes as “E Major Homeboy (Spissistilus festinus),” “Tragedy (of the Clocks),” and “Jackson's Song (Aedeagal Bits),” as well as a cover song, “Island in the Sun” by Weezer. All are members of the UC Davis Entomology Graduate Student Association, headed by Brendon Boudinot, president.
Graduate student Michael Bollinger of the lab of Frank Zalom (a former president of the Entomological Society of America) composed the first three tunes.
The performance capped a day of insect-related activities that included maggot art, cockroach races, nematode identification, scavenger hunts, and honey tasting. Bugs rule!
- Molecular geneticist and drummer Yao “Fruit Fly” Cai of the Joanna Chiu lab dressed in a fruit fly costume (Drosophila melanogaster), which he described as “our favorite model organism in Insecta!”
- Bark beetle specialist and rhythm guitarist Jackson “Darth Beetle” Audley of the Steve Seybold lab portrayed an Asian longhorned beetle (Anoplophora glabripennis).
- Honey bee researcher and bass guitarist Wei “Silverfish” Lin of the Brian Johnson lab wore a costume that celebrated his moniker (Lepisma saccharina), a small, wingless insect in the order Zygentoma.
- Ant specialist and keyboard artist Zachary “Leptanilla” Griebenow of the Phil Ward lab dressed as “a generic male leptanilline ant (Formicidae: Leptanillinae).” However, he noted “the yellow color is not anywhere near so vivid in real life.”
- Systematist and tenor saxophonist Jill “Jillus Saximus” Oberski of the Phil Ward lab dressed as a “generalized heteropteran,” which she described as “most likely a member of the family Acanthosomatidae (shield bug) or Pentatomidae (stink bug). My family and friends have called me Jillybug, so I came to be the band's representative of Hemiptera.”
- Molecular geneticist and vocalist Christine “The Clock” Tabuloc of the Joanna Chiu lab wrapped herself in butterfly wings.
- Ant specialist and bass guitarist Brendon “Hype Man-tis” Boudinot of the Phil Ward lab dressed in a green helmet, a blue and gold EGSA bee shirt, and a UC Davis cow costume to showcase his department and campus-wide love of bovines.
Drummer Yao Cai, who grew up in Southeast China and holds an undergraduate degree in plant protection and a master's degree from China Agricultural University, has been playing drums since age 17. “We formed as a short-lived band for a show. After that, I realized that I really wanted to keep playing and improved my drum techniques. Thus, we started another band in college and played for six years in college, as an undergrad and graduate student.
“It is very interesting that I was in a band that was the first band in Department of Entomology in China Agricultural University and now we started the first band in Department of Entomology at UC Davis,” Cai added.
Rhythm guitarist Jackson Audley said he “started learning to play the guitar when I was about 11 or 12-ish. The first band I joined was a Blink-182 cover band, in which I played the bass guitar, and we played together for most of eighth grade. Then in early high school I joined a Smashing Pumpkins/Radiohead cover band as the second guitarist. Shortly after joining that band, we started making predominantly original music. By the end of high school, we had played a few small shows around the Atlanta area and had recorded a few songs. Unfortunately, the band did not survive the transition into university and we broke up.”
Since then he's mostly played “for fun, and I like to jam with folks.”
Jill Oberski, a native of Twin Cities, grew up mostly in Chaska, “a sleepy suburb of Minnesota.” She received her bachelor's degree in Macalester College in Saint Paul, Minnesota, where she double-majored in biology and German studies.
“I started playing the piano in kindergarten and switched to saxophone in fifth grade,” Oberski related. “I played classical and jazz in my school bands from sixth grade through college and pit orchestra, pep band, and marching band in high school as well. I've always been better at classical than rock, jazz, or Latin.”
“I probably reached my highest point in late high school, when I served as co-section leader for the saxes in the Minnesota all-state symphonic band,” Oberski said. “We even got to play a concert in Minneapolis' orchestra hall. These days I'm only involved in the entomology band and some very casual ukulele playing.”
Brendon Boudinot, who received his bachelor's degree in entomology at the Evergreen State College in Olympia, Washington, performed on a metallic sky-blue bass and served as emcee. “I just love art,” said Boudinot, president of the UC Davis EGSA. “Music is a family thing for me in a number of different ways. Although I have played instruments alone or in groups for many years, nothing really clicked in me until I heard Michael and Yao play together. They shred.”
Vocalist Christine Anne Tabuloc, who grew up in the Los Angeles area and received her bachelor's degree from UC Davis in biochemistry and molecular biology, says she does not play an instrument. “I'm far less talented than everyone else in the group,” she quipped. “I've been singing for as long as I can remember. I've been writing lyrics since elementary school. However, I never got around to getting music written for them. I was in choir before and have had solos but that's pretty much it.”
Bass guitarist Wei Lin, who grew up in Xiamen, “a beautiful island in southern China,” received his bachelor's and master's degree at China Agricultural University, majoring in plant protection and entomology. “This was my first experience in a band. I just started to learn bass last year when this band was built.”
Following the four-set gig, Boudinot told the appreciative crowd, “That's all we know!”
Pending performances? “The band,” he said, “is on hiatus.”
Or diapause.
(Editor's Note: Listen to a clips of their music on YouTube.)
