Other beetles--cucumber beetles--ravage agricultural crops, drawing millions of foes.
Enter Jasmin Ramirez Bonilla, a UC Davis graduate student in entomology, who is seeking to control these pests on melons through more effective integrated pest management (IPM) strategies.
Jasmin, who plans to complete her master's degree in the spring of 2022, recently presented her thesis proposal, “Advancing Integrated Pest Management Strategies for Cucumber Beetles in California,” to the UC Davis Department of Entomology and Nematology at a Zoom session.
“The beetle of focus for my thesis is the Western striped cucumber beetle, Acalymma trivittatum,” said Jasmin, who studies with major professor and agricultural entomologist Ian Grettenberger, a Cooperative Extension specialist in the UC Davis Department of Entomology and Nematology.“ A second species, the Western spotted cucumber beetle, Diabrotica undecimpunctata undecimpunctata--a milder pest but still a pest of melons-- is also part of my project but not the primary subject of my studies.”
Her thesis project consists of three objectives:
- Characterize the non-crop and overwintering habitat
- Clarify short-distance dispersal dynamics after harvest
- Evaluate the utility of the aggregation pheromone, vittatalactone
Both species feed on muskmelons, Cucumis melo. “These include honeydew melon, cantaloupe, crenshaw, and cassava,” she said. “However, Acalymma is the specialist.” Cucumber beetles are pests of plants in the Cucurbitaceae family,which includes melons, gourds, cucumbers, squash and pumpkin.
Of key concern is “the lack of effective IPM tools for the management of cucumber beetles, especially the western striped cucumber beetle,” she said. “There is a critical need to visit this system and revisit the ecology to have a clearer understanding of the non-crop habitat uses and dispersal dynamics to improve and optimize the scouting and monitoring strategies. In addition, one way to monitor and manage insect pests is using semiochemicals such as aggregation pheromones and kairomones—for example, cucurbit blossom volatiles--which are of interest to be combined and studied their efficacy attraction.”
Preliminary data for one of her experiments indicates that the synthetic aggregation pheromone, vittatalactone, attracts the western striped cucumber beetle and the spotted cucumber beetle. “This pheromone was mimicked from airborne volatiles produced by male beetles, Acalymma vittatum, the cousin of the western striped cucumber beetle,” Bonila related. “This pheromone is a potential monitoring tool for managing these beetles and minimize the intensive applications of insecticides on the field.”
What sparked her interest in entomology? When she worked as a field research assistant for six months in 2017 with the UC Cooperative Extension in Woodland and sampled Lygus damage in sunflower fields.
“After this field assistant position, I worked as a junior specialist on an alfalfa weevil project to improve management in alfalfa,” Jasmin related. This was a research grant of the late Larry Godfrey (1956-2017), an Extension entomologist based in the UC Davis Department of Entomology and Nematology. Godfrey, the principal investigator of the grant, worked with co-principal investigator Yolo County Farm Advisor Rachael Long until his death in April.
Long invited Jasmin to apply for the position. “That increased my interest in bugs,” Jasmin said. “There were so many different species and I was constantly collecting plethora of insects in each sample!”
A native of Guatemala, Jasmin moved to the United States at age 15 with her family. “Even though I wasn't born here, I still consider myself Guatemalan,” she related. “My family lives in Los Angeles and I attended Reseda High School in the San Fernando Valley.”
Jasmin, who received her bachelor's degree in earth system science at UC Merced in 2016, worked as a vegetation and ecological restoration intern with the National Park Service before enrolled in the UC Davis graduate program.
But it's the insects—particularly cucumber beetles—that fascinate her.
Agricultural entomologist and Cooperative Extension specialist Ian Grettenberger, who joined the faculty of the UC Davis Department of Entomology and Entomology in January 2019, targets a variety of pests, including western spotted and striped cucumber, beetles, armyworms, bagrada bugs, alfalfa weevils, aphids, and thrips
Grettenberger, who fills the vacated position of Larry Godfrey (1956-2007), received his bachelor of science degree in biology, with an ecology, evolution and organismal emphasis (honors Program) in 2009 from Western Washington University, Bellingham, Wash., and his doctorate in entomology in 2015 from Pennsylvania State University, State College, Pa. He served as a postdoctoral researcher in the Godfrey lab and later, the Frank Zalom lab, before accepting his current appointment of assistant Cooperative Extension specialist.
Grettenberger's fields of expertise include field and vegetable crops; integrated pest management; applied insect ecology, and biological control of pests.
Among his current grants:
- Protection of rice from invertebrate pests
- Management of key cotton arthropod pests with insecticides and acaricides, a proactive approach to prepare for the invasion of the tomato leafminer (Tuta absoluta) into California
- Detection, biology and control of the exotic Swede midge (Contarinia nasturtii) for California cole crops
- Management of the western spotted and striped cucumber beetle in melon production
- Biological control of the bagrada bug
- Insecticide resistant alfalfa weevils in the western United States:Quantifying the scope of resistance and implementing a plan to manage the threat
- Insecticide resistance monitoring and evaluation of efficacy of current chemical tactics for managing aphids and thrips in lettuce
How did you get interested in entomology? Can you recall an occasion that sparked your interest?
I had biologist parents, and was drawn into entomology at a pretty young age. I spent plenty of time looking in flowers and turning over logs looking for insects. Once I started thinking about going to graduate school for entomology, I decided to focus on the intersection of agricultural entomology and insect ecology. I wanted to work on applied issues in entomology.
How would you describe yourself?
I like tackling problems, which has worked out well with my work in applied entomology and extension. I can be intensely focused and immensely distracted, which I would say has its pluses and minuses.
What do you like best about your work?
I love working in applied entomology and that I get to use research to better understand pests and work to develop IPM tools. The breadth of crops I cover is both a bit overwhelming but immensely exciting because of the diversity in pest issues, types of tactics that are applicable, and interesting ecological/biological questions among the various crop pests. I also get to work with great people, both within my lab and with all of the various collaborators/cooperators. I have met and worked with a lot of fantastic people this first year, and I also think my lab is off to a great start.
Where were you born and where did you spend your childhood?
I was born in Portland, Ore., but I primarily grew up in Olympia, Wash. As you might imagine, I grew up with lots of rain, but in a beautiful area.
What are your research plans/goals here at UC Davis? What drew you to UC Davis?
Thus far, I have been focused on projects in crops where there has historically seen solid research by UC Davis (such as rice and cotton) and have been developing new projects and collaborations. For better or worse, IPM is never static, so my research will be continually evolving to address pest management needs and has already been shifting this first year. Because I have an extension appointment, stakeholder needs have driven much of my work and this will continue to be a theme.
I was drawn to Davis by the many opportunities it would afford working in agricultural entomology. The department has a great reputation academically and the people in it are great as well. I also would have (and have had) the opportunity to connect with many other great researchers in the UC system, both campus- and county-based. There are many crops and pests to work on. We are quite literally surrounded by crops I work in, including alfalfa, rice, and tomatoes. I even found some alfalfa weevil on my run last weekend.
What do you like to do in your leisure time?
My primary hobby is running, ideally on trails and long distances. I can deal with the nearly zero elevation gain in our area, but I like to get out to where there are some hills. I also like to be outdoors in general and spending time with my family (wife/dog/cat; dog will go on adventure runs with us, cat only gets the backyard).
What would people be surprised to know about you?
I don't like all foods, but I will try basically anything just to see what it tastes like. I think some people are also surprised by the amount of food I can eat at one time.
Now you can not only see a stag beetle, you can wear one. In fact, four of them.
Entomologist Stacey Lee Rice won the UC Davis Entomology Graduate Students Association's annual t-shirt design contest with her artistic stag beetle t-shirt that's already a conversation starter. The shirt is available for sale at https://mkt.com/UCDavisEntGrad
Rice, a junior specialist in the lab of Extension entomologist Larry Godfrey of the UC Davis Department of Entomology and Nematology faculty, says the harmony between nature and insects inspires her art.
The stag beetle t-shirt design not only incorporates her love for stag beetles (family Lucanidae) but illustrates the “geometric patterns that are hidden in the deciduous forests they dwell in,” said Rice, who as a scientist and artist, enjoys fusing science with art.
She loves the complexity and beauty of insects. "I'm captivated by insects' structural biology, ability to evolve over time and the intricate ways in which they communicate,” she said.
A repeat winner, Rice also won the EGSA's 2015 t-shirt contest with her depiction of a wasp riding a penny-farthing or high-wheel bicycle. Both t-shirts, along with scores of other winning t-shirts, are available for sale on the EGA website, https://mkt.com/UCDavisEntGrad
Her research in the Godfrey lab, in collaboration with Ian Grettenberger, postdoctoral research associate, involves investigating the biology and behavioral ecology of the bagrada bug, Bagrada hilaris, an invasive species from Africa. The now widespread stink bug attacks cole crops, including broccoli, cabbage, collards, arugula, cauliflower, kale, and mustard.
“Dr. Grettenberger has taught me how to manage time and stay organized in order to execute an effective research plan,” Rice said, “and I am inspired by his enthusiasm to solve problems.”
“With the support of Dr. Larry Godfrey (Extension entomology, UC Davis Department of Entomology and Nematology), I have been motivated to pursue my Ph.D," Rice said. "I'm grateful for his commitment to fostering my intellectual growth, and dedication to mentoring a young woman scientist in a field where women are frequently underrepresented.”
A native of Roseville, Rice received her bachelor's degree in biological sciences with a minor in medical-veterinary entomology in March 2015. Her career goal, to become a professional research entomologist, stems from her childhood interest in the biological sciences.
“I'm particularly interested in integrated pest management practices that could have real world impact,” Rice said. “By understanding the biology and behaviors of pest insects, as well as their interaction with other organisms, the reliance on heavy pesticide use in agriculture may become minimized and more targeted. “
Rice hopes to enroll in graduate school in autumn 2017. Meanwhile, she continues to share her fascination for insects with friends, family and the Davis community.
For several years, Rice was active in the UC Davis Entomology Club, advised by forensic entomologist Robert Kimsey of the UC Davis Department of Entomology and Nematology faculty. “I consider Bob Kimsey as my mentor and friend," she said. "Along with the various projects of the entomology club, he has instilled in me a deep curiosity of the natural world and a strong desire to give back to the community as an entomologist.”
Rice's award-winning t-shirt first went on sale at the Entomological Society of America/International Congress of Entomology meeting, held in early November in Orlando, Fla.
EGSA treasurer Cindy Preto of the Frank Zalom lab is coordinating the t-shirt sales. The themes include honey bees, beetles, a wasp, a moth, weevils (“See No Weevil, Hear No Weevil and Speak No Weevil") and “Entomology's Most Wanted” (malaria mosquito, red-imported fire ant, bed bug and house fly). One of the best sellers is “The Beetles,” mimicking The Beatles' album cover, “Abbey Road.” All proceeds benefit EGSA.