Summer Research Program: Students Investigate Plant Viruses and Alternatives to Pesticides

Two science majors got the chance to literally dig into how environmental conditions affect our food in their Summer Research Program, reflecting just how hands-on student projects can get at SMC. Biology major and Music and Chemistry double minor Emily Hancock ’24 and Allied Health Science major Emma Cardinale ’24 investigated how aphids carrying viruses infect certain cereal crops. Their program, Plant Viruses, Vector Behavior, and Host Susceptibility, mentored by Biology Professor Kai Blaisdell, PhD, was both lofty and crucial: Identifying safe alternatives to pesticides used on the plants we eat.

The students began their research in Saint Mary’s Redwood Grove. “To start off, we had to find aphids,” said Hancock. “So, we went out into the Redwood Grove and literally just had baking sheets with paper in them, and we shook plants onto those to try and get aphids off plants in the wild. I think we started with maybe 30, and now we have all of these colonies. There's maybe between 500 to a thousand aphids in here now because they just proliferate and reproduce like nobody’s business.”

“During the second week of summer research, we began to collect plant samples from the same areas we found aphids,” added Cardinale. “This was so we could grind them up to create liquid substances out of them that we could apply to ELISA testing. ELISA testing shows through absorbance values if there's virus present or not through the plant samples that we initially collected. If we found BYDV [barley yellow dwarf virus] in the plant samples based on those data, then we could expose the aphids we collected to those plants so they could become carriers of BYDV to then expose them to our experimental plants (my drought-conditioned plants) to hopefully find a connection between drought and the dynamics of spread.”

The students were inspired by their mentor’s studies. “Dr. Blaisdell, our research mentor, has done a lot of research on a specific group of viruses that infect cereal crops, called barley yellow dwarf viruses, as well as the insects that carry these viruses, which are aphids,” said Hancock. “We’re mapping the behaviors of aphids that carry this virus and how different environmental conditions influence vector behavior, or how the plant grows in relation to the virus. With my research in particular, I’m trying to find safer alternatives to pesticides. This would prevent aphids from feeding on plants by using natural hormones that are already present in the plants’ defense mechanism.”

Cardinale is also deeply interested in climate change.“I wanted to make sure with my research that I brought awareness to a timely and important issue,” she said. “Even though the climate crisis is such a massive and deep issue to research, I believe that even trying to study and understand one aspect of it can help.”

The issue at hand: Our food supply. “I really wanted to look into the agricultural side of things and show how human civilization will be affected, all because of small creatures that are barely visible to the naked eye,” Cardinale continued. “By looking at how drought conditions caused by these rising temperatures influence aphid behavior and therefore virus spread and host plant stress, I am able to make connections to the larger picture at hand and begin to find ways to contribute to this area of research. I want to look into not only environmental impacts but economical and human health impacts as well.”

“The pesticides that we use right now, they're a safer alternative to stuff that we were using in the past called organophosphates, which are just so, so bad for you,” Hancock added. “But some research has pointed to these ‘safer’ alternatives still having potentially harmful impacts. This is pertinent to environmental health, human health—we eat barley and other cereal crops in cereal, bread, beer, all sorts of stuff. When we use pesticides, they accumulate in the soil and the water and we intake those. And so by finding safer alternatives using plant hormones, using materials that are already present in plants—hopefully, this would keep nasty toxins out of the environment and out of human bodies.”

Professor Blaisdell served as an enthusiastic mentor for this Summer Research Program, which draws upon her area of expertise. “In my research, I am generally interested in the interplay between vector-borne pathogens, insects, introduced species, and plant communities—both in unmanaged settings and in agriculture,” she said. “At Saint Mary’s College, I focus on two economically damaging plant viruses called barley stripe mosaic virus (BSMV) and barley yellow dwarf virus (BYDV) that affect cereal crops such as barley, oat, and wheat, and wild plants that are also in the grass family.” 

BSMV is spread mechanically through plant-to-plant contact and can be passed from parent plant through seed. BYDV is transmitted by aphids who feed on infected plants and then later on uninfected plants. 

Blaisdell applauds the research she’s watched both students undertake. “Emily and Emma each developed their own specific research goals within this broader framework, wrote research proposals, designed and conducted their experiments, analyzed their findings, and will present them through SRP’s Lightning Talks and Poster Session later this year,” Blaisdell said. “I have learned from each of them through their research; they have taken their focus in directions that are new to me.”

It will be a long process to determine whether the students found any virus in the Redwood Grove and other areas of campus they drew from, which includes 84 plant samples from around campus. 

“The most challenging part is just getting the virus in the lab because it shapes the way that we are doing research, what we're able to accomplish,” said Hancock. 

But both students still found the project valuable. “It’s really rewarding to just be part of scientific research and to feel like I can participate in science because sometimes science feels daunting or inaccessible,” said Hancock. “To be able to really engage with it and learn so much, like new techniques and ideas, and getting to be a part of it—I love it.”

Blaisdell also found the summer project rewarding. “I have learned from each of the students through their research; they have taken their focus in directions that are new to me. I value the continued opportunities to learn that are provided by research,” she said.

The Summer Research Program attracted Cardinale and Hancock to Saint Mary’s, and both hope to go into science-based careers after graduating. “I want to pursue research, definitely go to graduate school for anything in the biological field, and continue doing things that are pertinent to human health and environmental health,” said Hancock. “Before SRP I wasn’t sure exactly what I wanted to do, but having this experience has taught me that I really enjoy the research process and it is definitely something I can see myself doing in the future.”

Cardinale also has solid plans. “I have always been interested in radiology and am hoping to further my education in graduate school with the hopes of becoming a radiologist assistant. However, I have also become interested in public health and find those careers incredibly interesting. It is a broad field with a lot of opportunities in science. It'd be awesome to take some of my skills from the research program and apply them to future careers as well.”

Read more about SMC’s Summer Research Program.

Story updated June 6, 2023.