Desert Researcher Magazine Issue 1

BUGS WITHOUT BORDERS: PLANT VIRUSES IN THE WILDLAND-URBAN INTERFACE

By Susana Rinderle Did you know that plants can get viruses too? Plant-infecting viruses are no fun. From farmers to houseplant owners, many of us have done battle with such pests. While scientists have mainly studied these viruses in the context of agriculture, the insects that transmit them aren't bound by the artificial boundaries of human gardens or farms. In fact, wild plants are often hosts to crop-associated, insect-borne viruses. Studying wild plants can, therefore, provide insight into how viruses evolve, how viruses and host plants affect each other, and how human development impacts native species that we strive to protect.

Dr. Tessa Shates, PhD., an entomologist trained at the University of California at Riverside (UCR), set out to gain such insight by studying three wild plants and their domesticated cousins. She wanted to know: (1) What viruses are present in these wild plants, and how prevalent are they? (2) What are the impacts of virus infection?

Tessa and her co-authors combined field, laboratory, and greenhouse methods to find these answers. First, they sampled and monitored leaf tissue from the Motte Rimrock Reserve (University of California Natural Reserve System) and the Shipley-Skinner Multispecies Reserve in 2017. They focused on buffalo gourd, coyote melon, and sacred thorn-apple (sacred datura). In 2019, she was awarded the Howie Wier Memorial Conservation Grant from Anza-Borrego Foundation, which allowed her to expand the research to include Anza-Borrego Desert State Park (ABDSP).

They selected these wild plants for their similarities to crops. Buffalo gourd and coyote melon are in the same genus (Cucurbita) as squash, zucchini and pumpkins. Sacred thorn-apple is in the nightshade family (Solanaceae), which includes tomatoes, potatoes, eggplant and peppers.