Tools for functional genomics are critical for understanding the biology of plant pathogens. This is especially true for the oomycete genus Phytophthora, which causes numerous devastating crop diseases. The infamous pathogen Phytophthora infestans, for example, is a limiting factor in potato production and can destroy fields in little more than a week (Leesutthiphonchai et al., 2018). Studies of P. infestans have shed light on oomycete metabolism, spore biology, and pathogenesis, thus helping to advance strategies for battling disease (Abrahamian