Cryptic Species: A Leitmotif of Contemporary Mycology Has Challenges and Benefits for Plant Pathologists

Abstract

Multiple traditional species names for plant pathogenic fungi have been supplemented with new names that delimit formerly cryptic species. In separate instances, isolates within a species are clearly differentiated by both phylogeny and distinctive pathogenic traits and are assigned sub-specific designations. These new species names and the sub-specific designations are both cases of cryptic species that are, in some instances, relevant and/or critical for plant disease management. Here we provide examples of such instances in which newly described taxa differ from the original ("parent") in phenotypic traits of importance to plant disease management: host range, fungicide sensitivity, environmental niche, metabolite production, regulatory status, or other attributes.

Biological Control of Botrytis cinerea: Interactions with Native Vineyard Yeasts from Washington State

“…In addition, the colony morphology of isolate R1V55#13 on KMB, APDA, and PAM was similar to that of B. prunorum from Chile (Ferrada et al 2016) and different from the Washington B. cinerea isolates. To the best of our knowledge, isolate R1V55#13 may be the first report of B. prunorum from grape and it exemplifies recent differences in host preference, disease phenotype, and morphology among the B. cinerea isolates that formed the bases for new species (Dugan 2016;Walker 2016). Overall, this diversity suggests that the Washington population of B. cinerea comprises several to many genotypes, and perhaps is part of a Botrytis complex.…”

Improving Taxonomic Delimitation of Fungal Species in the Age of Genomics and Phenomics

“…Often termed “cryptic species,” this moniker highlights that species boundaries in fungi are not always clearly defined ( Bickford et al, 2007 ). Fusarium subglutinans , which has more than 20 individuals described as part of the species complex, is a group of well documented plant pathogens demonstrating similar morphology, but distinct biological, ecological, and phylogenetic relationships ( Dugan and Everhart, 2016 ). Similarly, recent evidence shows that Fusarium species causing Fusarium Head Blight disease in wheat and other grains are capable of shifting geographic ranges or altering mycotoxin production, which poses a significant challenge to crop yields worldwide ( Valverde-Bogantes et al, 2020 ).…”

Catalog of Penicillium spp. causing blue mold of bulbs, roots, and tubers

“…Previously attributed to a small number of Penicillium species, blue mold pathogens on bulb and root crops have been assigned by modern moleculargenetic methods to an increasing number of species, many of which represent "cryptic" species segregated from other species described decades ago (Dugan & Everhart 2016). In comparing sets of investigations, results from artificial inoculations reveal substantial areas where host ranges agree as well as instances with contradictory results (Dugan & al.…”