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High tunnels extend the growing season of high value crops, including tomatoes, but the environmental conditions within high tunnels favor the spread of the tomato leaf mold pathogen, Passalora fulva (syn. Cladosporium fulvum ). Tomato leaf mold results in defoliation, and if severe, losses in yield. Despite substantial research, little is known regarding the genetic structure and diversity of populations of P . fulva associated with high tunnel tomato production in the United States. From 2016 to 2019, a total of 50 P . fulva isolates were collected from tomato leaf samples in high tunnels in the Northeast and Minnesota. Other Cladosporium species were also isolated from the leaf surfaces. Koch's postulates were conducted to confirm that P . fulva was the cause of the disease symptoms observed. Race determination experiments revealed that the isolates belonged to either race 0 (six isolates) or race 2 (44 isolates). Polymorphisms were identified within four previously characterized effector genes: Avr2 , Avr4 , Avr4e , and Avr9 . The largest number of polymorphisms were observed for Avr2 . Both mating type genes, MAT1 - 1 - 1 and MAT1 - 2 - 1 , were present in the isolate collection. For further insights into the pathogen diversity, the 50 isolates were genotyped at 7,514 single-nucleotide polymorphism loci using genotyping-by-sequencing. Differentiation by region but not by year was observed. Within the collection of 50 isolates, there were 18 distinct genotypes. Information regarding P . fulva population diversity will enable better management recommendations for growers, as high tunnel production of tomatoes expands.

Cladosporium species are ubiquitous, saprobic, dematiaceous fungi, only infrequently associated with human and animal opportunistic infections. We have studied a large set of Cladosporium isolates recovered from clinical samples in the United States to ascertain the predominant species there in light of recent taxonomic changes in this genus and to determine whether some could possibly be rare potential pathogens. A total of 92 isolates were identified using phenotypic and molecular methods, which included sequence analysis of the internal transcribed spacer (ITS) region and a fragment of the large subunit (LSU) of the nuclear ribosomal DNA (rDNA), as well as fragments of the translation elongation factor 1 alpha (EF-1α) and actin (Act) genes. The most frequent species was Cladosporium halotolerans (14.8%), followed by C. tenuissimum (10.2%), C. subuliforme (5.7%), and C. pseudocladosporioides (4.5%). However, 39.8% of the isolates did not correspond to any known species and were deemed to comprise at least 17 new lineages for Cladosporium. The most frequent anatomic site of isolation was the respiratory tract (54.5%), followed by superficial (28.4%) and deep tissues and fluids (14.7%). Species of the two recently described cladosporiumlike genera Toxicocladosporium and Penidiella are reported for the first time from clinical samples. In vitro susceptibility testing of 92 isolates against nine antifungal drugs showed a variety of results but high activity overall for the azoles, echinocandins, and terbinafine., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)