Recently described species Penicillium psychrotrophicum as postharvest fungal pathogen of garlic bulbs in Serbia

Garlic (Allium sativum L.) is one of the most signi cant plants from the Amaryllidaceae, used in culinary practices, traditional and modern medicine. During storage, garlic bulbs can become rotten due to postharvest plant pathogens. e objective of our research was to isolate and identify Penicillium species from garlic bulbs with the symptoms of blue mold, collected in 2022 from storages in Serbia (around Pančevo, Kragujevac and Leskovac). e isolates were identi ed using conventional and molecular methods. Macromorphology was examined on Czapek yeast autolysate agar (CYA), Malt extract agar (MEA) and Creatine sucrose agar (CREA) incubated at 25°C, and on CYA at two additional incubation temperatures (5 and 37°C). Four genetic loci were sequenced: internal transcribed spacer (ITS), beta tubulin (TUB2), calmodulin (CMD) and RNA polymerase II second largest subunit (RPB2). Symptoms on the collected bulbs were so, watery tissue, with presence of white mycelia and blue-green fungal spores. e isolates had moderate growth on tested media (CYA 32.58 mm; MEA 30.17 mm; CREA 11.00 mm). Radially sulcate colonies with velvety texture and green spores were noticed on CYA, and compact colonies with fasciculate texture on MEA. Strong acid production was noticed on CREA medium. e isolates exhibited growth at 5°C and no growth was observed at 37°C. Under the microscope, the fungi had terveticillate conidiophores, with ovoidal to fusiform spores, 2.50 × 3.50 μ (the average diameter), and nely roughened cell walls. Aer combining the results of all assays, the isolates were identi ed as Penicillium psychrotrophicum. In pathogenicity test this species was con rmed as a pathogen of garlic bulbs. P. psychrotrophicum is a recently described species, isolated from the roots of Codonopsis lanceolata (deodeok) in South Korea. Our nding is the only detection of this fungi aer the initial description, contributing with new data about its biology and ecology.