A multigene phylogeny reveals the occurrence of fourteen dominant Penicillium species in India

Penicillium contains 483 accepted species worldwide but the occurrence of predominant species in India is still unknown. Therefore, 35 isolates of 15 different states of India were procured from Indian Type Culture Collection (ITCC), New Delhi. All these isolates were made into eight species of Penicillium viz., "P. aethiopium", "P. chrysogenum", "P. crustosum", "P. mononematosum", "P. oxalicum", "P. polonicum", "P. singorense", "P. spinulosum" and one species of "Talaromyces pinophilus" based on morphology and multigene analysis comprises ITS, cal, rpb2 and beta-tub genes. Phylogenetic analyses using these sequences through maximum parsimonious method showed beta-tub gene as a potential region for DNA barcoding to differentiate the species of Penicillium with maximum inter population diversity (2.15), coefficient of differentiation (8.54), barcode gap (1.93) and probability of correct identification (0.081) and it can be used as secondary barcode apart from ITS as universal primary barcode. The beta-tub gene was also validated using six more species of Penicillium (P. canescens, P. daleae, P. janthinillum, P. ochrochloron, P. simplicissimum and P. vasconiae) isolated from soils of Delhi and Meghalaya states, where all the species showed clear differentiation from one another. In conclusion, fourteen predominant Penicillium species was established through morpho-molecular approach and three Penicillium species (P. mononematosum, P. singorense and P. vasconiae) were reported first time from India and beta-tub sequence-based identification was the best to confirm the morphological based identification.