Submitted to: Mycologia
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/19/2005
Publication Date: 6/15/2006
Citation: Vega, F.E., Posada, F.J., Peterson, S.W., Gianfagna, T.J., Chaves, F. 2006. Penicillium species endophytic in coffee plants and ochratoxin a production. Mycologia. 98:31-42. Interpretive Summary: Fungi in the genus Penicillium, known to produce a wide range of chemical substances, are known to live inside plant tissues. We isolated 13 Penicillium species living inside coffee tissues (roots, leaves, stems and berry) and have tested them for production of a toxic compound known as ochratoxin A, whose presence in coffee beans is a problem for the coffee industry. Only four of the Penicillium isolates produced ochratoxin A, although at extremely low levels. This information will be of use to coffee scientists, mycologists, and the coffee industry.
Technical Abstract: Tissues from Coffea arabica, C. liberica, C. dewevrei and C. congensis collected in Hawaii, Colombia and at a local plant nursery in Maryland were sampled for the presence of fungal endophytes. Surface sterilized tissues including roots, leaves, stems, and various part of the berry were plated on yeast malt agar. DNA was extracted from a set of isolates visually recognized as Penicillium and the internal transcribed spacer region and partial LSU-rDNA was amplified and sequenced. Comparison of DNA sequences with GenBank and unpublished sequences revealed the presence of ten known Penicillium species: P. brevicompactum, P. brocae , P. citrinum, P. coffeae, P. crustosum, P. janthinellum, P. olsonii, P. oxalicum, P. sclerotiorum and P. steckii, as well as three possibly undescribed species near P. dendriticum, P. diversum, and P. roseopurpureum. Ochratoxin A production was positive in only four isolates, one isolate each of P. brevicompactum, P. crustosum, P. olsonii, and P. oxalicum. The role that these endophytes play in the biology of the coffee plant remains enigmatic.