Submitted to: Fungal Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/13/2009
Publication Date: 11/1/2009
Citation: Vega, F.E., Simpkins, A., Aime, M., Posada, F., Peterson, S.W., Rehner, S.A., Infante, F., Castillo, A. 2009. Fungal endophyte diversity in coffee plants from Colombia, Hawaii, Mexico and Puerto Rico. Fungal Ecology. 3:122-138.
Interpretive Summary: The coffee berry borer is the most devastating pest of coffee throughout the world. Eggs are deposited inside coffee berries, and insects feed on the coffee seed, severely reducing yields. One novel mechanism to manage this insect involves studies aimed at inoculating coffee plants with the fungal insect pathogen Beauveria bassiana. As part of this research, we have conducted a survey of fungi naturally occurring inside coffee plants in Colombia, Hawaii, Mexico, and Puerto Rico. A total of 843 fungal samples were obtained and their DNA was sequenced, resulting in 257 unique sequences. These results reveal that coffee plants serve as a reservoir for a wide variety of fungi and suggest that it might be possible to have insect pathogenic fungi established inside coffee plants where they might have potential in biocontrol programs against the coffee berry borer. This finding will be of use to coffee scientists, mycologists, entomologists, and the coffee industry.
Technical Abstract: A survey of fungal endophytes in coffee plants was conducted in Colombia, Hawaii, Mexico and Puerto Rico. Coffee plant sections were sterilized and fungal endophytes were isolated using standard techniques, followed by DNA extraction and sequencing of the internal transcribed spacer region (ITS) of the nuclear rDNA. A total of 843 fungal isolates were isolated as follows: Colombia 267; Hawaii 395; Mexico 108; and Puerto Rico 73. These endophytes yielded 257 unique sequences with the following number of species/phylotypes: Colombia 111; Hawaii 125; Mexico 32; and Puerto Rico 39. The most common endophytes were Colletotrichum (40 phylotypes), Fusarium (25 phylotypes), Penicillium (14 phylotypes and 11 species), and Xylariaceae (26 phylotypes). Only 3 identical endophyte sequences (Colletotrichum 21, Fusarium 18, and Penicillium 9) were shared between Colombia, Hawaii, Mexico and Puerto Rico and out of the 257 unique sequences, 220 were detected in only one of the “countries” sampled. Fungal endophytes were also isolated from C. canephora, C. congensis, C. liberica, C. macrocarpa, C. racemosa, and C. stenophylla growing in Hawaii. These results demonstrate that coffee plants serve as a reservoir for a wide variety of fungal endophytes whose role, if any, deserves further study.