Endophytic Colletotrichum species from Dendrobium spp. in China and Northern Thailand Author Ma, Xiaoya Author Nontachaiyapoom, Sureeporn Author Jayawardena, Ruvishika S. Author yde, Kevin D. Author Gentekaki, Eleni Author Zhou, Sixuan Author Qian, Yixin Author Wen, Tingchi Author Kang, Jichuan text MycoKeys 2018 43 23 57 http://dx.doi.org/10.3897/mycokeys.43.25081 journal article http://dx.doi.org/10.3897/mycokeys.43.25081 1314-4049--23 Colletotrichum orchidophilum Damm, P.F. Cannon & Crous Figure 10 Description . Sexual morph not observed. Sexual morph not observed. Asexual morph on SDA. Vegetative hyphae 1.9-5.4 µm diam, smooth-walled, septate, branched, hyaline to pale brown. Chlamydospores not observed. Appressoria brown, smooth-walled. Conidiomata superficial or under mycelia, smooth-walled, 200 x 300 µm , black. Conidiophores smooth-walled, branched or unbranched, hyaline. Conidiophores and appressoria rare. Conidia (9.6-) 11.7-14.1 (-14.7) x (2.9-) 3.5-4.4 (-4.8) µm , L/W = 3.3, cylindrical, straight, with 1 to 4 guttules, one end somewhat acute, hyaline. Cultures on SDA flat with entire margin. Growth rate: 0.44cm/day, with nearly 20-days for sporulation. White with dark green mycelia around the middle, white edge, reverse white. Cultures on PDA flat with entire margin. Growth rate: 0.45cm/day, with 30-days for sporulation. Fluffy, white, reverse light brown. Acervuli in mass black, irregular, asymmetrical, merging in media. Figure 10. Colletotrichum orchidophilum. A Colony B Fruiting body C-D Conidiophores E Appressoria F-K Conidia. Scale bars: 200 µm (B), 5 µm ( F-K ). Notes. Strains MFLUCC-14- 0161 and MFLUCC-14- 0162 belong to a single species as they have similar conidia, cultures and the nearly identical sequence data. The support values of 100/1.00/100 totally grouped them with C. orchidophilum and their branch lengths are slightly different. Blastn researches sequences of MFLUCC 14-0161 and MFLUCC 14-0162 results in 99% identity with ITS (GenBank NR111729), GAPDH (GenBank JQ948481) and ACT (GenBank JQ949472) sequences of ex-holotype culture of C. orchidophilum strain CBS 632.80 isolated form Dendrobium sp. in USA (Damm et al. 2012). TUB2 sequence is 99% identity with pathogenic C. fructicola strain AV24 (GenBank KX786459) isolated from grapevine shoots in Brazil (Santos et al. 2018) and C. gloeosporioides strain TL-2 (GenBank KC913205) isolated from Camellia sinensis in China ( Guo et al. 2014 ). Because no conidiophores were detected in culture, no measurement for the conidiophores could be given. In this study, strains MFLUCC 14-0161 and MFLUCC 14-0162 of C. orchidophilum were isolated from leaves of D. harveyanum .