Colletotrichum parallelophorum X.Y. Ma, K.D. Hyde & Jayawardena

Ma, Xiaoya, Nontachaiyapoom, Sureeporn, Jayawardena, Ruvishika S., yde, Kevin D., Gentekaki, Eleni, Zhou, Sixuan, Qian, Yixin, Wen, Tingchi & Kang, Jichuan, 2018, Endophytic Colletotrichum species from Dendrobium spp. in China and Northern Thailand, MycoKeys 43, pp. 23-57 : 33-36

Colletotrichum parallelophorum X.Y. Ma, K.D. Hyde & Jayawardena sp. nov. Figure 6

Etymology.

In reference to the parallel conidiophores.

Holotype.

MFLU 17-1198 (ex-holotype culture: MFLUCC 14-0083).

Description.

Asexual morph on CMA. Vegetative hyphae 2-4.3 µm diam (N=30), smooth-walled, septate, branched, hyaline to pale brown. Chlamydospores not ob served. Conidiomata acervular, orange. Appressoria (56.7-) 60.2-79.2 (-81.2) × (2.8-) 2.9-3.7 (-3.9) µm (N=8), single, sub-globose, brown, rare. Conidiophores and setae formed on a cushion of pale brown cells (1.9-) 2.4-4 (-4.6) µm diam. Setae medium brown, smooth-walled, 2 or 3-septate; base cylindrical, constricted at the base, apex acute. Conidiophores (18.3-) 20.8-34 (-41.2) × (2.6-) 2.8-4.3 (-5.4) µm (N=20), smooth-walled, 2 to 3-septate, branched, hyaline to pale brown. Conidiophores and setae formed on a cushion of pale brown prismatic cells, sometimes with guttules. Conidia (12.1-) 13.8-16.8 (-18.9) × (3.3-) 4.4-7.5 (-7.9) µm (N=50), L/W = 2.6, hyaline, smooth-walled, with 1 to 4 guttules, cylindrical with both ends rounded.

Sexual morph on CMA. Ascomata (267-) 261.4-342.3 (-346.2) × (190.4-) 173.0-272.5 (-280) µm (N=3), globose, glabrous, Ascomata isolated, scattered, irregular and asymmetrical, black. Peridium 13.6-46.4 µm thick, consist of pale to medium brown flattened angular cells. Ascogenous hyphae hyaline, smooth-walled. Asci (43.3-) 44.1-63.3 (-66.5) × (7.6-) 8.0-9.8 (-10) µm (N=7), cylindrical, straight, unitunicate, 8-spored. Ascospores (13.9-) 14.1-18 (-20.9) × (3.1-) 3.9-5.4 (-5.8) µm (N=23), L/W = 3.5, uni-to bi-seriately, aseptate, smooth-walled, ellipsoidal, single guttules in the middle, both ends rounded, hyaline.

Cultures on CMA flat with entire margin. Growth rate: 0.4cm/d, with 20-days for sporulation. With fluffy, light green and white mycelia. Ascomata sometimes growing together with acervuli.

Material examined.

Thailand, Chiang Rai, Wat Phra That Doi Tung (Temple of Doi Tung Pagodas), the host Dendrobium sp. 1 was collected on 19 December 2013, Collector: Sureeporn Nontachaiyapoom, Natdanai Aewsakul, Xiaoya Ma.

Notes.

Strains MFLUCC 14-0077, MFLUCC 14-0079 and MFLUCC 14-0083 had identical sequence data and they formed a single clade with MFLUCC 14-0082 and MFLUCC 14-0085. They are closely related to Colletotrichum excelsum-altitudum and C. tropicicola . MFLUCC 14-0077, MFLUCC 14-0079, MFLUCC 14-0082, MFLUCC 14-0083 and MFLUCC 14-0085 have similar morphological characteristics. Therefore, the five strains are regarded as the same species. There were totally 103bp and 101bp differences between MFLUCC 14-0083 and C. excelsum-altitudum / C. tropicicola respectively (mainly in GAPDH). Blastn researches with four-gene sequences of five strains presented 99% identity with ITS sequence of C. cordylinicola strain LC0886, 80% identity with GAPDH (GenBank JN050229), 90% identity with ACT (GenBank JN050218) and 93% identity with TUB2 (GenBank JN050246) sequences of C. tropicola strain LC0598 respectively as mentioned above. Conidia size and shape were very similar among MFLUCC 14-0083, C. excelsum-altitudum and C. tropicicola . Appressoria were rare and in strain MFLUCC–14– 0083 appressoria were not variable like that in C. excelsum-altitudum and C. tropicicola . Here we introduced strains MFLUCC 14-0077, MFLUCC 14-0079, MFLUCC 14-0082 and MFLUCC 14-0083 and MFLUCC–14– 0085 isolated from stems and roots of Dendrobium sp. 1 as Colletotrichum parallelophorum sp.nov.