Endophytic Colletotrichum (Sordariomycetes, Glomerellaceae) species associated with Citrus grandis cv. 'Tomentosa' in China

Colletotrichum species are well-known plant pathogens, saprobes, endophytes, human pathogens and entomopathogens. However, little is known about Colletotrichum as endophytes of plants and cultivars including Citrus grandis cv. “Tomentosa”. In the present study, 12 endophytic Colletotrichum isolates were obtained from this host in Huazhou, Guangdong Province (China) in 2019. Based on morphology and combined multigene phylogeny [nuclear ribosomal internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (gapdh), chitin synthase 1 (chs-1), histone H3 (his3) actin (act), beta-tubulin (β-tubulin) and glutamine synthetase (gs)], six Colletotrichum species were identified, including two new species, namely Colletotrichum guangdongense and C. tomentosae. Colletotrichum asianum, C. plurivorum, C. siamense and C. tainanense are identified as being the first reports on C. grandis cv. “Tomentosa” worldwide. This study is the first comprehensive study on endophytic Colletotrichum species on C. grandis cv. “Tomentosa” in China.