Colletotrichum species associated with anthracnose of Pyrus spp. in China

Abstract

Colletotrichum species are plant pathogens, saprobes, and endophytes on a range of economically important hosts. However, the species occurring on pear remain largely unresolved. To determine the morphology, phylogeny and biology of Colletotrichum species associated with Pyrus plants, a total of 295 samples were collected from cultivated pear species (including P. pyrifolia, P. bretschneideri, and P. communis) from seven major pear-cultivation provinces in China. The pear leaves and fruits affected by anthracnose were sampled and subjected to fungus isolation, resulting in a total of 488 Colletotrichum isolates. Phylogenetic analyses based on six loci (ACT, TUB2, CAL, CHS-1, GAPDH, and ITS) coupled with morphology of 90 representative isolates revealed that they belong to 10 known Colletotrichum species, including C. aenigma, C. citricola, C. conoides, C. fioriniae, C. fructicola, C. gloeosporioides, C. karstii, C. plurivorum, C. siamense, C. wuxiense, and two novel species, described here as C. jinshuiense and C. pyrifoliae. Of these, C. fructicola was the most dominant, occurring on P. pyrifolia and P. bretschneideri in all surveyed provinces except in Shandong, where C. siamense was dominant. In contrast, only C. siamense and C. fioriniae were isolated from P. communis, with the former being dominant. In order to prove Koch's postulates, pathogenicity tests on pear leaves and fruits revealed a broad diversity in pathogenicity and aggressiveness among the species and isolates, of which C. citricola, C. jinshuiense, C. pyrifoliae, and C. conoides appeared to be organ-specific on either leaves or fruits. This study also represents the first reports of C. citricola, C. conoides, C. karstii, C. plurivorum, C. siamense, and C. wuxiense causing anthracnose on pear.

Emergence of Benzimidazole- and Strobilurin-Quinone Outside Inhibitor-Resistant Strains ofColletotrichum gloeosporioidessensu lato, the Causal Fungus of Japanese Pear Anthracnose, and Alternative Fungicides to Resistant Strains

“…pathogens causing anthracnose on pear leaves and fruit [17]. In Japan, we did not confirm anthracnose symptoms on Japanese pear fruit caused by Cgsl.…”

Diversity and pathogenicity of Colletotrichum species causing strawberry anthracnose in Taiwan and description of a new species, Colletotrichum miaoliense sp. nov.

“…acutatum species complex, 3 isolates together with 40 reference isolates, including the outgroup C . orchidophilum (CBS 632.80), were used to construct phylogenetic trees with five gene sequences (ITS, GAPDH , CHS-1 , ACT , and TUB2 ) (Table 1 and Supplementary Table S1 ) following Damm et al 12 and Fu et al 20 . The final data matrix contained a total of 1,821 characters with gaps (ITS: 1–540, GAPDH : 541–799, CHS-1 : 800–1,081, ACT : 1,082–1,329, TUB2 : 1,330–1,821), of which 237 characters were parsimony informative, 174 parsimony uninformative, and 1,410 constant.…”

“…The fitness advantage of C. siamense in warm temperature weather may explain its current geographical distribution. In the literature, C. siamense was most reported in tropical and subtropical regions 13,16,38 , whereas C. boninense, C. fructicola, and C. karstii were reported in regions across a wide range of latitudes 13,20,21,33,[39][40][41] . Temperature is among the key environmental factors affecting a pathogen's survival 42 .…”

“…siamense was most reported in tropical and subtropical regions 13 , 16 , 38 , whereas C. boninense , C. fructicola , and C . karstii were reported in regions across a wide range of latitudes 13 , 20 , 21 , 33 , 39 – 41 . Temperature is among the key environmental factors affecting a pathogen’s survival 42 .…”

Morphology, DNA Phylogeny, and Pathogenicity of Wilsonomyces carpophilus Isolate Causing Shot-Hole Disease of Prunus divaricata and Prunus armeniaca in Wild-Fruit Forest of Western Tianshan Mountains, China

“…Mycelial discs of the 25 isolates were transferred to PDA plates covered with sterile cellophane and incubated at 25 • C in a 12 h photoperiod for 6 d [40]. Total DNA was extracted using the modified CTAB (cetyl trimethyl ammonium bromide; known as cetrimonium bromide) method [41].…”