Distribution and Characteristics of Colletotrichum spp. Associated with Anthracnose of Strawberry in Hubei, China

Abstract

Anthracnose caused by Colletotrichum spp. is a serious disease of strawberry. The etiology of anthracnose of strawberry is complex, and several Colletotrichum spp. have been regarded as causal agents. In the present study, multilocus (actin, β-tubulin, calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase) phylogenetic analysis revealed that 100 isolates of Colletotrichum associated with anthracnose of strawberry in central China belong to five species. In total, 97 isolates were identified belonging to the Colletotrichum gloeosporioides species complex, with C. murrayae, C. gloeosporioides, C. fructicola, and C. aenigma accounting for 81, 8, 4, and 4% of the total isolates, respectively. Three isolates belonging to the C. acutatum complex were identified as C. nymphaeae. On inoculated strawberry plants, isolates of C. fructicola and C. murrayae species showed strong pathogenicity to both leaves and petioles of strawberry, with plant mortality 30 days after inoculation of 77.8 and 55.6%, respectively. C. gloeosporioides, C. aenigma, and C. nymphaeae showed strong pathogenicity to leaves but weak pathogenicity to petioles, with plant mortality 30 days after inoculation of 5.6, 16.7, and 11.1%, respectively. The five species were divided into four classes based on their maximum growth temperatures. Isolates of C. murrayae and C. gloeosporioides were more tolerant to high temperature (>34°C) than isolates of other species, followed by C. fructicola and C. aenigma. Isolates of C. nymphaeae, which are only distributed in areas of higher altitude (1,100 m), were highly sensitive to higher temperature. These results indicate that pathogenicity and adaptation to temperature are important factors in the distribution of Colletotrichum spp. on strawberry plants. This research may increase our understanding of how Colletotrichum spp. emerge and spread to geographical regions with different latitudes or elevations.

Carbendazim sensitivity in populations of Colletotrichum gloeosporioides complex infecting strawberry and yams in Hubei Province of China

“…Monoconidial cultures were subsequently obtained through serial dilution, and isolates without conidia on the PDA plates were purified by transferring samples from the advancing mycelial edge of each colony to new PDA plates three to five times. All Colletotrichum isolates were identified to the species using a multilocus phylogenetic analysis identification method (Han et al 2016).…”

“…The mycelia of each isolate were ground to a fine powder in liquid nitrogen with a mortar and pestle. Genomic DNA (gDNA) was extracted and purified by using a previously published protocol (Han et al 2016). Purified DNA was dissolved in 200 μL of TE buffer (10 mmol L -1 Tris-HCl, 1 mmol L -1 EDTA, pH 8.0), and diluted to approximately 10 to 100 ng μL -1 for polymerase chain reaction (PCR).…”

“…For sequence analysis, TUB2 genes were amplified from gDNA of Colletotrichum isolates with primers in Table 1. The DNA of TUB2 was amplified in two parts: part 1 (fragment size, 870 bp) of the TUB2 gene was amplified with primer pair T1 (O'Donnell and Cigelnik 1997) and TUB2-R2 (Han et al 2016), and part 2 (fragment size, 1 328 bp) of the TUB2 gene was amplified with primer pair TUB2-F3 and TUB2-R4 (Table 1). The primers TUB2-R2 (part 1), TUB2-F3 (part 2) and TUB2-R4 (part 2) were used for sequencing.…”

“…Strawberry infected with Colletotrichum species may develop lesions on all parts of plants, resulting in the collapse and death of the plant in serious cases (Freeman et al 1998). The etiology of strawberry anthracnose is complex, and 12 Colletotrichum species have been regarded as causal agents (Weir et al 2012;Han et al 2016). In a preliminary study, Colletotrichum siamense (in synonymy with Colletotrichum murrayae) (Liu et al 2016), Colletotrichum fructicola, Colletotrichum gloeosporioides, and Colletotrichum aenigma in C. gloeosporioides complex were identified to cause anthracnose on strawberry in Hubei Province of China.…”

“…C. gloeosporioides and C. aenigma showed weak virulence to petioles. C. siamense was the most frequently isolated species, accounting for 81% of all isolates (Han et al 2016).…”