Identification and Observation of Infection Processes of Colletotrichum Species Associated with Pearl Plum Anthracnose in Guangxi, China

Abstract

Pearl plum (Prunus salicina Lindl.) is mainly cultivated in Tian’e County in Guangxi Province, southern China. Anthracnose is a devastating disease on pearl plum, causing extensive leaf blight. Diseased leaves were sampled from 21 orchards in Tian’e County. Isolates were first screened for ones resembling Colletotrichum, and 21 representative isolates were selected for sequencing of portions of the ribosomal internal transcribed spacer (ITS), the intergenic region of apn2 and MAT1-2-1 genes (ApMAT), actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), calmodulin (CAL), chitin synthase (CHS-1), and β-tubulin 2 (TUB2). Based on colony, conidial, and appressorial morphology and sequence analyses, the Colletotrichum isolates associated with pearl plum anthracnose were identified as four species: Colletotrichum fructicola (16 isolates), C. gloeosporioides (3 isolates), C. cigarro (1 isolate), and C. siamense (1 isolate). The results of pathogenicity tests showed that isolates of all four species were pathogenic to wounded leaves of pearl plum seedlings. In this study, we microscopically observed the infection processes of isolates of these four species on attached pearl plum leaves: for C. cigarro and C. siamense, the entire infection processes took 120 hours; for C. fructicola and C. gloeosporioides it only took 72 hours. This is the first report of C. fructicola and C. cigarro causing anthracnose on pearl plum worldwide, and also the first report of C. siamense causing anthracnose on pearl plum in China.

Species of the Colletotrichum spp., the Causal Agents of Leaf Spot on European Hornbeam (Carpinus betulus)

“…Due to its strong environmental adaptability, the Colletotrichum species can cause leaf spot and fruit diseases with huge losses in agricultural and forestry production worldwide [21,65,[73][74][75][76][77][78][79][80][81][82]. Furthermore, changes in the climate, human activities, and other factors may cause fungi host jumping within the plants in the nursery [83].…”

Screening and characterization of biocontrol bacteria isolated from Ageratum conyzoides against Collectotrichum fructicola causing Chinese plum (Prunus salicina Lindl.) anthracnose

“…Chinese plums are susceptible to a variety of diseases, including anthracnose, leaf spots, brown rot, shoot blight, bacterial shot-holes, and fruit blotching ( Long et al, 2021 ; Huang et al, 2022 ; Shu et al, 2022 ; Lu et al, 2022a , b ; Lei et al, 2023 ; Wen et al, 2023 ; Liu et al, 2023a , b ). Anthracnose is one of the most serious diseases resulting in destructive leaf blight in the pearl plum cultivar., in Guangxi, China ( Huang et al, 2022 ).…”

“…Colletotrichum fructicola is the dominant pathogenic species responsible for plum anthracnose ( Huang et al, 2022 ). This species was selected as the preliminary control target- indicator.…”

“…The production of Chinese plums can be negatively affected by various factors, including a range of diseases ( Long et al, 2021 ; Huang et al, 2022 ; Shu et al, 2022 ; Lu et al, 2022a , b ). Indeed, the Chinese plum is vulnerable to a variety of diseases, one of the most destructive of which is plum anthracnose, caused by the fungus Colletotrichum ( Huang et al, 2022 ). To date, C. fructicola , C. gloeosporioides , C. cigarro , C. siamense , and C .…”

“…To date, C. fructicola , C. gloeosporioides , C. cigarro , C. siamense , and C . aeschynomenes have been reported as the causative agents of plum anthracnose in China ( Huang et al, 2022 ; Lu et al, 2022a ). The pathogen mainly infects the leaves of the plum tree, generally manifesting as yellowish spots or lesions, followed by withering at later stages of the disease.…”