PCR-Based Detection and Characterization of the Fungal Pathogens Colletotrichum gloeosporioides and Colletotrichum capsici Causing Anthracnose in Papaya (Carica papaya L.) in the Yucatan Peninsula (original) (raw)
Related papers
Molecular Biotechnology, 2011
Colletotrichum capsici is an important fungal species that causes anthracnose in many genera of plants causing severe economic losses worldwide. A primer set was designed based on the sequences of the ribosomal internal transcribed spacer (ITS1 and ITS2) regions for use in a conventional PCR assay. The primer set (CcapF/ CcapR) amplified a single product of 394 bp with DNA extracted from 20 Mexican isolates of C. capsici. The specificity of primers was confirmed by the absence of amplified product with DNA of four other Colletotrichum species and eleven different fungal genera. This primer set is capable of amplifying only C. capsici from different contaminated tissues or fungal structures, thereby facilitating rapid diagnoses as there is no need to isolate and cultivate the fungus in order to identify it. The sensitivity of detection with this PCR method was 10 pg of genomic DNA from the pathogen. This is the first report of a C. capsici-specific primer set. It allows rapid pathogen detection and provides growers with a powerful tool for a rational selection of fungicides to control anthracnose in different crops and in the post-harvest stage.
Molecular Biotechnology, 2012
Anthracnose caused by Colletotrichum gloeosporioides is an economically important disease which affects greater yam (Dioscorea alata L.) worldwide. Apart from airborne conidia, the pathogen propagules surviving in soil and planting material are the major sources of inoculum. A nested PCR assay has been developed for specific detection of C. gloeosporioides in soil and planting material. In conventional (single-round) PCR, the limit of detection was 20 pg, whereas in nested PCR the detection limit increased to 0.2 pg of DNA. The primers designed were found to be highly specific and could be used for accurate identification of the pathogen up to species level. The protocol was standardized for detection of the pathogen in artificially and naturally infected field samples.
European Journal of Plant Pathology, 2013
Recently, anthracnose has become a major problem in papaya production and postharvest stages. The occurrence of both Colletotrichum gloeosporioides and Colletotrichum capsici has been demonstrated in this crop. The differential response of these pathogens to fungicides has highlighted the need to use rapid and accurate techniques to identify them. Thus, the objective of this study was to reveal the genetic diversity of Colletotrichum isolates in Mexican papaya fields. C. gloeosporioides-and C. capsicispecific primers were successfully used to detect the pathogens from different papaya parts. A combination of morphological characters, molecular techniques and pathogenicity tests were used to characterize 37 isolates from different localities of five papaya-producing states. Analyses of the 5.8-ITS region and arbitrarily primed-PCR revealed intraspecific groups; most of the isolates within these groups have the same geographical location and morphological characteristics. Knowledge of the genetic diversity of Colletotrichum spp. in Mexican papaya fields will facilitate the identification of the pathogen population in this crop in order to select the appropriate fungicide to control anthracnose, as well as to improve genetic resistance breeding programs.
Journal of Root Crops, 2015
Greater yam is an important species of yam grown in different parts of India. Anthracnose or die back disease caused by Colletotrichum gloeosporioides reduces the yield up to 90 per cent. The pathogen survives in the soil debris and transmits the disease to the next season through tubers. In this study, a sensitive method for the specific diagnosis of C. gloeosporioides in soil and planting material was developed. The standard nested PCR previously described was re-standardized to run a single nested PCR in a closed tube. The problems of cross contamination and the increased risk of PCR product contamination, while handling the product of first PCR could be avoided. This technique could be achieved by adjusting the concentration of primers and the annealing temperature along with the standardization of PCR cycles so as to produce a single amplicon without compromising the limit of detection and specificity. The lowest amount of DNA that could be determined by this method was 200 pg ...
Indian Journal Of Agricultural Research, 2021
Background: Anthracnose disease caused by the genus Colletotrichum is one of the crucial problems occurring in the field, along with postharvest diseases and affects mango quality in Thailand. In particular, the Nam Dork Mai See Tong cultivar, which is highly susceptible to the disease, is an important product for exportation. Methods: In this research, thirty-seven Colletotrichum species isolate were obtained from anthracnose disease in mango cv. Nam Dork Mai See Tong in three provinces in Thailand. Morphological studies and molecular techniques using species-specific primers were investigated; moreover, the diversity of pathogens was analyzed using PCR amplification of inter simple sequence repeats (ISSRs) with 6 primers, including pathogenicity tests. Result: Morphological studies and molecular detection with species-specific primers revealed that 32 isolates belonged to the C. gloeosporioides species complex and 5 isolates to the C. acutatum species complex. The genetic diversit...
Anthracnose, caused by the fungus Colletotrichum gloeosporioides, is one of the most important diseases in cashew (Anacardium occidentale) cultivation. In this study, the genetic and pathogenic diversity of this microorganism isolated from cashew crops from Pernambuco State, Brazil, were evaluated by RAPD and ribosomal DNA-RFLP analysis. Based on the RAPD analysis, considerable genetic diversity was exhibited by the evaluated isolates, and the rDNA RFLP analysis by MspI restriction demonstrated polymorphisms among the isolates. Although both techniques were efficient and reproducible, RAPD indicated higher genetic variability among the isolates when compared with the rDNA RFLP analysis. The isolates were clustered in two groups using UPGMA analysis of the RAPD and RFLP data, with Group I subdivided into five subgroups and Group II into four subgroups. A pathogenicity test performed using detached cashew leaves showed that the isolates Cg02 and Cg03 were the most aggressive. Through RAPD and rDNA RFLP analyses, this study demonstrated a correlation between the genetic groups and geographical origin of the isolates; however, no correlation was found between these groups and pathogenicity. 251 rRNA gene, which involves an adjusted model showing a small specific polymorphism and a high general specific variability . The amplification of this region and its restriction is an important tool to describe the genetic variability of plant pathogenic fungi. This study aimed to evaluate the genetic variability of C. gloeosporioides isolates obtained from cashew trees in different regions of Pernambuco State, Brazil, using RAPD and rDNA-RFLP analysis and to determine the possible correlation between the region and pathogenicity level of the isolates.
Plant Pathology, 2009
Real-time PCR (TaqMan®) assays were developed for the specific detection and discrimination of Colletotrichum spp., C. acutatum and C. gloeosporioides causing anthracnose in strawberry using the most divergent area of the internal transcribed spacers (ITS1 and ITS2) and 5·8S ribosomal RNA (rRNA) gene region. The specificity of the new assays was tested using DNA from six species of Colletotrichum and nine fungal species commonly found associated with strawberry material, and additionally by comparing the sequences with those from databases using a blast search. The sequences only showed identity with homologous sequences from the desired target organisms. The new assays were 10-100 times more sensitive than conventional PCR methods previously published for the diagnosis of strawberry anthracnose. When real-time PCR was compared with ELISA methods, PCR improved the sensitivity of the identification by obtaining positive results for samples of strawberry plant material that tested negative with ELISA. The development of C. acutatum was monitored using artificially infected strawberry crowns from two strawberry cultivars (Camarosa and Ventana) and a real-time PCR assay specific for this species between January and June 2006. The amount of C. acutatum detected using real-time PCR varied significantly by month ( P < 0·001), but not by cultivar ( P = 0·394). The new assays were shown to be useful tools for rapid detection and identification of these pathogens and to allow rapid and accurate assessment of the casual agents of anthracnose in strawberry.
First Report of Colletotrichum chrysophilum Causing Papaya Anthracnose in Mexico
Plant Disease
Anthracnose, caused by Colletotrichum spp., is the most important fungal disease of papaya (Carica papaya L.) worldwide. In March 2020, mature papaya fruit (cv. Maradol) showing typical symptoms of anthracnose were observed in an orchard located in Pinotepa Nacional, Oaxaca, Mexico. Disease incidence of 100 papaya plants surveyed in the orchard was estimated at about 45%. Initially, small and water-soaked lesions appeared on the fruit surface, which later enlarged to circular sunken lesions with translucent light brown margins. On advanced infections, salmon-pink masses of spores were observed on the lesions. Twenty Colletotrichum-like colonies were consistently isolated on potato dextrose agar (PDA) medium at 25°C in the dark for 6 days and 10 monoconidial isolates were obtained. An isolate was selected as representative for further characterization. The isolate was deposited as CPM-H4 in the Culture Collection of Phytopathogenic Fungi of Plant Pathology Laboratory of the CIIDIR-Oa...
Post-harvest anthracnose of papaya caused by Colletotrichum truncatum in Korea
In October 2016, we collected samples of post-harvest anthracnose of papaya from Gangneung, Gangwon Province, Korea. Infected fruits first showed tiny light brown spots on their surface followed by development of sunken water-soaked lesions with black acervuli. Fungal pathogen was isolated from the infected fruits and cultured on potato dextrose agar (PDA) and synthetic nutrient agar (SNA) medium. For identification of the fungus, morphological assessment and sequencing analysis of 5.8S ribosomal DNA (ITS-5.8S rDNA) and three protein-coding genes: actin (ACT), chitin synthase I (CHS-1), and glyceraldehyde-3- phosphate dehydrogenase (G3PDH) were performed. Pathogenicity of the fungal isolate was confirmed according to Koch’s postulates. The results of morphological examination, pathogenicity tests, and the ITS-5.8S rDNA, ACT, CHS-1, and G3PDH sequences confirmed Colletotrichum truncatum as the causal agent. This study provides news information about C. truncatum isolated from post-harvest papaya in Korea.