• Research in Plant Disease
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• v.11 no.2
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• pp.185-192
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• 2005

In 1999 and 2002, 130 and 258 isolates of Colletotrichum spp. causing red pepper anthracnose were obtained from infected red pepper fruits, respectively. Their responses to 4 protective and 3 ergosterol biosynthesis-inhibiting(EBI) fungicides were investigated by observing their mycelial growth on PDA incorporated with different concentrations of each fungicide. The Colletotrichum isolates obtained in 1999 showed higher $EC_{50}$ values than those isolated in 2002 against three protective fungicides such as dithianon, chlorothalonil, and propineb, whereas the response was reversed toward other protective fungicide, iminoctadine. On the other hand, the isolates of year 1999 were more resistant against three EBI fungicides such as tebuconazole, hexaconazole, and prochloraz than those of year 2002; the $EC_{50}$ values of the former were 1.2-4.4 times higher than those of the latter, The responses of the Colletotrichum isolates toward protective and EBI fungicides were fluctuated according to regions, where the infected fruits were collected. On the other hand, the resis tance of Colletotrichum isolates to protective fungicides increased during monitoring from July to September, However, their responses towards EBI fungicides were not changed.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.355-362
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• 2016

This study was carried out to investigate the effects of rain-shelter types on growth, and fruit quality of red pepper (Capsicum annuum, 'Kemmaru') cultured in paddy. Applied rain-shelter types were outfield (control), simple rain-shelter plastic house with 2 rows (2R), simple rain-shelter plastic house with 4 rows (4R), and perfect plastic house (House). The plant height was the highest in Houses treatment. There was no difference in leaf length and width among the rain-shelter treatments. The fresh and dry weight of red pepper was high in order of House > 4R > 2R > Control. The ASTA value is irregular tendency among the treatments. Hunter's color value 'a' and 'b' was not different from among the treatments. Phytophthora blight, powdery mildew, bacterial spot were not occurred in all of treatments, and Anthracnose was only occurred in control. Mite, Microcephalothrips abdominalis, and Bemisia tabaci were not occurred in all of treatments, and aphid, Helicoverpa assulta, and virus were occurred all of treatments as same degree. Our results will provide rain-shelter cultivation of red pepper can be increase dry yield and decrease disease and insects.

• The Plant Pathology Journal
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• v.23 no.2
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• pp.37-44
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• 2007

Colletotrichum contains many important pathogens which cause economically significant diseases of crops like pepper, strawberry, tomato and apple. Forty four isolates were collected to characterize the diversity of Colletotrichum causing apple anthracnose in various regions of Korea. They were analyzed by random amplified polymorphic DNA (RAPD), internal transcribed spacer (ITS) of rDNA and partial $\beta$-tubulin gene DNA sequence, and culture characteristics on PDA and PDA-Benomyl. From the results of molecular analyses, 31 strains belonged to Colletotrichum gloeosporioides, ribosomal DNA group (RG) 4 of Moriwaki et al. (2002), 8 strains belonged to C. acutatum, A2 group of Talhinhas et al. (2005) and 5 strains to C. acutatum, A3 group of Talhinhas et al. (2005). Most isolates of C. gloeosporioides RG4 grew faster on PDA than strains of C. acutatum, A2 and A3 groups and most RG4 strains were sensitive to Benomyl. However, a few strains of RG4 grew slower and were resistant to Benomyl. On the basis of molecular characteristics, apple isolates of C. acutatum were clearly differentiated from red pepper isolates of the species, but apple isolates of C. gloeosporioides were not.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.479-490
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• 2018

Red pepper is seriously damaged by thrips (Thrips palmi) and anthracnose caused by Colletotrichum acutatum throughout its development. Because of biotic constraints, producers often depend on chemicals that are expensive and have adverse effects on the environment, operator, and beneficial insects. In addition, resistance is developed because of the repeated use of chemicals. In recent decades, the use of microorganisms in crop protection has become a credible alternative because it is eco-friendly. In this study, we aimed to select isolates with insecticidal and fungicidal activities against the pathogens that cause anthracnose and thrips. We treated T. palmi adults and juveniles with 13 strains of entomopathogenic fungi (isolated from the soil by using the insect-bait method), and 6 strains showed excellent insecticidal activity (70-100%) 5 days after the treatment. The selected isolates were cultured with C. acutatum to screen for the strain with excellent anti-fungal activities, among which an isolate FT333 showed more than 95% control efficacy against C. acutatum in vitro. The isolate was identified as Isaria javanica through its morphological characteristics and phylogenetic analysis of the ITS and ${\beta}-tubulin$ nucleotide sequences. The Isaria javanica FT333 isolate could be used effectively for dual bio-control of thrips and anthracnose during red pepper cultivation.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.234-241
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• 2008

Agrobacterum tumefaciens-mediated transformation (ATMT) is becoming an effective system as an insertional mutagenesis tool in filamentous fungi. We developed and optimized ATMT for two Colletotrichum species, C. falcatum and C. acutatum, which are the causal agents of sugarcane red rot and pepper anthracnose, respectively. A. tumefaciens strain SK1044, carrying a hygromycin phosphotransferase gene (hph) and a green fluorescent protein (GFP) gene, was used to transform the conidia of these two Colletotrichum species. Transformation efficiency was correlated with co-cultivation time and bacterial cell concentration and was higher in C. falcatum than in C. acutatum. Southern blot analysis indicated that about 65% of the transformants had a single copy of the T-DNA in both C. falcatum and C. acutatum and that T-DNA integrated randomly in both fungal genomes. T-DNA insertions were identified in transformants through thermal asymmetrical interlaced PCR (TAIL-PCR) followed by sequencing. Our results suggested that ATMT can be used as a molecular tool to identify and characterize pathogenicity-related genes in these two economically important Colletotrichum species.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.317-321
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• 2008

In a search for plant extracts with in vivo antifungal activity for plant diseases, we found that the methanol extract of Myristica malabarica fruit rinds effectively suppressed the development of several plant diseases. The methanol extract exhibited potent 1-day protective activity against rice blast, tomato late blight, wheat leaf rust and red pepper anthracnose. It also showed 7-day and 4-day protective activities against the plant diseases. Three antifungal resorcinols were isolated from the methanol extract of M. malabarica fruit rinds and identified as malabaricones A(MA), B(MB), and C(MC). Inhibitory activity of the three resorcinols against mycelial growth of plant pathogenic fungi varied according to compound and target species. All three compounds effectively reduced the development of rice blast, wheat leaf rust and red pepper anthracnose. In addition, MC was highly active for reducing the development of tomato late blight. This is the first report on the antifungal activities of malabaricones against filamentous fungi.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.185-191
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• 2012

For initiation of resistance breeding program of the red pepper, 21 PR ($Phytophthora$ resistance) cultivars, 36 cultivars collected from USA and 'Supermanitta' which is a susceptible cultivar against phytophthora blight were assayed against phytophthora blight, powdery mildew, and anthracnose. For seedling assay of phytophthora blight, three different mating type strains of $Phytophthora$ $capsici$ were used (A1, A2, Sterile). The result showed that most of the pepper of PR cultivars were resistance or moderately resistance at each mating type. 'Yeokganghongjanggun' was resistant to all three $P.$ $capsici$ strains and 'PR-Datta' and 'PR-Manitta' were resistant or moderately resistant at each type. In case of the collected cultivars, 'NuMex J.E.Parker', 'Omni Color', and 'SCM334' were resistant to all the three types and some cultivars including 'Sweet Banana' and 'Tabasco' were moderately resistant to each type fungi. 'Orange Habanero' and 'Black Cuban' were resistant to powdery mildew and 'Supermanitta' and 'PR Keumdong' were moderately resistant, while 'Santa Fe Grande', 'NuMex Pinata' and 'Puya' were very susceptible. In the case of anthracnose, 'Aji Limon' and 'Capsicum baccatum var. pendulum 3-4' were resistant and 'Pobalno', 'Omni Color', 'Negro', 'Mesilla', 'Mulato', 'Bhut Jolokia', 'Big Dipper', 'Black Cuban', 'NuMex Pinata', and 'NuMex Big Jim' were moderately resistant. The most PR cultivars except 'Taesan' were susceptible or very susceptible. These resistant individuals identified through this experiment can be used as sources of resistance to pepper pathogens in the future breeding programs.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.107-113
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• 1986

Each of 48 monoconidial isolates of Colletotrichum gloeosporioides Penz. obtained from diseased fruits of pepper was classified into strain G or strain R based upon pathogenicity to green and red fruits, morphology of conidia, and cultural characteristics in potato dextrose agar. The strain G was designated for isolates to cause anthracnose symptoms both on green and red fruits. All isolates of the strain G produced conidia abundantly. but produced no perithecia and setae in PDA. Conidia of all isolates in the strain G were attenuated or round at one end. The optimum temperature for mycelial growth of strain G was $26-28^{\circ}C$. The mycelia of strain G in PDA appeared to be whitish when young, and turned to be dark in old culture. Symptoms on pepper fruits caused by the strain G were somewhat sunken to be circular to elliptical lesions. Yellowish conidial masse were observed at the center of lesions, and the lesions turned to irregular shape and to reddish brown color in the later stage of disease development. No setae were visible on the acervuli. The strain R was designated for isolates to cause anthracnose symptoms only on red fruits of pepper. All isolates of the strain R produce conidia, and perithecia of Glomerella cingulata (Stonem.) Spauld. & v. Sch. in PDA. Some isolates of the strain R produced setae in culture under fluorescent light. Conidia of all isolates in the strain R were round and blunt at the ends. The optimum temperature for mycelial growth of strain R was the same as that of strain G. The mycelial growth of strain R was faster than that of strain G in PDA. The mycelia of strain R in PDA appeared to be gray to dark. Symptoms on pepper fruits caused by the strain R were circular to irregular black ring-spots Short setae or no setae were visible on the acervuli.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.41-46
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• 1986

Exogenous factor and nutrients affecting for conidial germination of Colletetrichum dematium f. sp. capsicum causing red pepper anthracnose were studied by slide germination test. Optimum temperature of conidial germination was at $28^{\circ}C$, ranging 15 to $35^{\circ}C$. Optimum pH was at 5.5, ranging 4.5 to 8.0, and more than 90% of relative humidity (RH) was optimum. Poor conidial germination of the fungus was observed on sterile distilled water, but potato sucrose broth (PSB), red pepper fruit broth (RPFB), green pepper fruit broth (GPFB) and pepper leaf broth (PLB) furnished a satisfactory nutrients for conidial germination. Exogenous supply of carbon and nitrogen sources were essential for conidial germination, while potassium, phosphorous and sulfur were not evident as that for carbon and nitrogen. Soluble starch was the most suitable as a carbon source for conidial germination and followed by D-glucose, D-galactose and lactose in that order. Maximum germination was attained in the $1{\times}10^4$ conidia per ml. Germination was decreased with increment of conidial concentration, and in the density of $5{\times}10^4$ conida per ml, germination was nearly supipressed. It suggested existing a self-inhibitor. Non-washed conidia germinated more than washed conidia, and conidial germination was also gradually decreased by increasing conidial density.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.7-11
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• 1986

Nine Korean local cultivars and 34 PI lines of pepper were tested for resistance to anthracnose (Colletotrichum dematium). Red ripe fruits were harvested, punctured and inoculated by spraying and dropping a conidial suspension of Colletotrichum dematium. Resistance was evaluated by measuring the diameter of ripe rot lesions developed on and around the puncture. The results obtained are as follows : 1. PI 201232, PI 224451, PI 257044, PI 257119, PI 257099, PI 224433, PI 244668, PI 257102, PI 173877, Namji, Cheongryong, and Seodong were the least diseased and considered to be resistant. 2. PI 241670, PI 244670, and PI 224423 were the most diseased and considered to be susceptible. 3. Others were in between the two extremes and considered to be intermediate.