• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.81-89
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• 2004

The effects of developed grape bags on the micro-climate changes of bag, physiological disorder, pathogenic decay, quality and harvest time evaluation in 'Campbell Early' grapevines were studied. The temperature and light transmittance of developed grape bags showed no differences compared with the onces of conventional bag and non-bagging, but relative humidity and the amount of water evaporation were changed in all treatments. The occurrence of unfertilized fruit, poorly colored fruit, russet and gray mold rot showed no significant difference in all treatment at harvest time. Developed grape bags decreased effectively the occurrence of cracking fruit and bitter rot in 'Campbell Early' fruit. There was no difference in growth of cluster and berry, soluble solids and total acidity in fruits, degree of skin color and bloom appearance at harvest time. The skin color and fruit boom and harvest time evaluation in developed grape bags were resulted excellent compared with the once of conventional bag and non bagging.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.402-407
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• 1998

Phytophthora rot on jujube fruit has occurred at several cultivation areas in Kyung-buk and Kyung-nam provinces. Symptoms consisted of brownish to reddish rot on fruits resulting in early drop or mummification. The causal fungus isolated from infected fruits and adjacent leaf stalks was identified as Phytophthora citricola, which has never been reported in Korea. Sporangia were semi-papillate, noncaducous and highly variable in shapes. Plerotic oospores with paragynous antheridia were abundant is single cultures. Sporangia of two isolates were measured as 38-76$\times$20-40 ${\mu}{\textrm}{m}$ and averaged 51.4$\times$27.0 and 55.6$\times$36.0 ${\mu}{\textrm}{m}$. Oogonia were ranged from 26 to 36 ${\mu}{\textrm}{m}$ and averaged 31.3 and 32.0 ${\mu}{\textrm}{m}$. Colony pattern was slightly radiated with sparse aerial mycelia on common media. Minium, optimum and maximum temperatures for mycelial growth were recorded at 7, 25, and 32$^{\circ}C$, respectively. Among tested media, 10% V8A was the best and $25^{\circ}C$ was better than 15$^{\circ}C$ for oospore formation of the fungus. The jujube isolates of P. citricola were readily differentiated from other closely related species in the genus, namely; P. nicotianae, P. citrophthora, P. cactorum, P. capsici, and P. plalmivora on the basis of PCR-RFLP of r-DNA. The fungus showed strong pathogenicty to jujube, apple, pear, orange, persimmon and eggplant, and relatively weak to citron, tomato, pepper and cucumber. In this study, P. citrocola is firstly identified and jujube fruit rot caused by the fungus is recorded as a new disease in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.83-85
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• 2012

The causes of blossom-end rot (BER) are still not understood clearly, although there was a lot of research on the development of BER over 100 years. This experiment was conducted to investigate the influence of Ca content of fruit on the incidence of BER in red pepper. BER affected fruits and healthy fruits had been harvested and the samples were divided into two parts, the upper and the lower, for chemical analysis to determine the content of mineral nutrients in the tissue. The content of nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) was higher in the BER affected fruits and the difference of each nutrient content was revealed much larger in the lower part of the fruit but there were no significant differences in calcium content between the BER and the healthy fruits of red pepper, in this experiment. The results indicate that it is difficult to find a certain relation between the calcium content of the fruit and the occurrence of blossom-end rot.

• The Plant Pathology Journal
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• v.17 no.2
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• pp.110-113
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• 2001

Post-harvest diseases of kiwifruit caused severe damages on the fruits during storage, transportation, marketing and consumption. Phomopsis sp. was reported to be one of the major causal organisms of post-harvest fruit rots of kiwifruit. Symptoms of stem-end rot caused by Phomopsis sp. appeared at the stem-end area of the fruit as it ripened. The brown pubescent skin at the area became soft and lighter in color than the adjacent firm healthy tissues. A watery exudate and white mycelial mats were frequently visible at the stem-end area forming a water-drop stain down the sides on the dry brown healthy skin. When the skin was peeled back, the affected flesh tissue was usually watersoaked, disorganized, soft and lighter green than the healthy tissue. Phomopsis sp. was consistently isolated from the diseased fruits, and its pathogenicity was confirmed by an artificial inoculation test on healthy fruit of kiwifruits. The mycological characteristics of the telemorph state of the fungus produced on potato-dextrose agar were in accordance with those of Diaporthe actinidiae. This is the first report on the occurrence of a telemorph state of D. actinidiae as the causal organism of stem-end rot of kiwifruit in Korea.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.205-217
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• 2024

Brown rot disease, caused by Monilinia spp., poses a significant threat to pome and stone fruit crops globally, resulting in substantial economic losses during pre- and post-harvest stages. Monilinia fructigena, M. laxa, and M. fructicola are identified as the key agents responsible for brown rot disease. In this study, we employed the amplified fragment length polymorphism (AFLP) method to assess the genetic diversity of 86 strains of Monilinia spp. isolated from major stone fruit cultivation regions in South Korea. Specifically, strains were collected from Chungcheong, Gangwon, Gyeonggi, Gyeongsang, and Jeolla provinces (-do). A comparative analysis of strain characteristics, such as isolation locations, host plants, and responses to chemical fungicides, was conducted. AFLP phylogenetic classification using 20 primer pairs revealed the presence of three distinct groups, with strains from Jeolla province consistently forming a separate group at a high frequency. Furthermore, M. fructicola was divided into three groups by the AFLP pattern. Principal coordinate analysis and PERMANOVA were applied to compare strain information, such as origin, host, and fungicide sensitivity, revealing significant partition patterns for AFLP according to geographic origin and host plants. This study represents the utilization of AFLP methodology to investigate the genetic variability among M. fructicola isolates, highlighting the importance of continuous monitoring and management of variations in the brown rot pathogen.

• Mycobiology
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• v.40 no.3
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• pp.214-216
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• 2012

Soft rot on banana fruit caused by Rhizopus oryzae was identified for the first time in Korea. Colonies were white to light brown and formed numerous sporangiospores. Optimum temperature for mycelial growth was $30^{\circ}C$. Sporangia were globose and $30{\sim}200{\mu}m$. Sporangiophores were usually straight, $8{\sim}20{\mu}m$, and rhizoids usually in groups of 3~5. Columella were globose to sub-globose and $90{\sim}110{\mu}m$. Sporangiospores were sub-globose or oval and $4{\sim}10{\mu}m$. Based on its mycological characteristics, molecular analysis, and pathogenicity to host plants, this fungus was identified as Rhizopus oryzae Went & Prisen Geerligs. This is the first report of soft rot on banana caused by Rhizopus oryzae in Korea.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.252-257
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• 2007

This study was carried out to clarify the effects of antifungal Streptomyces sp. isolated from the soil grown kiwifruit on the growth inhibition of fruit rot (Botryosphaeria dothidea) infected in kiwi fruit plants in the southwestern districts of Jeonnam. Two hundred and fifty microorganisms were isolated and examined into the antifungal activity against Botryosphaeria dothidea. We screened and isolated six bacterial strains which have a strong inhibition against Botryosphaeria dothidea. And the best antifungal strain designated as the strain #120 showing 96.0% antifungal activity against Botryosphaeria dothidea was finally selected. The strain #120 was identified as Streptomyces sp. #120 based on its morphological, physiological, biochemical and chemotaxonomic characteristics.

• Research in Plant Disease
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• v.8 no.4
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• pp.215-219
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• 2002

Fruit rot of pomegranate (Punica granatum) caused by Coniella granati were observed in several farmer's fields in Gwangdo-myon, Tongyeong City, Gyeongnam Province, Korea. The symptoms occurred on fruit with rotting then eventually dropping and mummification. The colony color of causal fungus was whitish on potato dextrose agar. Conidia were single celled, pale brown or olive in color at maturity, straight or slightly curved fusiform in shape, and were 10.3~17.4$\times$2.8~4.0 ${\mu}{\textrm}{m}$ in size. Conidiogenous cell were hyaline, branched only at the base aseptate, elongate, phialidic, enteroblastic and 12.4~1.4$\times$2.8~3.6 ${\mu}{\textrm}{m}$ in size. Pycnidia were black in color and globose in shape and 124.6~228.4 ${\mu}{\textrm}{m}$ in size. Optimum temperature for mycelial growth was $25^{\circ}C$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Coniella granati. This is the first report on the fruit rot of pomegranate caused by Coniella granati in Korea.

• Research in Plant Disease
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• v.13 no.1
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• pp.53-56
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• 2007

The fruit rot of pumpkin caused by Sclerotium rolfsii occurred sporadically at Gyeongsangnam-do Agricultural Research and Extension Services, Korea in 2004 and 2005. The typical symptom of the disease included water-soaking, fruit rotting and wilting. White mycelial mats were spread over infected fruits and then sclerotia were formed on the lesions and near soil surface. The sclerotia were globoid in shape, 1$\sim$3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation was at $30^{\circ}C$ on PDA and the hyphal width ranged from 4 to 8 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the fruit rot of Cucurbita spp. caused by S. rolfsii in Korea.

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.63-70
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• 1986

Severity of incidence of white rot on apple fruit ranged from 5 to 16% and averaged 9% over major apple growing area in 1981. An isolate of Botryosphaeria ribis obtained from rotted apples developed lesions on leaves, branches and fruits of apple, pear, peach and grape in a series of wound inoculation test. B. ribis grew well on both potato sucrose agar and oatmeal agar. The best condition for vegetative growth on these two media was at $25{\sim}30^{\circ}C$ pH 4 and $10{\sim}15%$ sucrose content under light illumination. Rot development on fruit was first observed in the orchard at early August when sugar content in fruit reached 9.0%. Thereafter, number of rotted apples increased as sugar content increased. There was no correlation between the pH of juice of fruit and rot incidence. Infection on fruit began to occur as early as mid-June when young fruits were formed and infections were continued until harvest. When apple fruits were collected at 10-day intervals from the orchard beginning from early June and were wound-inoculated with B. ribis, rot lesion developed regardless of the stage of fruit growth. Incidence of white rot in the orchard was severe on Golden-delicious and Yukou, intermediate on Aoli, Fugi and Indo, and least on Jonathan and Red-delicious.