• Korean Journal of Environmental Agriculture
• /
• v.25 no.3
• /
• pp.276-283
• /
• 2006

To evaluate the effectiveness of the foliar spray of calcium on "Baekdo" peach fruit, we carried out experiments in the orchards. The sprays were applied with $CaCl_2\;(Ca:\;400mg.kg^{-1})\;and\;CaCl_2$ with adjuvants (amino acid, $2g.kg^{-1}$; phytic acid, $2ml.kg^{-1}$ and wood vinegar, $2ml.kg^{-1}$) for four times from June 12 through July 4 at weekly intervals. The fruits and leaves were evaluated for Ca content, firmness and incidence of Brown rot caused by Monilinia fructicola at harvest To evaluate fruit quality included Ca content, firmness natural decay during the storage, the fruits were stored at room temperature for 14 days. The Ca content in leaf and fruit flesh at harvest was significantly increased (P=0.05) in $CaCl_2$ + amino acid treatment among $CaCl_2$ treatments. However, there was not significant Ca content in fruit peel. The firmness of flesh increased significantly (P=0.05) in $CaCl_2$ + amino acid treatment. The natural decay (Rhizopus stolonifers) during storage at the room temperature for 14 days, the fruit treated with $CaCl_2$ + wood vinegar exhibited lowest (P=0.05) incidence. Also, the firmness of the fruit during storage was firmer with treated $CaCl_2$ than untreated fruit. In the treatments of $CaCl_2$ + phytic acid and $CaCl_2$ + amino acid, it was possible to reduce incidence of Brown rot caused by M. fructicola most effectively in the field. In addition, inoculation with M. fructicola in fruits was also the most effective treatment for inhibiting disease development in vitro. These results suggested that the foliar spray of $CaCl_2$ with adjuvants increased the content of Ca and firmness of the fruits positively. It also inhibited the natural decay and the Brown rot effectively.

• The Plant Pathology Journal
• /
• v.17 no.6
• /
• pp.367.5-368
• /
• 2001

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 1999.04a
• /
• pp.25.1-25
• /
• 1999

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2000.10a
• /
• pp.12.2-12
• /
• 2000

• Research in Plant Disease
• /
• v.8 no.4
• /
• pp.245-249
• /
• 2002

Monosporascus cannonballus, a soilborne ascomycetes is recently described in Korea that causes root rot/vine decline of cucurbits. The effect of Monosporascus root rot disease on photosynthetic activity and growth was studied on oriental melon plants. At harvest stage, photosynthetic activity of diseased oriental melon plants was lower and stomatal resistance was higher than healthy plants, while xylem exudates were not observed in diseased plants. There was no difference in mineral contents of the leaves and stems between diseased and healthy plants. Leaf area, fresh and dry weights, and fruit weights of the plants were markedly decreased in diseased plants compared to those of healthy plants.

• Korean Journal Plant Pathology
• /
• v.14 no.6
• /
• pp.642-645
• /
• 1998

A severe pink mold rot on matured melon fruits occurred under a glass tunnel cultivation in Chinju at Kyeongasngnam-do Agricultural Research and Extention Services on May of 1998. Basal portion of the fruits toward blossom end was preferably infected and colonized by the fungus. The causal fungus consistently isolated from the lesions was identified as Trichothecium roseum based on following mycological characteristics. Conidia were hyaline or brightly colored, 2-celled, ovoid or elipsoid, characteristically held together zi-zag chains. Conidiophore was long, slender, simple, septate, bearing conidia-meristem arthrospores-apically, singly when young and successively by slight growth of conidiphore apex. Optimum temperature for mycelial growth and conidial germination was recorded at 20~$25^{\circ}C$. However, over 48% of the fungal conidia were germinated at 15$^{\circ}C$ and mycelial growth was only slightly slower than $25^{\circ}C$. The temperature profiles and high humidity available during the cultivation were considered favorable for the pathogen as showing 22% infection rate on matured melon fruits cv. Saros. This is the first report of pink mold rot of melon caused by T. roseum in Korea.

• The Plant Pathology Journal
• /
• v.36 no.6
• /
• pp.570-578
• /
• 2020

Rhizopus rot is a serious postharvest disease of various crops caused by Rhizopus spp. and controlled mainly by synthetic fungicides. We detected the antifungal activity of a culture extract of Setosphaeria rostrata F3736 against Rhizopus oryzae. The active ingredient was identified as moriniafungin, a known sordarin derivative, which showed minimum inhibitory concentrations of 1-8 ㎍/ml against Colletotrichum spp. and 0.03-0.13 ㎍/ml against Rhizopus spp. in vitro. Moriniafungin showed protective control efficacies against Rhizopus rot on apple and peach fruits. Treatment with 25 ㎍/ml moriniafungin delimited the lesion diameter significantly by 100% on R. oryzae-inoculated apple fruits compared with the non-treated control. Treatment with 0.04 ㎍/ml of moriniafungin reduced the lesion diameter significantly by 56.45%, and treatment with higher concentrations of 0.2-25 ㎍/ml reduced the lesion diameter by 70-90% on Rhizopus stolonifer var. stolonifer-inoculated peach fruit. These results suggest moriniafungin has potential as a control agent of postharvest diseases caused by Rhizopus spp.

• The Plant Pathology Journal
• /
• v.38 no.5
• /
• pp.513-521
• /
• 2022

Our study was carried out to determine the control efficacy of sodium hypochlorite (NaOCl) for violet root rot caused by Helicobasidium mompa in apple. The experiment was conducted in the farm located at Chungbuk province in South Korea from 2014 to 2016. When infected apple trees were treated at least two or three times with 31.25 and 62.5 ml/l available chlorine content in NaOCl, it greatly increased the rooting of rootstock, and restored the tree crown density by 44.4-60.5%. In addition, the number of commercial fruit setting was increased by 54.3-64.5%, and the total starch content in shoots was significantly higher than other non-treated apple trees. However, the untreated disease control and thiophanate-methyl WP treated trees showed the symptom of dieback. Therefore, our results indicate that the drenching treatment of NaOCl with 31.25-62.5 ml/l available chlorine content more than two times from late fall to early spring could effectively control the violet root rot and recover tree vigor up to 60%.

• Korean Journal of Agricultural Science
• /
• v.40 no.3
• /
• pp.191-196
• /
• 2013

This study was conducted to investigate the effect of temperature during transportation and continuing shelf-life on fruit quality and the occurrence of physiological disorder to set up the appropriate exportation temperature condition in Asian pear (Pyrus pyrifolia Nakai) 'Hanareum'. In the experiment of simulated exportation headed for USA, the fruits transported at $1^{\circ}C$ showed less weight loss than those of $5^{\circ}C$. Market temperature appeared as a key factor for keeping freshness of exported pear fruits rather than transportation temperature. Quality factors such as high flesh firmness and low incidence of fruit rot and physiological disorders including core breakdown and pithiness were attained at the fruits maintained at $18^{\circ}C$. Approximately two times higher incidence of physiological disorders and of fruit decay rates were observed in the fruits distributed at $25^{\circ}C$ than the those of $18^{\circ}C$. Therefore, temperature management during marketing resulted as an important factor for maintaining fruits quality in the process of pear fruit exportation.

• Mycobiology
• /
• v.28 no.3
• /
• pp.158-162
• /
• 2000

Twenty-three isolates of Fusarium spp. were obtained from decayed citrus fruits in the fields and storages in 1998-1999. Of them, six and five isolates belonged to F. proliferatum and F. moniliforme, respectively, which were the most common. F. solani and F. sambucinum had each two isolates, F. equiseti had one isolate and seven isolates were unidentified. They produced symptoms of two types in pathogenicity test: those with leathery, beige to light or dark brown, and sunken lesions without surface mycelium (type-1) and those with lesions covered with white, beige or pink surface mycelium (type-2). Four of six isolates identified to F. proliferatum and two unidentified isolates produced type-1 lesions, and all isolates identified to F. moniliforme, F. solani, F. sambucinum, F. equiseti and five unidentified isolates produced type-2 lesions.