• The Plant Pathology Journal
• /
• v.17 no.6
• /
• pp.373.4-373
• /
• 2001

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.9 no.3
• /
• pp.174-178
• /
• 1989

The investigation was carried out to identify the main pathogen infected with sheath blight in corn plant during 1986-1987. The main fungi of sheath blight isolated from corn plant was identified as Rhizoctonia sobni. Sheath blight in corn plant was first found in early July and infected extremely from late July to end August. Severe sheath blight disease was observed in Gyeongido (Yeoju and Suweon) and Jeonnam (Kwangju) area. The rate of attack was associatied with management and cultural environments of corn plant. Dense planting increased sheath blight, but application of cattle compost reduced the rate of infection. A positive correlation was found between infection rate of shealth blight and concentration of soluble carbohydrate in corn plant (r=0.96). The varieties of Jinjuok, Suweon 83, Suweon 87, Suweon 89, P.3055, P.3160, DK689 and XCG 51 showed remarkable tolerance to sheath blight disease.

• Korean journal of applied entomology
• /
• v.1
• /
• pp.37-41
• /
• 1962

Fifty three varieties of potatoes were planted at Alpine Potato Research station at Takwalyong Kangwando Province since in 1962. The varieties planted were introduced front Japan, the United States and Germany. The varietal reaction was divided into five classes, and the results were following. Immune : Kennebec, Isola, Cherokee, Merrimack, Yoraku, Lisili. Cosima. Highly Resistant : Antze, Ragis Isola, Hessenkrone, Plymouth, Sebago, Pungo, Sieglinde, Anco, Essex. Resistant : Tawa, B-605-10, Sequoia, Grata, Concordia, Onaway, Holing 1. Nisego. Susceptible: Nordak, Pontiac, Benimaru, Early Gem, Chippewa, Chitose, Ohjiro, Red Bake, Norland, Katahdin. Highly Susceptible: Russet Burbunk, May Queen, Earlaine, Irish Cobbler, Feldeslohn, Red Warba, Chisago, Osseo, Paunee. Warba, Norgleam, Red Beauty, Red Burt, Danshaku, Namchak (Native variety), In general the verieties introduced from the United States and Germany were more resistant to late blight than those introduced from Japan. Especially the German varieties were immune or highly resistant to the disease except Feldeslohn. Early maturing varieties were more susceptible to late blight than the late maturing varieties in southern Korea.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.94.1-94
• /
• 2003

Control of bacterial blossom blight of kiwifruit (Actinidia deliciosa) has been mainly depended on chemical control. Recently cultural practices such as trunk girdling of kiwifruit trees and rainproof installation over kiwifruit trees also were conducted as the alternative control practices. Each of the control methods was evaluated for the best practicing conditions for the control of bacterial blossom blight of kiwifruit. Among the various combinations of spray times and spray periods, optimum spray program of antibiotics was turned out to be 3 times with intervals of 10 days from early May during the flowering season of kiwifruits. Optimum periods of trunk girdling of kiwifruit trees were from late March to late April. Trunk girdling with 20-30 mm wide showed best control efficacies on bacterial blossom blight, irrespective of the heights of girdling on trunks of kiwifruit trees. Optimum period of rainproof installation over kiwifruit trees was from March till late April, irrespective of installation methods.

• Korean Journal of Medicinal Crop Science
• /
• v.8 no.2
• /
• pp.151-156
• /
• 2000

Field experiments were conducted to investigate the yield and paeoniflorin content between healthy peony and blight plot of top part with every year during 3 years at June, July, August, September, separately. Stem length and diameter, No. of stem in the blight plot of peony were decreased in early in blight time compared with those in no blight growth. No. of flower buds per plant was 5.2, 4.6 in 3 year- grown and 4year-grown plots at late June blight compared with 11.5, 16.2 in no blight. No. of axillary flower was also similar to as above. Main root length and root diameter was most decreased in the plot of late June blight compared with healthy peony. No. of root more than 10mm of root diameter was small in order of blight time, namely Late June, July, August and September. The root dry yield of 4 year healthy peony was most high in 1,603kg per 10a, but it was lowed in 1,007kg in the plot lasted blight during 3years at late June. Paeoniflorin content was no different between 3year-grown and 4year-grown, but it was high in late June blight plot increased with the early in blight time.

• Korean Journal of Medicinal Crop Science
• /
• v.5 no.3
• /
• pp.206-210
• /
• 1997

The pathogenic fungi associated with blight of leaf and stem in peony were leaf spot (Alternaria sp.), powdery mildew (Erysiphe aquilegiae) and rust (Cronartium flaccidum). The infection of leaf spot and powdery mildew begins from late April to midMay and rust was infected in early June. Blight time of aerial part in peony started from late May and the ratio of blight on leaf and stem was more than 50% in late Aug. Yields of root by the incidence time of blight of leaf and stem were 69.1% in late June, 65.4% in late July and $87.6{\sim}92.7$% in August and September. The number of root of more than 10mm in root diameter blighted in late June and July was much lower than in August, but the paeoniflorin content in the former was much higher than the latter.

• Research in Plant Disease
• /
• v.30 no.3
• /
• pp.300-303
• /
• 2024

Since its initial outbreak in Korea in 2015, fire blight has consistently emerged annually. Fire blight outbreaks usually begin in May, peak in June, and decline in July in Korea. In this study, we analyzed cases that exhibit a distinct pattern of disease occurrence based on yearly weather conditions from 2020 to 2023. In 2020, fire bight disease occurrence began in late May. Although the disease incidence started late by the low temperatures in April, which caused flowering period delayed, the incidence increased significantly due to the high risk of blossom infection. In 2021, the first outbreak began in late April because the flower infection started in early April. In 2022, despite the high blossom infection risk during the flowering period in April and the high incidence of fire blight in May, the incidence decreased sharply from June due to the low rainfall in May. In 2023, due to torrential rains and hail in late June, the incidence of fire blight increased even in July. Considering the weather factors that affect the increase of fire blight disease, it is suggested that control measures to prevent the fire blight infection should be carried out before and after wind-driven rains.

• Korean Journal of Breeding Science
• /
• v.41 no.1
• /
• pp.61-67
• /
• 2009

"Early Valley", is an early maturing potato cultivar with high yield potential. "Early Valley" is a clonal selection resulting from the cross between 'Suncrisp' and 'A87109-10'. It has medium plant height and light green foliage. "Early Valley" has medium flowering habit and white flowers. Tubers are smooth, yellow skin, light yellow flesh, round tuber shape, medium eye depth, and medium dormancy and good keeping quality. It has stable yield under wide range of climatic conditions. "Early Valley" is resistance to late blight, but moderately susceptible to common scab and hollow heart. This cultivar is also resistant to potato rotting at harvesting during the raining season. "Early Valley" has high level of antioxidant activity (about three times higher) and vitamin C (higher by 40%) than the 'Superior'. This cultivar has high level of tuber uniformity and capable of yielding 36.56 t/ha which is 17.07% higher than the control potato cultivar 'Superior' under optimum agronomical practices.

• Plant Disease and Agriculture
• /
• v.5 no.1
• /
• pp.50-54
• /
• 1999

Leaf blight outbreak was investigated in sweet persimmon tree orchards in Korea during a three-year period from 1995 to 1997. The man percentage of sweet perismmon leaves blighted by Pestalotiopsis theae was 15.9%. The highest disease incidence was surveyed to 20% in Milryang. The disease began from early June to late October, and peaked in September and October. The lesion size on leaf ranged mainly 1-3 cm. The typical symptoms were large grayish concentric lesions of oval patterns of either mesophyll or margin of the leaf, and olde trees were more susceptible than younger ones.

• Asian Journal of Turfgrass Science
• /
• v.25 no.2
• /
• pp.160-170
• /
• 2011

Commercial formulation of fungicides was studied in vitro for sensitivity against Typhula species causal agents of Typhula blight. Efficacies of fungicides application, spray volume, nozzle types and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of Typhula blight of turfgrass during the winter season in Wisconsin. All fungicides effectively reduced the mycelial growth of eight isolates of Typhula spp. in vitro on potato dextrose agar (PDA) media. For inhibitory effects on mycelial growth of eight isolates, propiconazole was the most effective at $1.0{\mu}g$ active ingredient (a.i) / ml of PDA. Typhula incarnata two isolates were significantly more sensitive to all fungicides of PDA than six isolates of three varieties of T. ishikariensis. For 2 years in field experiment, unsprayed control has significantly more disease severity than seven fungicides were applied to field plots at two locations. Propiconazole was the most effective for controlling Typhula blight, at two locations in both years. The level of disease control was not dependent on fungicides spray volume or nozzle types at two locations. The disease damage treated with triadimefon applied time (early fall and late fall) was not significantly different at two location for two years.