• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.72-73
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• 1980

The spermagonial state of Cronartium ribicola J. C. Fisher appeared on the discolored bark of Korean pine (Pinus koraiensis Sieb. & Zucc.) from late August through middle of October in Korea. A large number of ellipsoid or ovoid spermatia were contained in the spermagonial exudates that appeared on the bark of infected trees. In the spring (April-May) following the appearance of spermagonia, aecia broke through that part of the bark which had been occupied by spermagonia the year before.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.97-100
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• 1975

Korean white pine (Pinus koraiensis Sieb. & Zucc.), native to Korea and currently the most important timber species in Korea is being threatened by a blister rust discase caused by a Cronartium species. The fungus has been tentatively identified as Cronartium ribicola Fischer. The fungus alternates between P. koraiensis and Pedicularis resupinata L. (a herbaceous perennial) under natural conditions in Korea although experimentally it has been shown to infect several Ribes species. The taxonomic diagnosis of the causal fungus is not fully resolved. A review of the status of this rust disease on P. koraiensis and other possible hosts in Korea and its potential international significance along with present work underway in Korea is discussed.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.61-63
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• 1978

Both bark and wood sections obtained, by cutting with a razor blade, from living tissue of Cronartium ribicola cankers of Korean white pine (Pinus koraiensis) were transferred to a mixture of 2 parts of chloroform and 1 part of methanol, and the sections were stained using a modified lactophenol cotton blue. The formula for this staining is as follows: Lactic acid 20gm, phenol crystal 20gm, cotton blue 0.05gm, and 60% EtOH 100ml. The rust hyphae and haustoria were stained blue, and the wide hyphae with straight or curved haustoria could be distingwished from the pine tissue.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.76-81
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• 1983

Pedicularis spp. are the alternate hosts of the white pine blister rust fungi in the forests of Korea, and Ribes spp. were found as other alternate hosts by artificial inoculation test. New biotypes (races) with different host selectivity and pathogenicity of the causal fungi were speculated at various places in Korea. The aeciospores of the fungi were collected from two isolated places, Pyeongchang and Namwoen, and artificially inoculated on Pedicularis resupinata and six species of the genus Ribes. Among the tested alternate host species, P. resupinata and R. montigenum were only susceptible to both the Pyeongchang population and the Namwoen population, showing similar pathogencity between the two fungai populations. Three white pine species were planted in fungus-infested stands to study the susceptibility of each tree species. Four years later, 17.7% of Pinus koraiensis and 26.3% of the P. strobus were infected, but P. parviflora was free from attack. From the above results, it was concluded that the white pine blister rust fungus populations in Korea are of the same biotype, with P. koraiensis and P. strobus as aecial hosts, and Pedicularis spp. and Ribes spp. as telial hosts.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.112.2-112
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• 2003

Levels of blister rust infection (from Cronartium ribicola) varied in western white pine(Pinus monticola Dougl.) seedlings grown in two nurseries in northern Idaho. This observation suggested the potential importance of environmental components operating on the blister rust pathosystem. In an experiment designed to test the influence of environmental conditions at two nurseries, seedlings of a single genetic source were unintentionally held in cold storage for 6 months longer at one nursery than at the other. Subsequently, these seedlings, which had been growing under nursery conditions for 7 months or 1 month, were inoculated with blister rust spores on September 9th, 1999. Infection efficiency measured on the seedlings with only 1 month of growth was 70X greater than on the seedlings that had 7 months for their new growth to mature. Results from this nursery test and infection levels of northern Idaho resistant selections in mild climates suggest that expression of genes related to rust resistance in western white pine can be manipulated by regulation of phonology. If so, several new molecular tools may be employed to enhance our understanding of environmental regulation of genes for blister rust resistance.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.277-284
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• 1987

Infection rate of the blister rust was investigated with special reference to the effect of eight stand factors at 221 plots selected from 131 Korean pine(Pinus koraiensis S. et Z,) stands, and the data were analyzed by multivariated statistical analysis. Environmental factors such as the density of Pedicularis spp., alternate hosts of the Korean pine blister rust, altitude, stand age, aspect, and pruning treatment, from the highest to the lowest were found to be related to the occurrence of the rust disease, Density of Pedicularis spp, was the most closely related to the' infection rate than any other factors, Especially, Pedicularis spp. growing naturally inside the pine stand had an important effect on the infection rate, but those on the outside more than 100m away had little effects, The higher the elevation, the heavier the infection rate. Infection was the heaviest at the altitudes of above 1,000m with high relative humidity and cool temperature. Infection rate was severe in young stands below 10 years old and had a reducing tendency as they mature. Stands above 16 years old were more resistant. The infection rate by the aspect of stand was higher at E- NE and W -SW exposures than at S-SE and N -NW. The infection rate at non-pruning stands was higher than at pruning stands with the lowest branch being at least 60cm high from the ground.