• Agrochemical news magazine
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• v.25 no.6 s.199
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• pp.41-43
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• 2004

• Plant Disease and Agriculture
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• v.4 no.2
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• pp.15-16
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• 1998

• Agrochemical news magazine
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• v.21 no.5 s.158
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• pp.42-43
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• 2000

• Current Research on Agriculture and Life Sciences
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• v.18
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• pp.19-25
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• 2000

$F_2$ populations of the crosses KC47-1 (PI244670) ${\times}$ KCB14-2-2-3-2 (PI201234), KC220-1 ${\times}$ KC268 and $F_3$ bulk populations of the crosses KC47-1${\times}$KC263 (AC2258), KC47-1${\times}$KCB13-2-1 (PI201232), KC47-1${\times}$KCB13-4-2 (PI201232), either one parent of which was resistant to Phytophthora blight, were tested for both gray leaf spot and Phytophthora blight by serial inoculation with Stemphylium solani or a mixture of S. solani and S. lycopersici, and P. capsici in 1999. In 2000, $F_3$ and $F_4$ lines or populations developed from the respective $F_2$ or $F_3$ selections in the previous year were evaluated for resistance to both diseases. A significant progress in resistance to both diseases was achieved by selection.

• The Korean Journal of Mycology
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• v.19 no.3
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• pp.231-237
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• 1991

This study was conducted in order to find out biological control of sesame wilt and blight caused by Fusarium of oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica by using Streptomyces spp. Two sesame pathogens, Fusarium oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica were purely isolated from diseased sesame plants of the field. Streptomyces species were isolated from 72 soil samples collected from red pepper and sesame uplands in Chungbuk and selected as antagonists according to the results of dual culture. The selected Streptomyces isolates such as St-11 and St-20 were confirmed their antagonistic effect through mycelial inhibition zone and inhibitory effects on the mycelial growth of the pathogens by culture filterate of the antagonists. Inhibitory effects on the conidial germination of Fusarium oxysporum vasinfectum and Phytophthora nicotianae parasitica by the antagonists were also tested in addition to mycelial Iysis. The antagonists St-11 and St-20 showed inhibitory effect on growth of sesame seedlings after seeds soaked in the suspension. Effect of soil inoculation with antagonist St-11 showed 40 to 78 percent of control effect for two diseases in comparison with control under greenhouse.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.127-133
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• 1991

PI201232, a pepper line resistant to Phytophthora capsici Leonian, was crossed with PI2713222 and P1163192, resistant to Xanthomonas campestTis pv. vesicatoria (Doidge) Dye and inheritance of the resistance to each disease and genetic relationship between the two disease resistances was studied. Non-hypersensitive resistance to race 3 of X. c. pv. vesicatoria of PI271322 was inherited in a quantitative mode. Resitance to P. capsici of PI201232 was inherited in a mode close to two dominant alleles. Hypersensitive resistance to race 1 of X. c. pv. vesicatoria of PI271322 was inherited in a mode of single dominant allele. PI 163192 was consistently resistant to both race 1 and race 3 of X c. pv. vesicatoria and the resistance was inherited in a quantitative mode with high dominance effect. Resistance to X. c. pv. vesicatoria was inherited independently from resistance to P. capsici.

• Research in Plant Disease
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• v.12 no.1
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• pp.46-50
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• 2006

The microorganisms with the antifungal activity against Phytophthora capsici and Colletotrichum acutatum and the plant growth-promoting activity were screened from a forest and natural fields of Gajang-Dong, Sangju-city. One of the isolates, Streptomyces griseofuscus 200401, was selected as a good plant growth-promoting strain in this study. In greenhouse test, the number of leaf, fresh weight, and dry weight of pepper plants, that were grown with treatment of culture suspension or powder containing S. griseofuscus 200401, were higher than those without the bacterial cells. Cultivation of S. griseofuscus 200401 strain for 7 days in a nutrient rich medium produced ammonium chloride up to 0.13 ${\mu}g/ml$ in the culture solution of S. griseofuscus. Treatment of the selected strain significantly reduced the severity of the late blight of pepper plants to show the equivalent disease control activity to chemical fungicide. This study suggests that S. griseofuscus 200401 strain could be a potential biological agent with the biocontrol activity and the plant growth-promoting activity.

• Research in Plant Disease
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• v.16 no.2
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• pp.158-162
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• 2010

Four promising biocontrol agents against Phytophthora capsici were selected from 507 bacterial isolates collected from rhizosphere soils and roots of pepper plants. In vitro experiment, these four biocontrol agents inhibited mycelial growth, germination of cystospores, and formation of zoosporangia and zoospores of Phytophthora capsici. In the pot experiment, the four biocontrol agents showed control efficiency higher than 70%. In greenhouse experiment, the isolates G28-6 gave the control value of 79.4%. These four biocontrol agents successfully colonized in the population density beyond 105 cfu/g on roots of pepper in vitro. The isolates G28-6 was identified as Pseudomonas aurantiaca, based on its cultural, morphological, and biochemical characterization and 16S rRNA gene sequence analysis.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.177-182
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• 1999

A fungal infection assay between normal and transgenic potato harboring chitinase gene in cultivar Belchip was investigated. In the first stage of experiment, seven transgenic lines having 12cm tall were tested for their resistance against potato late blight pathogen Phytophthora infestans by infection with the zoospores, artificially, Susceptibility to potato late blight infection could be classified into three types based on the rate. In terms of resistance to the disease, two lines were higher, two lines were more suppressive, and three lines were similar as compared with the control. In the following experiment, only 2 risistant lines and 1 suppressed line were used to confirm the resistance again. The results of both experiments were similar. Furthermore, two highly resistant transgenic lines grown in field exhibited a higher resistance than control under the conditions of natural ocurrence of the fungal disease.

• Research in Plant Disease
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• v.18 no.1
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• pp.35-39
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• 2012

Occurrence of tomato late blight (Phytophthora infestans) has caused significant losses in tomato yield in all over the world. Evaluation of the level of resistance in tomato gene resources for main breeding and initiation of the resistance breeding program are important for control of this disease. Resistant assay of 78 tomato cultivars/lines to late blight in pots and field experiment was carried out under controlled and natural conditions in 2009. All commercial cultivars including 'Legend' were susceptible. However, 10 lines including KNU-2, KNU-6-1, KNU-11, KNU-13, KNU-14-1 lines distributed from University of California, Riverside and L3708, $AV107-4{\times}L3708$, $07-15{\times}L3708$, $BS67{\times}L3708$ lines which have resistant gene Ph-3 and $06-9-62A{\times}06-9-62A$ were highly resistant to late blight. These highly resistant lines can be used as resources of resistance to late blight in a tomato breeding program in future.