• Applied Biological Chemistry
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• v.40 no.5
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• pp.447-450
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• 1997

Eighteen N-substituted phenyl 1, 3, 5-trimethylpyrazole-4-carboxamides were synthesized to screen for their mycelial growth inhibition activity against Rhizoctonia solani $K{\ddot{u}}hn$ $(pEC_{50})$ and to measure enzymatic inhibition activity of these compounds $(pI_{50})$ against succinate dehydrogenase (SDH) isolated from Rhizoctonia solani $K{\ddot{u}}hn$ A structure-activity relationship formulated by regression analysis showed that 79% of the variance in mycelial growth inhibition activity can be explained with SDH inhibition activity and chromatographic capacity factor $(\acute{k})$ as a hydrophobic parameter related to the penetration and transport processes in the biological system.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.257-265
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• 1995

Morphological characteristics and pathogenicity of Rhizoctonia species causing blight diseases of turfgrasses were studied. The species were identified as Rhizoctonia cerealis Van der Hoeven, R. oryzae Ryker et Gooch, and R. solani $K{\ddot{u}hn}$ based on their morphological and cultural characteristics. Isolates of R. solani were assigned to anastomosis groups (AG) with cultural type 1 (1A), 2-2 (IIIB), and 2-2 (IV). R. cerealis, R. oryzae and R. solani induced sheath rot and foliar blight symptoms on creeping bentgrass (Agrostis palustris) and zoysiagrass (Zoysia japonica). Inoculation tests showed that disease severity with isolates of R. cerealis and R. oryzae were more serious to creeping bentgrass than zoysiagrass. AG 1(1A) isolates of R. solani were strongly pathogenic on creeping bentgrass, but moderate to zoysiagrass. AG 2-2 (III) isolates were moderately pathogenic to zoysiagrass, but weakly to creeping bentgrass. AG 2-2 (IV) isolates from zoysiagrass were moderately pathogenic to zoysiagrass, but weakly to creeping bentgrass.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.376-382
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• 2013

Rice sheath blight (ShB), caused by Rhizoctonia solani K$\ddot{u}$hn, is one of the serious fungal disease resulting in severe yield loss in rice field worldwide. There are limited sources of genetic resistance and no commercial cultivar with high level of ShB resistance is currently available in Korea. In order to seek available resources with high level of resistance to ShB, 40 rice germplasms were used to evaluate disease reactions including ShB, leaf blast and bacterial leaf blight and these germplasms also examined agronomic traits such as days to heading, culm length, panicle length, No. of panicles, No. of spikelets per panicle and so on. There is wide variation in agronomic characters and disease reactions. Rice germplasms also showed considerably different ShB reaction caused by inoculation at seedling stage. Areumbyeo, Gayabyeo, IR579-Es44 and IR64 showed more strong reaction to ShB than the others. Especially, Gayabyeo is considerably available to develop a new variety with resistance to ShB in Korea.