• The Plant Pathology Journal
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• v.25 no.4
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• pp.322-327
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• 2009

A total of 23 isolates of Botrytis cinerea causing the grey mold were collected from infected ginseng in several fields of Korea. The sensitivity to carbendazim and the mixture of carbendazim plus diethofencarb was determined through a mycelial inhibition test on PDA amended with or without fungicides. B. cinerea isolates were classified as 3 phenotypes, which were the first phenotype resistant to both of carbendazim and the mixture ($Car^RMix^R$), the second one resistant to carbendazim and sensitive to the mixture ($Car^RMix^S$), and the last one sensitive to both of them ($Car^RMix^S$). Carbendazim resistance correlated with a single mutation $\beta$-tubulin gene of B. cinerea amplified with primer pair tubkjhL and tubkjhR causing a change of glutamate to alanine at amino acid position 198. Furthermore, the substitution of valine for glutamate led the resistance to carbendazim and the mixture at the same position of amino acid. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis using the restriction endonuclease, Tsp451 and BstUI allowed differentiation of the PCR fragment of $\beta$-tubulin gene of $Car^SMix^S$ isolates from that of $Car^RMix^R$ and $Car^RMix^S$ isolates. This method will aid in a fast detection of resistance of carbendazim and the mixture of carbendazim plus diethofencarb in B. cinerea in ginseng field.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.49-56
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• 2010

Thirty-six isolates of Colletotrichum spp. were obtained from infected grapes in two different locations of Korea; 18 isolates from Cheonahn, where carbendazim (MBC) and the mixture of MBC and diethofencarb (NPC) had been applied to control grape ripe rot, and 18 isolates from Cheongju, where no fungicides had been used. Sequences analysis of the internal transcribed spacer (ITS) and the $\beta$-tubulin gene identified 34 of the 36 isolates as Colletotrichum gloeosporioides. The remaining two isolates from Cheongju were identified as C. acutatum. Of the 18 isolates from Cheonahn, 12 were resistant to both MBC and the mixture (MBC+NPC), and six were sensitive to them. All C. gloeosporioides isolates from Cheongju, but not the two C. acutatum isolates, were sensitive to these fungicides. Sequence analysis of the $\beta$-tubulin gene in all isolates revealed that C. gloeosporioides resistant to MBC and MBC+NPC had a tyrosine instead of phenylalanine at the amino acid position 200. The appearance of resistance to MBC and the mixture in C. gloeosporioides correlated with the history of fungicide application in Korea.