Ginseng root rot caused by Cylindrocarpon destructans is the most destructive disease of ginseng. Six different fungicides (thiophanate-methyl, benomyl, prochloraz, mancozeb, azoxystrobin, and iprodione) were selected to evaluate the inhibitory effect on the mycelial growth and conidial germination of C. destructans isolates. Benomyl and prochloraz were found to be the most effective fungicides in inhibiting mycelial growth of all tested isolates, showing 64.7% to 100% inhibition at a concentration of 10 µg/mL, whereas thiophanate-methyl was the least effective fungicide, showing less than 50% inhibition even at a higher concentration of 100 µg/mL. The tested fungicides exhibited less than 20% inhibition of conidium germination at concentrations of 0.01, 0.1, and 1 µg/mL. However, the inhibition effect of mancozeb on condium germination of C. destructans was significantly increased to 92% to 99% at a higher concentration of 100 µg/mL, while the others still showed no higher than 30% inhibition.
Benomyl ; Fungi* ; Germination* ; Panax* ; Spores, Fungal ; Thiophanate

In the present study we first report in Korea the identification and characterization of Fusarium oxysporum isolated from rotten stems and roots of paprika (Capsicum annuum var. grossum) at Masan, Kyungsangnamdo in 2006. The fungal species produced white aerial mycelia accompanying with dark violet pigment on PDA. The optimal temperature and pH for the growth of the species was 25degrees C and pH 7, respectively. Microscopic observation of one of isolates of the species shows that its conidiophores are unbranched and monophialides, its microconidia have oval-ellipsoidal shape with no septate and are of 3.0~11 x 1.5~3.5 microm sizes, its macroconidia are of 15~20 x 2.0~3.5 microm sizes and have slightly curved or slender shape with 2~3 septate. The results of molecular analysis show that the ITS rDNA of F. oxysporum from paprika shares 100% sequence identity with that of known F. oxysporum isolates. The identified species proved it's pathogenicity by causing rotting symptom when it was inoculated on paprika fruits. The growth of F. oxysporum from paprika was suppressed on PDA by agrochemicals such as benomyl, tebuconazole and azoxystrobin. The identified species has the ability of producing extracelluar enzymes that degrade cellobiose and pectin.
Agrochemicals ; Benomyl ; Capsicum* ; Cellobiose ; DNA, Ribosomal ; Fruit ; Fusarium* ; Gyeongsangnam-do ; Hydrogen-Ion Concentration ; Korea* ; Viola ; Virulence