• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.365-378
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• 2018

Anthracnose caused by Colletotrichum gloeosporioides, which is one of the major diseases of red dates, causes severe damages in jujube (Zizyphus jujuba Miller) production in Korea. This study was done to evaluate the inhibition of anthracnose occurrence and pathogen growth by the treatment of environment-friendly materials such as a Bordeaux mixture and loess-sulfur mixture and by defense-response signaling in jujube. The in vitro test of the environment-friendly materials and signaling molecules that were routinely applied did not exhibit any antifungal activities against the pathogen for jujube anthracnose. The Bordeaux mixture and loess-sulfur mixture at a two-fold concentration showed inhibition zones that were 16.0 and 20.3 mm in diameter, respectively. In the pathogen inoculation test with detached jujube tree leaves, while treatment with the environment-friendly materials diluted by half showed no inhibition of lesion development, they did show inhibition of lesion development when they were routinely applied to the leaves. In detached jujube fruits inoculated with the pathogen, better suppressive effects by the treatment of the environment-friendly materials were seen in the fruits at a young stage rather than in the ripening stage. The in vivo test with jujube trees in pots showed that the treatment of salicylic acid (1 mM) resulted in the best suppressive effects against lesion development. The results suggest that it is possible to manage the incidence of anthracnose by the treatment of environment-friendly materials such as the Bordeaux and loess-sulfur mixtures and signaling chemicals such as ethephon, hydrogen peroxide, methyl jasmonate, and salicylic acid in jujube trees and fruits. Consequently, these findings suggest that environment-friendly materials and defense response signaling molecules could be used as suitable candidates for sustainable agrochemicals to manage anthracnose in jujube production.

• Research in Plant Disease
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• v.25 no.4
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• pp.188-195
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• 2019

Among 6 fungicides, fluazinam, which had an excellent inhibitory effect on mycelial growth and spore germination, was also effective in controlling jujube anthracnose in the field. While EC₅₀ values of metconazole and tebuconazole ranged from 0.2 to 0.9 ㎍/ml and from 0.4 to 1.1 ㎍/ml against the mycelial growth, respectively, each inhibitory effect on spore germination was low by 7.4% and 11.1% at 50.0 ㎍/ml. In the field test, they showed the control value of 80.5% and 77.0%, respectively. The protective fungicides, as mancozeb and folpet, which had a low inhibitory effect on the mycelial growth, but had a high inhibitory effect of spore germination, showed excellent disease control activities by 87.6% and 92.0% in the field. Showing a result of resistance monitoring conducted with the isolates of Colletotricum gloeosporioides, the resistance against carbendazim was already generated in the field, but it was thought that there was no resistance to pyraclostrobin, fluazinam and tebuconazole. However, if the resistance factor value of the population of C. gloeosporioides isolates to pyraclostrobin was high by 160.4, the diversity of the response to the fungicide in the population was high, so it should be taken more attention to the resistance management.

• Research in Plant Disease
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• v.10 no.2
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• pp.130-134
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• 2004

The pathogenesity of 25 isolates of Colletotrichum gloeosporioides from apple, 42 isolates from pepper, 5 isolates from jujube, 8 isolates from persimmon was evaluated to know transmission to strawberry from other infected plants. Followings are the results. Colony morphology and spore size on potato dextrose agar was similar. When each isolate was inoculated on leaf and petiole of strawberry, isolates from persimmon was the most pathogenic. Five isolates, one pathogenic isolate per each host, were evaluated in simulated field condition under natural rainfall for their natural infectivity. All isolates infected strawberry in field condition, so C. gloeosporioides from other hosts are potential inoculum source of strawberry anthracnose.

• Research in Plant Disease
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• v.29 no.4
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• pp.345-362
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• 2023

Anthracnose, caused by the Colletotrichum genus, comprises a significant number of plant pathogens and poses a major threat to fruit production worldwide, including South Korea. Colletotrichum species were identified associated with anthracnose in fruits such as apple, persimmon, plum, peach, jujube, walnut, and grape. A polyphasic approach, including morphology, multigene phylogenetics, and pathogenicity testing, was used. Additionally, the in-vitro sensitivity of identified Colletotrichum species to common fungicides was also evaluated. A total of nine Colletotrichum species within two complexes, namely gloeosporioides and acutatum, have been identified as the causal agents of anthracnose in common fruits in South Korea. In the gloeosporioides complex, we found Colletotrichumaenigma, C. fructicola, C. gloeosporioides, C. horii, C. siamense, and C. viniferum. Meanwhile, in the acutatum complex, C. fioriniae, C. nymphaeae, and C. orientalis were identified. Notably, C. fructicola, C. siamense, C. fioriniae, and C. nymphaeae were reported for the first time from apple, C. siamense, C. fioriniae and C. nymphaeae from plum, C. siamense, C. fructicola, and C. fioriniae frompeach, C. siamense and C. horii from persimmon, C. fioriniae from Omija (Schisandra), C. orientalis from walnut, C. nymphaeae from jujube, and C. aenigma, C. fructicola, and C. siamense fromgrape. Fungicide sensitivity tests revealed significant variation in the EC₅₀ values among specific Colletotrichum species when exposed to different fungicides. Moreover, the same Colletotrichum species isolated from different host plants displayed varying sensitivity to the same fungicide.