Occurrence of Sclerotinia Rot in Cruciferous Crops Caused by Sclerotinia spp. |
Wan Gyu Kim, Weon Dae Cho |
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Abstract |
Cruciferous crops grown in greenhouses and fields in Korea were surveyed from 1995 to 2000. Sclerotinia rot most severely occurred up to 30% in cabbage. Incidence of the disease was as high as 20% at its maximum in Chinese cabbage and rape and 10% in radish, but as low as less than 1 or 2% in broccoli and kale. Symptoms of Sclerotinia rot commonly developed on leaves and stems of the crucifers, but rarely on rachises of broccoli. A total of 112 isolates of Sclerotinia species was obtained from the diseased crucifers. Out of the isolates, 103 isolates were identified as S. sclerotiorum, and the rest as S. minor based on their morphological and cultural characteristics. S. sclerotiorum was isolated from all the crucifers, while S. minor was isolated from Chinese cabbage, broccoli, and kale. Six isolates of S. sclerotiorum and three isolates of S. minor were tested for their pathogenicity to the crucifers by artificial inoculation. All the isolates of the two Sclerotinia spp. induced rot symptoms on the plants of the crucifers tested, which were similar to those observed in the fields. The pathogenicity tests revealed that there was no significant difference in the susceptibility of the crucifers to the isolates of S. sclerotiorum. However, in case of S. minor, radish was relatively less susceptible to the pathogen. |
Key Words:
Crucifer, pathogenicity, Sclerotinia rot, Sclerotinia sclerotiorum, S. minor |
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