• Research in Plant Disease
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• v.28 no.3
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• pp.172-178
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• 2022

The graft cactus (Gymnocalycium mihanovichii) continues to be exported to more than 20 countries worldwide. In April 2021, typical bacterial symptoms of soft rot were observed in the graft cactus (cv. Yeonbit) in Goyang, Gyeonggi-do, Korea, resulting in economic losses in cactus production. The stems turned dark brown and the flowers were covered with black rot. The bacterial strain designated as KNUB-01-21 was isolated from infected stems and flowers. The results of the morphological and biochemical tests of the isolate were similar to those of Pectobacterium brasiliense. For molecular analysis, the 16S rRNA region and three housekeeping genes (dnaX, leuS, and recA) of the strain KNUB-01-21 were amplified. Based on the results of the molecular analysis and morphological and biochemical tests, KNUB-01-21 was identified as P. brasiliense. The pathogenicity of KNUB-01-21 on graft cactus was confirmed by an inoculation test. Artificial inoculation using P. brasiliense KNUB-01-21 produced soft rot symptoms on the grafted cactus, and the same bacterium was re-isolated and re-identified. This is the first report of P. brasiliense causing soft rot in graft cactus in Korea.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.242-245
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• 2000

In 1999 and 2000, a rot of graft-cacti including Hylocereus trigonus (three-angled cactus), Gymnocalycium mihanovichii, and Chamaecereus silvestrii occurred in several greenhouses in major cactus-growing areas of Korea. Typical symptoms included a moist, light brown rot or a watery rot of the stems. A Colletotrichum sp. was isolated from the lesions. The fungus formed dark gray, dense or floccose colonies on potato dextrose agar, frequently forming many light pink acervuli often surrounded with setae. The hyaline, cylindrical conidia were one-celled with round ends. Appressoria were mostly semicircular or clavate. Thin-walled asci contained eight, one-celled, hyaline ascospores (biseriate in ascus). Ascopspores were strainht or curved, ellipsoidal or subcylindrical. Based on these characteristics, the fungus was identified as Glomerlla cingulata (anamorph : C. gloeosporioides). Wound inoculation of basal stems of the cactus by the mycelial plugs or conidia produced symptoms identical to those described above. Various cactus species were compared in susceptibility using stem disc inoculation. Cereus tetragonus, Eriocereus jusbertii, Myrtillocactus geomentrizans, and three-angled cacti from Mexico and Taiwan were susceptible, but C. peruvianus (Peruvian apple cactus) and Harrisia tortuosa not. This is the first report of G. cingulata causing stem rot of graft-cactus in Korea.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.314-317
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• 2007

A soft stem rot disease was observed on Chamaecereus silvestrii (Korean name: Sanchui), a scion of graft-cactus, in major growing areas of Suwon (National Horticulture Research Institute), Anseong, Eumseong, Cheonan, Daegu, and Goyang, Korea during 2000 and 2001. Typical symptoms were soft rots characterized by moist and watery decay of the whole cactus stem, which initiated as small water-soaked lesions and enlarged rapidly to the entire stem. The causal organism isolated from the infected stems was identified as Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora subsp. carotovora) based on its physiological and biochemical characteristics and confirmed by the cellular fatty acid composition and Biolog analyses. Artificial inoculation of the bacterium produced the same soft rot symptoms on the cactus stems, from which the same bacterium was isolated and identified. This is the first report of the P. carotovorum subsp. carotovorum in the graft-cactus C. silvestrii in Korea.

• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.546-549
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• 2015

This study was carried out to investigate the effect of simple hydroponic culture in cultivation of grafted cactus. The results obtained are as follows: Growth indexes of grafted cactus cultivars, such as scion diameter, fresh weight, and scion hardness were improved in simple hydroponic culture compared with soil culture regardless of cultivars. Stem rot and rate of non-graft take were lower in simple hydroponic culture than in soil culture, but no significant difference was monitored between cultivars. Time for harvesting was fast in simple hydroponic culture compared with soil culture. Marketable yield increased in simple hydroponic culture.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.525-528
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• 2008

A new graft cactus (Copiapoa scopa) cultivar 'Redstone' was developed at Cactus Research Institute, Gyeonggi-do A.R.E.S, in 2007. GCP563 and GCP618 were crossed in 2004 and we got 9 seedlings from this combination. After pedigree selection in 2005, one cultivar was finally selected through the test of specific character in 2007 and named as "Redstone". "Redstone" cultivar has red brown color and round globose shape with 15 ribs and its spines are black. This cultivar is able to produce 26.8 offshoots per plant. 'Redstone' cultivar has higher productivity and more slow growth than Copiapoa scopa cultivar.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.521-524
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• 2008

A new graft cactus (Chamaecereus silvestrii f. variegata) cultivars "Yellow Ttree" was developed at Cactus Research Institute, Gyeonggi-do A.R.E.S. in 2007. GC013001 and GC0110703 were crossed in 2005 and we got 42 seedlings from this combination. After pedigree selection in 2005, one cultivar were finally selected through the test of specific character in 2007 and named as "Yellow Ttree". "Yellow Ttree" has cylindrical shape of yellow color with 13~14 ribs. Formation of its offshoots is concentrated on the lower part of the plant. This cultivar is able to produce 13.9 offsets shoots per plant and its offshoots are hard.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.80-82
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• 2010

A stem spot disease was observed on Gymnocalycium mihanovichii (Korean name: Bimoran), a scion of graftcactus, in major growing areas of Goyang and Eumseong, Korea during 2008 and 2009. Typical symptoms were initial blackish brown lesions produced mainly on areoles and scars of injured stem tissues, gradually becoming large black spots. A causal organism isolate CD2-7A isolated from the infected stems was identified as Alternaria alternata based on its morphological characteristics and confirmed by the DNA sequencing analysis of ITS, glyceraldehydes-3-phosphate dehydrogenase (gpd), and allergen Alt a1 (Alt a 1) genes. Artificial inoculation of the fungal isolate CD2-7A produced the same rot symptoms on the cactus stems, from which the same fungus was isolated and identified. This is the first report of the black spot caused by A. alternata in the grafted cactus.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.50.2-50
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• 2002

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.16.2-16
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• 2000

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.321-324
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• 2008

A new yellow graft cactus Gymnocalycium mihanovichii ${\times}$ marsoneri cv. 'Hangseong' was developed by the National Institute of Horticultural &Herbal Science, Rural Development Administration in 2005. 'Hangseong' was selected from a interspecific crossing between Gymnocalycium mihanovichii and G. marsoneri. In 1998, 2 lines of '9834024' and '9834036' were selected from a crossing between G. mihanovichii 'IG-124' and G. marsoneri 'IG-223'. The 2 lines were crossed between them. In 2001, progenies produced from a crossing of the 2 lines were nursed and, finally yellow colored 'Wonkyo G1-169' was selected through 3 times of characteristic trials. It was named as 'Hangseong' and applied for a variety protection. Characteristics of 'Hangseong' is as follows: The color of body and tubercles is yellow. The shape of glove is flat with 7 to 9 deep ribs. Spine is medium straight with long size and brown color. Growth is fast as to reach 49.5 mm in diameter at 10 month after planting. Propagation ability is good as to set as many as 7.2 tubercles. 'Hangseong' is suitable for export to European countries or America. Characteristics of the cultivar can be maintained by vegetative propagation.