• The Plant Pathology Journal
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• 제26권3호
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• pp.231-237
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• 2010

The heat-inactivated (at $121^{\circ}C$ for 20 min) conidial suspension of Bipolaris cactivora (HICS) was evaluated for the control of Bipolaris stem rot of cactus caused by B. cactivora. Severe rot symptoms were developed on the cactus stem discs inoculated with B. cactivora from 5 days after inoculation. However, only small brownish spots developed on the stem discs treated with HICS 2 days prior to the pathogen inoculation. HICS also reduced symptom development on cactus stem discs inoculated with other fungal pathogens such as Alternaria alternata, Colletotrichum gloeosporioides, and Fusarium oxysporum, suggesting its disease-inhibitory efficacy may not be pathogen-specific. HICS significantly reduced severities of the stem rot disease on several cactus species including Hylocereus trigonus, Cereus peruvianus, Chamaecereus silvestrii and Gymnocalycium mianovichii, but not on Cereus tetragonus. Extensive wound periderms were formed in the stem tissues of inoculation and/or wounding sites on C. peruvianus treated with HICS alone or prior to the pathogen inoculation, but not on C. tetragonus, indicating the structural modifications may be related to the mechanism of disease suppression by HICS. HICS also reduced the disease development on the grafted cactus (H. trigonus stock and G. mianovichii scion) with the control efficacy nearly equivalent to the application of a commercial fungicide. All of these results suggest HICS can be used as an environmental-friendly agent for the control of the cactus stem disease.

• Journal of Biosystems Engineering
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• 제41권3호
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• pp.201-207
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• 2016

Purpose: A water-spraying type automatic glochids removal system for cactus (Opuntia humifusa) stem was developed, and its performance was evaluated. The system was developed to reduce intensive human labor in removing glochids from cactus stem skin without inducing damage prior to further processing into value-added products. Methods: The developed system consists of conveyor and water-spraying systems. The conveyor system delivers cactus stems through water-spraying compartments and finally to a collecting box. In order to remove the glochids, rotating nozzles spray water over all areas (i.e., front and back faces and sides) of the cactus skin under controlled water pressure. Operating conditions such as conveyor speed, water pressure, angle of water-spraying nozzles, distance between conveyor belt and rotating nozzles, and angle of cactus flipping slide were adopted from our previous study and applied on the system design and manufacturing. The performance of glochids removal was evaluated by counting the number of glochids on the cactus stem before and after processing on the system. Results: The developed system performed efficiently and effectively under the pre-studied operating conditions except for the angle of cactus flipping slide. The new system had a glochids removal ratio of 94.1% without damaging the cactus skin. Considering the original number (approximately 30-60) of glochids, the remaining number was low (1-4), and most of them were found at the side edge of the cactus stem. This system can remove glochids from 360 cactus stems in 1 hr regardless of cactus size. Conclusions: The performance of the new system in glochids removal without damaging cactus skin is superior to any other existing device (i.e., brush type, rubber-friction type, and agitation type). The system is expected to be applied in cactus (O. humifusa) processing facilities.

• 한국건설순환자원학회논문집
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• 제8권3호
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• pp.365-371
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• 2020

본 연구에서는 열매를 수확한 후 폐기되는 손바닥 선인장 줄기를 재활용하기 위하여 선인장 줄기 분말을 시멘트계 재료의 혼화제로 적용하고자 하였다. 이를 위해 선인장 줄기 분말을 혼입한 모르타르의 굳지 않은 특성과 강도에 대한 연구를 수행하였다. 또한 그 결과를 기존의 당류계 혼화제인 지연제 설탕과 증점제 메틸셀룰로오스를 혼입한 모르타르의 특성과 비교하였다. 연구 결과, 선인장 줄기 분말은 지연제로서 효과를 뚜렷하게 보여주지 못하였다. 반면, 선인장 줄기 분말 혼입율이 증가할수록 플로 및 공기량이 메틸셀룰로오스를 혼입한 모르타르와 유사한 경향을 나타내어 증점제로서 활용 가능성을 확인하였다. 또한 선인장 줄기 분말의 혼입율이 0.3% 이내일 때에는 모르타르의 강도가 증가하는 것으로 나타났다.

• 식물병연구
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• 제7권1호
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• pp.56-59
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• 2001

Stem rot of cacti was found at major cultivating areas including Koyang, Ansung and Eumsung of Korea in 2000. Bipolaris cactivora was consistently isolated from the lesions. The disease occurred on different species of cactus including Cereus peruvianus, C. neopithahaja f. monstruo년, C. tetragonus, Chamaeceresu silestrii, Ch. silvestrii, f. variegata, Gymnocalcium mihanovichii var. friedrichii. G. denudatum var. pentacantha, Hylocereus trigonus and Isolatocereus dumortier. Major symptoms on the cactus species except H. trigohus were almost identical. A rapid rot of the upper portion of the catus stem appeared, and became blackened and somewhat dry. On H. trigonus, the symptom was initially light yellow, water-soaked lesion, turned into light brown and dried to death. According to pathogenicity test, 10 out of 16 cactus species and varieties tested produced identical symptoms as found in the field. However, the fungi did not show pathogenicity to Notocactus scopa, Echinocactus grusonii, Eriocactus leninghausii, Lobivia nealeana, Mammillaria elongata var. intertexta.

• 한국수산과학회지
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• 제52권4호
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• pp.358-365
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• 2019

This study investigated the effects of dietary cactus Opuntia ficus-indica stem and fruit extract on the growth, flesh quality, lysozyme activity, and histological changes of growing Korean rockfish Sebastes schlegeli. Three replicates of fish (152 g/fish) were fed one of the following diets: containing 0 additions (control); 0.1, 0.5, or 1.0% cactus stem powder; or 1.0% fruit extract for 11 weeks. Growth performance did not differ significantly among treatments, including survival, final weight, feed efficiency, and daily feed intake. The experimental diets did not affect the proximate and fatty acid compositions, plasma biochemistry, or dorsal muscle texture of the fish. However, the plasma lysozyme activity of the fish fed the diet containing 0.1% cactus stem was significantly higher than that of the fish fed the control diet. These fish had variously sized lipid vacuoles in the liver tissue compared with the control. Distinct mucosal folds and mucus-secreting goblet cells developed in the fish fed the diet containing 1% cactus stem compared with the other dietary groups. These results suggest that feeding growing Korean rockfish cactus stem might increase the plasma lysozyme activity and induce histological changes in the gastrointestinal tract that might be related to digestion.

• The Plant Pathology Journal
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• 제16권4호
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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.

• 한국식물병리학회지
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• 제14권5호
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• pp.463-466
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• 1998

A Fusarium species was isolated from stems of cactus(Hylocereus trigonus) showing rot symptoms at Koyang, Kyonggi province in 1997. This pathogen was identified as Fusarium oxysporum based on mycological characteristics. The rot symptom appeared at the soil line and roughly circular lesions, 1∼3 mm in diameter, appeared on basal stems. The pathogen formed both microconidia and macroconidia. Microconidia were formed abundantly in false-heads on short monophialides, oval to kidney-shaped. Macroconidia were slightly sickle-shaped, 3∼5-septated with an attenuated apical cell and a foot-shaped basal cell. Colony color on PDA was white, peach or purple. Chlamydospores were formed abundantly on PDA. The pathogen was able to cause stem rot symptoms to cactus by wound inoculation as well as non-wound inoculation.

• The Plant Pathology Journal
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• 제29권1호
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• pp.42-51
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• 2013

One of the most important limiting factors for the production of the grafted cactus in Korea is the qualitative and quantitative yield loss derived from stem rots especially caused by Bipolaris cactivora. This study is aimed to develop microbial control agents useful for the control of the bipolaris stem rot. Two bacteria (GA1-23 and GA4-4) selected out of 943 microbial isolates because of their strong antibiotic activity against B. cactivora were identified as Bacillus subtilis and B. amyloliquefaciens, respectively, by the cultural characteristics, Biolog program and 16S rRNA sequencing analyses. Both bacterial isolates significantly inhibited the conidial germination and mycelial growth of the pathogen with no significant difference between the two, of which the inhibitory efficacies varied depending on the cultural conditions such as temperature, nutritional compositions and concentrations. Light and electron microscopy of the pathogen treated with the bacterial isolates showed the inhibition of spore germination with initial malformation of germ tubes and later formation of circle-like vesicles with no hyphal growth and hyphal disruption sometimes accompanied by hyphal swellings and shrinkages adjacent to the bacteria, suggesting their antibiotic mode of antagonistic activity. Control efficacy of B. subtilis GA1-23 and B. amyloliquefaciens GA4-4 on the cactus stem rot were not as high as but comparable to that of fungicide difenoconazole when they were treated simultaneously at the time of pathogen inoculation. All of these results suggest the two bacterial isolates have a good potential to be developed as biocontrol agents for the bipolaris stem rot of the grafted cactus.

• 한국식물병리학회지
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• 제14권6호
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• pp.661-663
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• 1998

Bipolaris stem rot of cactus severely occurred up to 77% at the field of Koyang and Kimcheon from 1996 to 1997. The symptom was initially light yellow, water soaked round lesion, subsequently turned light brown and dried to death. The causal fungus was identified as Bipolaris cactivora (Petrak) Alcorn. Conidia were obclavate to fusoid, rounded ends, light brown color, 1~4 septate, and conidial size was 23~42$\times$6~9 ${\mu}{\textrm}{m}$ (av. 32.5$\times$7.5 ${\mu}{\textrm}{m}$). Conidiophores were caespitose, straight, pale to golden brown and 67~280 ${\mu}{\textrm}{m}$ in length. When healthy cacti were inoculated with the isolates obtained form the lesion of diseased plants, the same characteristic symptoms as those in the field were produced. The symptom of four-month-old cactus was developed more rapidly than that of six-month-old cactus. The pathogen was reisolated from the artificially inoculated lesions.

• The Plant Pathology Journal
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• 제23권4호
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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.