• 한국산림과학회지
• /
• 제55권1호
• /
• pp.22-29
• /
• 1982

美國에서 Pisolithus tinctorious(P.t.), Thelephora terrestris(T.t.)의 두 가지 외생균근균(外生菌根菌)을 도입(導入)하여 한국(韓國)에 있는 5개(個) 소나무수종(樹種)에 인공접종(人工接種)하여 그들의 생장촉진효과(生長促進効果)를 측정(測定)하였다. P.t.와 T.t.균계(菌系)를 대량증식배양(大量增殖培養)하여, 파종(播種) 직전(直前)에 Methyl bromide로 훈증(薰蒸)된 토양(土壤)에 접종(接種)하였다. 생장(生長) 첫해에, P.t.로 접종(接種)한 Pinus densiflora, P. thunbergii, P. rigida, P. rigida${\times}$taeda묘목(苗木)은 무처리묘목(無處理苗木)보다 수고생장(樹高生長)이 각각(各各) 55%, 36%, 69%, 37% 증가(增加)되었다. P. densiflora, P. rigida${\times}$taeda묘목(苗木)의 건중량(乾重量)에서는 P.t. 접종묘(接種苗)가 무처리묘목(無處理苗木)보다 각각(各各) 143%, 128% 증가(增加)되었다. 그러나 P. koraiensis에서는 생장(生長) 첫해에 균근균접종효과(菌根菌接種効果)가 나타나지 않았고 접종(接種)된 5개수종(個樹種)에서 T.t. 접종효과(接種効果)는 없었다. 우수(優秀)한 균근균(菌根菌)을 선발(選拔)하여 묘포장(苗圃場)에 인공접종(人工接種)할 경우 파종묘(播種苗)의 초기생장(初期生長)이 촉진(促進)되고, 묘목(苗木)의 품질향상(品質向上)을 도모(圖謀)할 수 있다고 결론(結論)지을 수 있다. 맹폐지조림시(荒廢地造林時) P.t.균(菌)의 이용(利用)에 관(関)하여서도 토의(討議)하였다.

• The Plant Pathology Journal
• /
• 제18권5호
• /
• pp.293-299
• /
• 2002

A survey of Fusarium wilt of perilla was conducted in 12 locations in Korea from 1999 to 2001. The disease occurred in 74 out of 187 fields in the 12 locations surveyed, and incidence of the disease reached up to 30% at its maximum in some perilla fields in Seosan and Dangjin. Incidence of the disease in the other locations ranged from 0.2 to 20%. A total of 327 isolates of Fusarium spp. were obtained from stems and roots of the diseased perilla plants. The isolates were identified based on their morphological characteristics. Out of the 327 isolates of Fusarium, 277 isolates from 12 locations were identified as F. oxysporum, 11 isolates from three locations as F. solani,17 isolates from two locations as F. equiseti, 4 isolates from one location as F. avenaceum and 6 isolates from one location as F. subglutinans. The other 12 isolates of Fusarium from four locations were unidentified. Twelve isolates of F. oxysporum and two isolates each of the other Fusarium spp. were tested for their pathogenicity to five cultivars of perilla. Seven isolates of F. oxysporum were strongly pathogenic to some perilla cultivars, but the other five isolates were weakly or not pathogenic. One isolate of F. solani was strongly pathogenic to all the perilla cultivars tested, but another isolate was not pathogenic. All the isolates of F. equiseti, F. avenaceum, and F. Subglutinans tested were not pathogenic to any of the perilla cultivars tested. Symptoms on the perilla plants induced by artificial inoculation with strongly pathogenic isolates of F. oxysporum and F. solani appeared as wilt, stem blight, and root yet, which were similar to those observed in the fields. The isolates which induced symptoms by artificial inoculation were re-isolated from the lesions of the perilla plants inoculated. All the isolates of F. oxysporum tested were not pathogenic to eight other crops inoculated. Results of this study reveal that F. oxysporum is the main pathogen of perilla wilt and that it is host specific to perilla. forma specialis of F. oxysporum causing wilt of perilla is proposed as perillae.

• Parasites, Hosts and Diseases
• /
• 제47권3호
• /
• pp.307-310
• /
• 2009

Fishborne trematode (FBT) metacercariae were investigated in yellowfin goby, Acanthogobius flavimanus, collected from Shinan-gun and Muan-gun, Jeollanam-do (province), Korea. All collected fishes were examined using the artificial digestion method. In all of 15 gobies from Aphae-myeon in Shinan-gun, metacercariae of Stictodora spp. (334 metacercariae/fish), Heterophyes nocens (153/fish), and Heterophyopsis continua (20/fish) were detected. In 2 of 14 gobies from Jido-myeon in Shinan-gun, 8 Echinostoma hortense metacercariae in total were detected. In 15 gobies from Haeje-myeon in Muan-gun, the metacercariae of H. continua were found in 100%, Stictodora spp. in 86.7%, and H. nocens in 6.7% of fish examined. The average numbers of metacercariae per infected fish were 23.3 (H. continua), 416.0 (Stictodora spp.), and 2.0(H. nocens), respectively. The metacercariae of E. hortense found in gobies were elliptical, with 150 ${\times}$ 138 ${\mu}m$, in average size, and had 27 collar spines on the head crown. The above results suggest that yellowfin gobies from 2 localities may be the potential infection sources of FBT. Moreover, it is proved for the first time that the yellowfin goby, A. flavimanus, acts as a second intermediate host for E. hortense.

• 한국작물학회지
• /
• 제57권4호
• /
• pp.389-396
• /
• 2012

Melon (Cucumis melo) is an annual herbaceous plant of the family Cucurbitaceae. Phytophthora rot, caused by Phytophthora capsici is a serious threat to cucurbits crops production as it directly infects the host plant, and it is difficult to control because of variable pathogenicity. This study investigated the resistance of 450 accessions of melon germplasm against Phytophthora rot by inoculating the seedlings with sporangial suspension ($10^{5\;or\;6}$ zoosporangia/ml) of P. capsici. Disease incidence of Phytophthora rot was observed on the melon germplasm at 7-day intervals for 35 days after inoculation. Susceptible melon germplasm showed either severe symptoms of stem and root rot or death of the whole plant. Twenty out of 450 tested accessions showed less than 20% disease incidence, of which five accessions showed a high level of resistance against Phytopthtora rot. Five resistant accessions, namely IT119813, IT138016, IT174911, IT174927, and IT906998, scored 0% disease incidence under high inoculum density of P. capsici ($10^6$ zoosporangia/mL). We recommend that these candidate melon germplasm may be used as genetic resources in the breeding of melon varieties resistant to Phytophthora rot.

• Parasites, Hosts and Diseases
• /
• 제56권1호
• /
• pp.41-48
• /
• 2018

The infection status of Clonorchis sinensis metacercariae (CsMc) was examined in freshwater fish from a highly prevalent site, Wicheon (a branch of Nakdong-gang), which is located in Gunwi-gun, Gyeongsangbuk-do, the Republic of Korea. Total 1,162 fish in 32 species were examined by the artificial digestion method through 6 years. CsMc were detected in 720 (67.5%) out of 1,067 fish (26 spp.) and their density was 610 per fish infected. In the susceptible gobioninid fish group, i.e., Pungtungia herzi, Squalidus gracilis majimae, Squalidus japonicus coreanus, Sarcocheilichthys variegatus wakiyae and Pseudorasbora parva, all of 323 fish were infected with an average of 1,310 CsMc. Total 23 (95.8%) gobioninid fish, i.e., Pseudogobio esocinus, Abbottina springeri, Hemibarbus longirostris, Microphysogobio koreensis, and Microphysogobio jeoni, were infected with 127 CsMc in average. In the acheilognathinid fish (bitterlings) group, the prevalence was 77.0%, and the density was 50 CsMc per fish infected. In the rasborinid fish (chubs) group, i.e., Zacco platypus, Zacco temminckii, Zacco koreanus, and Opsariichthys uncirostris amurensis, 147 (36.5%) out of 403 fish examined were infected with 15 CsMc in average. The susceptibility indices of CsMc were 412 in the overall positive fish group, 1,310 in the gobioninid group-1, 122 in the gobioninid group-2, 38.5 in the acheilognathinid group, and 5.5 in the rasborinid fish group. Conclusively, it was confirmed that CsMc are highly prevalent in fish from Wicheon, and their infection tendency varied according to the subfamily groups in Cyprinidae fish hosts.

• The Plant Pathology Journal
• /
• 제26권1호
• /
• pp.63-69
• /
• 2010

The effect of Acibenzolar-S-methyl (ASM) and Rahnella aquatilis Ra39 against apple fire blight disease caused by Erwinia amylovora were tested as a possible alternative to streptomycin. In vitro studies, no inhibition effect against the pathogen was found when ASM was tested. Under greenhouse conditions, application of R. aquatilis Ra39 with the highly susceptible M26 rootstock resulted in a marked disease suppression. Application of ASM and strain Ra39 caused a high decrease of the disease, 82% and 58% respectively; this was correlated with a reduction of the growth of the pathogen within host plants up to 64% and 49.5% respectively. Further studies in the field under artificial infection condition during full bloom revealed that application of ASM and R. aquatilis Ra39 with Gala variety resulted in a control effect up to 21 and 29% respectively. In physiological studies, enhanced activities of PR-proteins (chitinase and $\beta$-1, 3-glucanase) were detected, which are well known as biochemical markers for systemic acquired resistance. Application of ASM to apple shoots caused the highest chitinase activity followed by strain Ra39. The enzyme activity was increased after 2, 4 and 6 days from application. In addition, ASM-treatment caused the higher $\beta$-1, 3-glucanase activity than strain Ra39. Maximum enzyme activity was recorded after 6 days from application and then decreased after 8 and 10 days from application.

• 미생물학회지
• /
• 제40권2호
• /
• pp.115-120
• /
• 2004

시안세균(Anabaena cylindrica)의 생장을 효과적으로 억제하는 세균을 분리하여 NG-2로 구분하였다. 이 세균은 그람 음성의 막대형 세균으로서 1.3∼$1.8{\times}0.35{\mu}m$ 정도의 크기를 보였으며, 카탈라제와 옥시다제 양성 반응을 나타내었고, 35∼$40^{\circ}C$아 pH 9.0의 적정생장 조건을 보였다. A.cylindrica의 NG-2를 JM 배지에서 혼합배양할 경우 두 미생물군은 서로 반비례적으로 성장하였으며, 24시간 이내에 A. cylindrica의 영양세포가 거의 완전히 소멸하였다. NG-2는 빛이 있는 조건에서만 효과적으로 A. cylindrica를 분해하였는데, 이는 NG-2의 A. cylindrica 분해활성이 숙주의 광합성 작용에 매우 의존적임을 의미한다. 분리세균의 A. cylindlica 분해작용을 현미경으로 관찰한 결과 NG-2는 숙주세포에 부착하지 않고 배지 내에 산재한 상태에서 영양세포를 분해하였으며, 이형세포는 분해되지 않았다. 또한 영양세포의 세포벽이 분해되면 분해세균들이 filament 주위에 집중적으로 부착하는 콜로니를 형성함으로써 A. cylindrica를 완전히 분해하는 것이 확인되었다. A. cylindrica에 대한 NG-2의 분해활성은 인공배지 뿐만 아니라 강물에서도 유사한 결과를 나타내었다. 또한 발포 polystyrene 재질의 bead에 세균을 부착함으로써 A. cylindrica 분해 효율을 더 상승시킬 수 있었다.

• 식물병연구
• /
• 제21권1호
• /
• pp.32-35
• /
• 2015

2011년에 전북 정읍지역에 재배하는 쓴오이에서 탄저병이 발생하였다. 탄저병은 처음에 흑갈색의 작은 원형반점들이 잎과 열매에 나타났다. 감염된 잎과 열매는 작은 갈색-흑갈색 반점을 형성하고 병반이 커지거나 융합되어 큰 원형의 흑갈색 병반을 형성하였다. 탄저병 병징에서 분리한 병원균은 배양형태적 특성조사와 ITS rDNA 염기서열 분석결과 Colletotrichum gloeosporioides로 동정되었다. 분리된 C. gloeosporioides는 인공접종에 의한 병원성 검정에서도 동일한 병징을 나타내어 국내 처음으로 C. gloeosporioides에 의한 쓴오이 탄저병을 보고한다.

• Parasites, Hosts and Diseases
• /
• 제54권4호
• /
• pp.537-541
• /
• 2016

Stellantchasmus falcatus (Digenea: Heterophyidae) is first reported from Cambodia through recovery of the metacercariae from mullet fish and adult flukes from an experimentally infected hamster. We purchased 7 mullets, Chelon macrolepis, in a local market of Phnom Penh, Cambodia, and each of them was examined by the artificial digestion method on May 2010. The metacercariae of S. falcatus were detected in all mullets (100%) examined, and their average density was 177 per fish. They were elliptical, $220{\times}168{\mu}m$ in average size. They were orally infected to an hamster to obtain adult flukes. Adults recovered at day 10 post infection were observed with a light microscope and a scanning electron microscope (SEM). They were small, $450{\times}237{\mu}m$ in average size, had a small oral sucker ($41{\times}50{\mu}m$), subglobular pharynx ($29{\times}21{\mu}m$), slender esophagus ($57{\mu}m$), long and thick-walled expulsor ($119{\times}32{\mu}m$), spherical ovary ($58{\times}69{\mu}m$), and 2 ovoid testes (right: $117{\times}74{\mu}m$; left: $114{\times}63{\mu}m$). Eggs were small, yellow, and $23{\times}12{\mu}m$ in average size. In SEM observations, tegumental spines were densely distributed on the whole tegument, and single small type I sensory papillae were distributed around the lip of oral sucker. The small ventral sucker was dextrally located and had 8 type I sensory papillae on the left margin. It has been first confirmed in the present study that the mullet, C. macrolepis, is playing the role of a second intermediate host of S. falcatus in Cambodia.

• 식물병연구
• /
• 제19권2호
• /
• pp.118-120
• /
• 2013

2007년부터 2009년까지 전북 익산지역의 고구마 육묘장에서 봄에 Sclerotium rolfsii에 의한 고구마 흰비단병이 발생하였다. 초기증상은 황화되어 시들고 감염된 조직 주변과 지제부에 흰색의 균사체가 형성되었다. 육묘시기에는 병에 매우 약하여 감염되면 고사된다. 병원균은 배지 위에서 흰색균사가 빠르게 자라고 7일 후 균핵을 형성하였다. 균핵은 처음에 흰색에서 시간이 경과됨에 따라 갈색으로 변하였다. 따라서 고구마에서 발생한 병징, 병원균의 균학적 특징과 병원성을 검정한 결과, 이 병을 S. rolfsii Saccardo에 의한 고구마 흰비단병으로 동정하였다.