• Mycobiology
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• 제43권3호
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• pp.339-342
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• 2015

The use of microorganisms and their secreted molecules to prevent plant diseases is considered an attractive alternative and way to supplement synthetic fungicides for the management of plant diseases. Strain BS062 was selected based on its ability to inhibit the mycelial growth of Botrytis cinerea, a major causal fungus of postharvest root rot of ginseng and strawberry gray mold disease. Strain BS062 was found to be closely related to Streptomyces hygroscopicus (99% similarity) on the basis of 16S ribosomal DNA sequence analysis. Postharvest root rot of ginseng and strawberry gray mold disease caused by B. cinerea were controlled up to 73.9% and 58%, respectively, upon treatment with culture broth of Streptomyces sp. BS062. These results suggest that strain BS062 may be a potential agent for controlling ginseng postharvest root rot and strawberry gray mold disease.

• 한국균학회지
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• 제47권4호
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• pp.427-435
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• 2019

최근 경남 산청, 함양의 딸기 재배지역의 육묘하우스에서 딸기 묘목의 뿌리와 관부를 썩게 하고 지상부의 생육을 저해하며 최종적으로 식물체를 시들게 하는 뿌리썩음병(가칭)증상이 발생하였다. 이러한 병반을 나타내는 딸기 식물체 뿌리와 관부로부터 병원균을 분리하고 균학적 특성을 조사하였으며, 유전자 염기서열 분석과 계통학적 분석을 수행하였다. 그 결과, 딸기 육묘과정에서 발생한 뿌리썩음병(가칭)의 병원균은 Neopestalotiopsis clavispora로 확인되었으며, 건전한 딸기 식물체를 대상으로 접종실험을 수행한 결과 딸기에 대한 병원성을 확인하였다. 지금까지 국내에서 N. clavispora에 의한 딸기 뿌리썩음병이 보고되지 않았으므로 본 연구결과를 바탕으로 이병을 딸기뿌리썩음병으로 국내 최초로 보고한다.

• 원예과학기술지
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• 제34권2호
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• pp.242-248
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• 2016

This research was conducted to determine the effects of four different substrates, expanded rice hulls (ERH), commercial substrates for strawberries (CSS), clay sand (CS), and loamy sand (LS), on the inhibition of anthracnose crown rot (ACR) in strawberry. Mother plants of 'Seolhyang' strawberry were transplanted into an elevated bed in March, 2013 and March, 2014 and the runners connecting mother plants and daughter plants were cut in early August of both years. After separation, growth characteristics of the daughter plants were measured and then each daughter plant was inoculated with conidial suspensions of Colletotrichum fructicola, one of several species of Colletotrichum that causes ACR in strawberries. The incidence of ACR as influenced by the different substrates was investigated in both years. The daughter plants grown on CSS had the highest values for shoot height, leaf area, and fresh weight. Those grown on ERH and LS substrates also displayed good above-ground growth characteristics except for fresh weight, but the daughter plants grown on CS had the poorest above-ground growth characteristics. The ERH and CS treatments resulted in the highest number of primary roots and the greatest root weight. The CSS-grown daughter plants had the highest ACR disease index, followed by the CS and LS treatments, but there were no significant differences among the three substrates. However, the ERH-grown daughter plants had a markedly lower ACR disease index on October 11, 2013 and October 7, 2014. The CSS-grown daughter plants had high nitrogen and potassium contents and low calcium content, whereas the ERH-grown daughter plants had low nitrogen levels and high silicon levels. The results of this study provide basic information on the ability of the different substrates tested to provide disease suppression of ACR in the propagation of strawberry transplants.

• 한국식물병리학회지
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• 제14권5호
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• pp.445-451
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• 1998

A severe Phytophthora rot of strawberry caused by a species of Phytophthora has been widely occurred at major cultivation areas of Kimhae on August in 1997. Incidence of the disease was obtained in the range of 69.2~83.6% in surveyed 4 fields and showed an average of 75.2%. A species of Phytophthora was mostly isolated from the crown of infected strawberry plants and all the isolates were identified as P. nicotianae var. nicotianae (=P. parasitica). The fungus showed strong pathogenicity on strawberry by inoculation test. As a result of the leaf inoculation using mycelial disks of the fungus, both leaves and petioles were darkly browned, and were finally blighted. As a result of the root inoculation of zoospore suspension, both roots and crowns were rotten with dark brown. Although the fungus produced sporangia either on V-8 juice agar medium or liquid medium, the sporangia observed on the liquid medium appeared to be broadly turbinate and noncaducous. Moreover the fungus cultured on the liquid medium often produced sporangia having two papilla. The number of zoospores in sporangia was found to be ranged from 3 or 4 to as many as 20 or 25. In addition, the released zoospore from the sporangium became the cystospore during the prolonged culture of the fungus. The sporangia were measured as av. 49$\times$35 ${\mu}{\textrm}{m}$ with l/b ratio of 1.43. All isolates from crowns were heterothallic and A1 mating type since oospores were abundantly formed on clarified V-8 juice agar by dual culture with P. capsici A2 mating type. Aplerotic oospores were sized 24-26 ${\mu}{\textrm}{m}$. Antheridia were always amphigynous and recoreded an average of 12$\times$10 ${\mu}{\textrm}{m}$. Hyphal swlling were easily observed, and terminal or intercalary chlamydospores were abundantly formed on V-8 juice agar as well as in C/Z solution and sized av. 28.2 ${\mu}{\textrm}{m}$. This is the first report of Phytophthora rot of strawberry in Korea.

• 한국균학회지
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• 제13권3호
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• pp.179-183
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• 1985

Cylindrocarpon속균(屬菌)이 딸기가 재배(栽培)되는 포장(圃場)의 토양(土壤)에서 토양희석법(土壤稀釋法)으로 분리(分離)되었다. 감자한천배지에서 일주일에 10 mm정도 자라는 균(菌)이며 회백색의 conidial slime을 형성(形成)한다. 균사(菌絲)에서 침상의 phialide의 분생자경(分生子梗)으로 분지(分枝)되고 그위에 소형분생포자(小型分生胞子)와 대형분생포자(大型分生胞子)를 형성(形成)한다. 대형분생포자(大型分生胞子)는 $1{\sim}3$개(個)의 격막(隔膜)을 가지며 크기는 $22{\sim}45{\times}5{\sim}6.5\;{\mu}m$이고 무색원통형(無色圓筒形)으로 양끝은 반원형(半圓形)이다. 후막포자(厚膜胞子)는 water agar상에서 균사(菌絲)의 중간(中間)이나 정단부(頂端部)에서 하나 혹 연쇄상으로 형성(形成)된다. 포자(胞子)나 균사(菌絲)는 서로 쉽게 격합(隔合)된다. 병징(病徵)은 지상부(地上部)에서는 위축(萎縮)되든지 황화(黃化)되며 지하부(地下部)의 뿌리는 썩어 병원성(病原性)이 인정(認定)되었다. 본균(本菌)은 포자(胞子)의 형태(形態), 균사(菌絲)의 생장(生長)과 병원성검정(病原性檢定)을 통(通)하여 Cylindrocarpon destructans Scholten으로 동정(同定)되었다.

• 한국식물병리학회지
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• 제14권6호
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• pp.646-650
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• 1998

Mycological characteristics of Phytophthora nicotianae var. nicotianae SPC10 (A1 type) causing Phytophthora rot of strawberry and the resistances of 11 strawberry cultivars against the pathogen were examined. Optimum temperature for the mycelial growth of the pathogen was obtained in the range of 30~35$^{\circ}C$, and the growth was completely stopped under 13$^{\circ}C$ or over 42$^{\circ}C$. Aerial mycelia were abundant on oatmeal agar (OMA), V-8 juice agar (V8A) and lima bean agar (LBA) medium, although there were slight differences, however, on cornmeal agar (CMA) medium, it was a shape of stellate without aerial mycelia. The colony shape on potato dextrose agar (PDA) medium was rough and irregular whereas the mycelial growth was slow, and some aerial mycelia were only produced in the middle of PDA medium. Optimum temperature for sporangial formation was 3$0^{\circ}C$, and zoospores were mostly released at $25^{\circ}C$ from the sporangia. Sporangia were more produced in C/Z solution with pH 5. 0~6.$0^{\circ}C$ than sterilized distilled water (DSW) and distilled water (DW), and zoospores were also released much more than other solutions. Eleven strawberry cultivars such as Reiko, Hokowase, Eyeberry, Akaneko, Sistakara, Toyonoka, Nyoho, Sulhong, Suhong, Myhong and Wonkyo #3104 revealed the disease incidence up to 88.9~100% by the leaf inoculation with mycelial disk. However, Nyoho and Suhong showed higher level of resistance against the pathogen by root inoculation.

• 한국자원식물학회지
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• 제12권4호
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• pp.260-268
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• 1999

황련(Coptis japonica)의 추출액을 공시하여 Phytophthora capsici, Fusarium oxysporum, Colletotrichum dematium, C. truncatum, Botrytis cinerea, Botryosphaeria dothidea과 Alternaria porri에 대해 항균 활성 검정, 몇가지 작물에 대한 병해 방제 효과를 조사하고 항균 활성 물질을 동정하였다. 황련 추출액은 P. capsici, F. oxysporum, C. dematium, B. cinerea, B. dothidea 및 A. porri에 대해서 항균력이 우수하였다. Methanol을 용매로 추출하여 분리된 물질과 berberine-Cl 표준품의 항균활성을 비교할 때, 황련추출액으로부터 분리된 물질은 표준품 berberine-Cl과 비슷하게 항균력을 나타내었다. 황련 추출액은 고추 역병(83.3%), 참깨 모잘록병 (92.0%) 및 파 검은무늬병(87.5%)에 대해서 방제효과가 인정되었다. 고추 잎과 과실, 파 잎 및 딸기 과실에는 약해가 나타나지 않았으나 고농도에서는 고추 및 참깨의 발아를 억제하거나 유근의 신장을 억제하는 것으로 나타났다. Methanol로 추출한 황련 추출액으로부터 황색 분말 4.24g/100g을 얻을 수 있었다. 이들 물질을 HPLC로 분석한 결과 항균성을 나타내는 물질은 berberine-Cl로 동정되었다.

• 원예과학기술지
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• 제29권3호
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• pp.273-277
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• 2011

딸기의 크라운과 뿌리를 갈변시키는 Fusarium oxysporum f. sp. fragariae에 의한 시들음병은 국내 육묘포장에서 발생하는 중요한 토양병해이다. 육묘기 영양번식을 통한 시들음병 전염 유무를 조사하기 위해 '금향' 품종을 대상으로 시들음병에 감염된 모주로부터 일시채묘 방식으로 자묘를 증식하여 시험에 이용하였다. 시들음병 감염묘와 건전묘간의 자묘생산량 비교에서는 접종 58일 후 감염묘의 러너 발생수는 비닐하우스와 인공광 이용형 육묘 모듈에서 각각 2.7개와 3.8개였으나 건전묘에서는 6.5개와 8.4개로 감염묘에 비해 자묘 생산이 2배 이상 되었다. 시들음병에 감염된 모주에서 영양번식을 통한 자묘의 감염율은 정식 58일 후 1차 러너의 상단부위(2-1)에서 100% 검출되었으나 그 이하 부위에서는 검출이 되지 않았다. 정식 90일 후에는 시들음병균이 1차 러너의 상, 중, 하단 부위(2-1, 2-2, 2-3) 모두에서 100% 검출되었으며, 1차 자묘에서도 60%의 검출율을 보였다. 반면 건전 묘에서는 정식 58일과 90일 후에도 시들음병균은 전혀 검출되지 않았다. 위의 결과를 토대로 딸기 시들음병은 토양 전염 외에 감염된 모주로부터 영양번식을 통한 자묘로의 전염 가능성을 확인하였으며 시들음병의 건전묘 생산방법으로 인공광 환경에서 생산된 1차 자묘를 육묘용 모주로 이용하는 것도 좋을 것으로 판단된다.