• 한국응용곤충학회지
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• 제13권4호
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• pp.245-249
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• 1974

방사선을 이용한 도열병연구의 기초자료로서 도열병균의 포자와 발아균계에 각각 X-ray 10, 40, 80, 120kR를 조사시켜 그들의 방사선감수성 및 생존율을 조사한 결과는 다음과 같다. 1. 도열병균의 포자발아율은 X-ray 소사선량의 증가에 반비례하여 감소되었으며 120kR에서는 거의 생존하지 못하였다. 2. 비교적 저선량인 10kR 조사에서는 초기발아관신장의 촉진 현상을 보였으며 선량의 증가에 따라 균계의 사멸 현상이 현저하였다. 3. X-ray 조사에 의한 발아균계의 생존율 및 신장은 선량의 증가에 반비례하여 감소하였다. 4. X-ray를 조사받은 발아균계는 포자에 비하여 높은 방사선 감수성을 보였으며, 고선량일수록 그 차이는 현저하였다. 5. X-ray 조사에 의한 도열병균의 돌연변이율은 조사선량에 정비례하여 증가하였다.

• The Plant Pathology Journal
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• 제21권4호
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• pp.322-327
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• 2005

Regression models for determining infection periods of apple white rot were developed based on conidial germination and appressorium formation of Botryosphaeria dothidea. A total of 120 apple fruits were inoculated with the fungal conidial suspension and subjected to 6 temperatures and 10 wetness periods. Conidia germinated and produced appressoria, exhibiting swollen tips of germ tubes on the fruit surface. Conidial germination (G) increased with temperature (T) and wetness period (W), and was described as $G=-89.273+7.649T+7.056W-0.109T^{2}-0.085W^{2}-0.066TW(R^{2}=0.75)$. Less than 2 hr of wetness period were enough for conidia to germinate at 25 to $30^{\circ}C$. Effects of temperature and wetness period on appressorium formation (A) could be explained as $A=-1.540-2.375W+0.045W^{2}+0.213TW(R^{2}=0.77)$. The relationship between conidial germination and appressorium formation ($A_g$) was described as$A_g=0.381-0.227G+0.005G^{2}(R^{2}=0.67)$, suggesting that conidial germination may have to reach approximately $43.7\%$ to initiate appressorium formation. Using the regression equation for conidial germination and the criterion of $43.7\%$ conidial germination, an infection model was developed to determine infection periods based on temperature and wetness period. The infection model with the criterion of $43.7\%$ conidial germination was apparently more conservative than the appressorium formation model in determining possibility of apple infection. The infection model seemed sensitive to variable weather conditions, suggesting possible use of the model for timing fungicide sprays to control white rot of apples in practice.

• 한국균학회지
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• 제39권3호
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• pp.256-258
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• 2011

곤충병원성 곰팡이 B. bassiana KK5균의 포자 발아 촉진제를 조사하기 위한 연구가 수행되었다. 탄수화물을 포함한 18 화합물을 B. bassiana 포자와 혼합하여 12시간 동안 water agar에서 배양하였다. 18종의 화합물 중 fructose, mannose 그리고 skim milk와 혼합된 포자의 발아율은 배양 12시간 후 무처리와 비교하여 촉진되는 것으로 조사되었다. 발아 촉진 효과가 확인된 1% fructose, mannose 또는 skim milk와 포자 혼합액을 진딧물에 살포 하였을 때, skim milk와 포자 혼합액의 처리에서 복숭아혹진딧물 3령 약충에 대한 살충증진 효과를 보였다.

• 식물병연구
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• 제17권3호
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• pp.381-385
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• 2011

본 실험에서는 당근 검은잎마름원균의 포자 발아 및 생존에 영향을 끼치는 온도, 상대습도, pH와 건조시간에 대하여 조사하였다. 분생포자의 발아는 $15-25^{\circ}C$ 사이에서 95% 이상의 상대습도 조건에서 촉진되었으나, $5^{\circ}C$에서는 상대습도와 상관없이 발아율이 급격히 감소하였다. 병원균의 분생포자 발아를 촉진하는 최적 환경조건은 습도 95% 이상, 온도 $15-25^{\circ}C$, pH 7.0 및 당근 잎 추출물 0.2%로 확인되었다. 또한 분생포자는 건조시간이 경과함에 따라 발아율이 감소하는 경향을 나타내었다. 그러나 분생포자는 수분 없이 12시간까지 생존 가능하였으며, 수분이 재공급될 경우에는 10% 정도의 발아율을 보였다. 이러한 결과는 A. dauci의 포자 발아 및 발생 생태를 이해하는데 유용한 정보를 제공할 것으로 생각된다.

• 한국산림과학회지
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• 제6권1호
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• pp.19-23
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• 1967

본대학묘포(本大學苗圃)의 리기다소나무 파종상(播種床)에서 입고증상(立枯症狀)의 이병묘(罹病苗)로 부터 분리(分離)한 Alternaria SP.균(菌)의 발육(發育)에 미치는 H-ion농도(濃度)의 영향(影響), 분생포자발아(分生胞子發芽)에 미치는 온도습도(溫度濕度)의 영향(影響) 분생포자형성(分生胞子形成)에 미치는 온도(溫度) 습도(濕度)의 영향(影響)에 대(對)하여 시험(試驗)한바를 요약(要略)하면 다음과 같다.1. 본균(本菌) 발육(發育)에 적당(適當)한 PH의 범위(範圍)는 4.0~9.5로 PH 간(間)의 균발육(菌發育)에 그리 큰 영향(影響)을 나타내지는 않으나 기중(其中) PH 6.5~8.0에서 발육(發育)이 가장 좋았다. 2 발생포자(發生胞子)는 $0^{\circ}C$이하(以下) $40^{\circ}C$이상(以上)의 온도(溫度)에서는 발아(發芽)가 억제(抑制)되고 $5^{\circ}C{\sim}35^{\circ}C$가 발아적온(發芽適溫)이나 기중(其中)에서 $20^{\circ}C$서 발아율(發芽率)이 가장 높았다. 관계온도(關係溫度) 10%이하(以下)에서는 발아(發芽)하지 않았고 85%이상(以上)에서 발아율(發芽率)이 좋았다. 3. 분생포자(分生胞子) $10^{\circ}C$이하(以下) $34^{\circ}C$이상(以上)에서는 형성(形成)되지 않고 온도(溫度) $22^{\circ}C{\sim}28^{\circ}C$ 범위(範圍)에서 관계습도(關係濕度) 85%이상(以上)인 경우(境遇) 형성율(形成率)이 가장 좋았다.

• The Plant Pathology Journal
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• 제15권4호
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• pp.223-227
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• 1999

Pre-penetration behavior of Boytryosphaeria dothidea on apple fruits was investigated with scanning electron microscopy. Once conidia were deposited on the fruit surface, they germainted and produced germ tubes from one or both ends of the conidia. Germ tubes grew over the fruit surface and entered the fruits through lenticels or surface cracks formed naturally. Germ tubes of the fungus also appeared to penetrated the fruits directly with or without forming appressoria. Globose appressoria were frequently formed at the tip of germ tubes on the fruit surface, where no lenticels or surface cracks were found. The conidia collapsed and became flattened to the fruit surface after appressorial formation. Cuticles of fruit surface underneath appressoria and tips of some germ tubes were evidently altered, indicating possibility of direct penetration of the fungus by enzymatic degradation of the cuticle layers. This the first report on the formation of appressoria by B. dothidea.

• Mycobiology
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• 제32권4호
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• pp.186-189
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• 2004

The study on the cultural characteristics of Bipolaris spicifera was conducted to provide with information for the identification, and inoculation studies, etc. B. spicifera grew well at $30{\sim}35^{\circ}C$ and wide range of pH $5.0{\sim}9.0$. However, the fungal growth was retarded at pH 4.0 and 10.0, respectively. Conidia were germinated with 70% at $30^{\circ}C$ but maintained 50% germination even at $40^{\circ}C$, indicating that this pathogen could infect plants at relatively high temperature. The pathogen could not produce conidia under 24 hr fluorescent light condition for 7 days. In contrast, it produced many more conidia at 24 hr dark condition.

• The Plant Pathology Journal
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• 제16권4호
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• pp.206-210
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• 2000

The effect of the electrolyzed oxidizing water on Sphaerotheca fuliginea was investigated with germination and sporulation of the fungal conidia. The sporulation was inhibited by the electrolyzed oxidizing water of pH 2.5, 3.5, and 4.5, but was not inhibited by the distilled water adjusted pH with 1N-HCL solution. However, the electrolyzed oxidizing water did not affect conidial germination. The oxidation-reduction potential at pH 2.5 and pH 3.5 of electrolyzed oxidizing water were 1130 mV and 1060 mV, respectively, but those of distilled water adjusted with HCL solution were 550 mV and 490 mV, respectively. When the electrolyzed oxidizing water of ORP over 1100 mV was sprayed on cucumplanting, the disease severities of powdery mildew were about 8.5% and 19.2%, respectively. Disease severity of a standard control (triflumizole 30% WP, $500\textrm{mg}\textrm{/L}$) was about 3.0%, while that of plants without electrolyzed oxidizing water was to 45.8%.

• 한국응용곤충학회지
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• 제24권3호
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• pp.135-139
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• 1985

Influence of temperature, relative humidity, spore washing and spore drying on conidial germination of Alternaria porri(Ell.) Cif. was studied. Maximum conidial germination occurred at 100% relative humidity prevailing for 6 hours or more at $25^{\circ}C$. Conidial germination decreased with increase in number of spore washings. Drying of conidia for more than half an hour caused significant decrease in germination. In all the experiments, conidial germinatio increased with increase in incubation period.

• 한국응용곤충학회지
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• 제24권3호
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• pp.129-133
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• 1985

Effect of some physical and chemical factors on germination of conidia of Alternaria alternata (Fries) Keissler causing fruit rot of apple was investigated. The germination was maximum at $30^{\circ}C$, 100 per cent RH and at 5.5 pH Syllit, amongst the 11 fungicides and Planofix, amongst the 5 growth regulators caused maximum inhibition of conidial germination.