• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.120-124
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• 1998

The conidial germination of Pestaotiopsis theae was occurred in cells attched with pedicels, the inferior cell of conidium. The cells were swollen like a ball, and then germinated in 4 hours under favorable conditions. Generally, it was considered that fifty percent of whole conidia was germinated in the range 6~12 hours. The optimum temperature and pH for conidial germination of P. theae (SP-3) causing leaf blight on sweet persimmon was $25^{\circ}C$ and pH 5, respectively. Conidial germination rate was higher than 90% at 100% relative humidity, but never germinated at a relative humidity lower than 88.5%. Conidial germination was highest at the concentration of 1~4$\times$104 conidia/ml. In case of cultural media, the conidial germination was higher than 90% on PDA, PSA, OME and Leonian agar. There was no relationship between light and conidial germination. It was concluded that the key environmental factors affecting conidial germination of the fungus (SP-3) were temperature and moisture.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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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.

• The Plant Pathology Journal
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• v.21 no.4
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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.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.61-67
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• 1984

Conidial germination of Septoria glycines Hemmi, brown spot fungus of soybean, was studied by slide germination test. Poor conidial germination of S. glycines was observed on sterile distilled water, but potato dextrose agar(PDA) and distilled water floated with soybean leaf disc furnished a satisfactory medium for conidial germination. Exogenous supply of carbon source was essential for conidial germination, while phosphorous and potassium were not evident as that for carbon. Soluble starch was the most suitable as a carbon source for conidial germination and followed by D-glucose, D-galactose and lactose in that order. Maximum germination was attained in the $5\times10^{-2}mol$. concentration of glucose. Germination was decreased with increment of conidial concentration and was almost completely suppressed in the density of 10,000 conidia per $mm^2$. It suggested existing a self-inhibitor(s). Non-washed conidia germinated more than washed conidia and this was obvious when the conidia density was over $2\times10^3$ conidia per $mm^2$ on the dry agar block.

• Mycobiology
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• v.32 no.1
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• pp.42-46
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• 2004

Five fungicides such as rovral, bavistin, cupravit, dithane M-45 and thiovit were tested against conidial germination of Fusarium oxysporum. Dithane M-45 was the most effective against the fungus. Rests of the fungicides were more or less effective in the inhibition of conidial germination after $5{\sim}30$ minutes immersion in $500{\sim}2500$ ppm concentration. Five plant extracts(leaf extracts of Ocimum sanctum, Lantana camera, Calotropis procera, Azadirachta indica and Vinca rosea) found to be more or less effective against the fungus. 'Dhup' somke have good inhibitory effect on conidial germination of F. oxysporum.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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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.

• Research in Plant Disease
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• v.17 no.3
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• pp.381-385
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• 2011

Effects of temperatures, relative humidity, pH, and dry periods on conidial germination of Alternaria dauci were evaluated under in vitro conditions. Conidial germination was accelerated at over 95% relative humidity in $15^{\circ}C$ to $25^{\circ}C$ condition. Conidial germination was rapidly reduced at 5 regardless of relative humidity conditions. More than 50% of the conidial germination were initiated within 2 h at $25^{\circ}C$ through pH 5 to 7. The highest conidial germination of A. dauci was on 0.2% of carrot leaf extract. Conidia could survive longer than 12 h, even though its germination decreased. After a 12 h dry period, around 10% of conidia revived and germinated when conidia were hydrated again. These results could be used as the useful information on conidial germination of A. dauci and ecology of Alternaria leaf blight.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.41-46
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• 1986

Exogenous factor and nutrients affecting for conidial germination of Colletetrichum dematium f. sp. capsicum causing red pepper anthracnose were studied by slide germination test. Optimum temperature of conidial germination was at $28^{\circ}C$, ranging 15 to $35^{\circ}C$. Optimum pH was at 5.5, ranging 4.5 to 8.0, and more than 90% of relative humidity (RH) was optimum. Poor conidial germination of the fungus was observed on sterile distilled water, but potato sucrose broth (PSB), red pepper fruit broth (RPFB), green pepper fruit broth (GPFB) and pepper leaf broth (PLB) furnished a satisfactory nutrients for conidial germination. Exogenous supply of carbon and nitrogen sources were essential for conidial germination, while potassium, phosphorous and sulfur were not evident as that for carbon and nitrogen. Soluble starch was the most suitable as a carbon source for conidial germination and followed by D-glucose, D-galactose and lactose in that order. Maximum germination was attained in the $1{\times}10^4$ conidia per ml. Germination was decreased with increment of conidial concentration, and in the density of $5{\times}10^4$ conida per ml, germination was nearly supipressed. It suggested existing a self-inhibitor. Non-washed conidia germinated more than washed conidia, and conidial germination was also gradually decreased by increasing conidial density.

• Mycobiology
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• v.33 no.4
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• pp.200-205
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• 2005

In Northern Bangladesh, generally mango trees are planted as agroforest that gives higher Net Present Value (NPV) than traditional agriculture. Mango anthracnose caused by Colletotrichum gloeosporioides Penz. is seen as a very destructive and widely distributed disease, which results in poor market value. Five fungicides such as Cupravit, Bavistin, Dithane M-45, Thiovit and Redomil were tested against conidial germination of C. gloeosporioides. Dithane M-45 and Redomil were the most effective when the conidia were immersed for $10{\sim}20$ minutes at $500{\sim}1000\;ppm$ concentrations. Antifungal activities of 13 plant extracts were tested against conidial germination of C. gloeosporioides. Conidial germination of C. gloeosporioides was completely inhibited in Curcuma longa (leaf and rhizome), Tagetes erecta (leat) and Zingiber officinales (rhizome) after 15 minutes of incubation respectively.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.325-332
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• 1994

In order to find out formulation and effect of soil amendment on Fusarium wilt of sesame caused by Fusarium oxysporum f. sp. vasinfectum, the study was conducted during the last two years of 1992 to 1993. Among 14 chemicals (1%, w/w) added to soil including CaO individually, Al2(SO4)3, Alum, and CaO suppressed mycelial growth and conidial germination of F.oxysporum f. sp. vasinfectum. CaCl2 suppressed mycelial growth only, while glycerine, KCl, K2 HPO4, and triple superphosphate suppressed conidial germination. Suppression rate was ranged from 21 to 100% on mycelial growth. The 8 chemicals were finally selected. Among the 4 organic compounds, composted pine bark showed definite suppression on mycelial growth and conidial germination of the fungus, whereas milled alfalfa leaves was only effective on conidial germination of Fusarium wilt pathogen. The antagonist Trichoderma harzianum grew well in the soil medium amended with the composted pine bark and chemicals mixture (CPM) amendment (1%, w/w) and suppressed mycelial growth of the fungus effectively. In pot test, Fusarium wilt of sesame was completely controlled by CPM amendment.