scholarly journals Extraction of chelerythrine and its effects on pathogenic fungus spore germination

2017 ◽  
Vol 13 (52) ◽  
pp. 600 ◽  
Author(s):  
Min Zhao ◽  
Qinghui Wei ◽  
Xiaoyan Li
1971 ◽  
Vol 47 (5) ◽  
pp. 729-730 ◽  
Author(s):  
L. Calpouzos ◽  
Ho-Shii Chang

1974 ◽  
Vol 20 (5) ◽  
pp. 751-754 ◽  
Author(s):  
Gary J. Griffin ◽  
Robert H. Ford

An autoradiographic spore-location technique is described that allows for the first time observation of spore germination in soil at low natural population levels (103 to 104 spores/g soil). When Fusarium solani f. sp. phaseoli was used as a test fungus, percentage macroconidial germination was greatest in nonsterile soil at 3 × 103 and 3 × 104 conidia/g soil, and percentage germination decreased sharply with increasing conidial density. Mean germ tube length was greater at 3 × 103 than at 3 × 104 conidia/g soil. The results indicate that inhibition of spore germination (apparent soil fungistasis) of a fungus in soil environments at conventionally used high spore densities (105 to 106 spores/g soil) may not mean that spores of the fungus will be equally inhibited in the same environments at lower natural population levels.


2017 ◽  
Vol 70 ◽  
pp. 112-119 ◽  
Author(s):  
P.N. Wood ◽  
B.M. Fisher

Phlyctema vagabunda (syn: Neofabraea alba) is a plant pathogenic fungus that causes bull’s eye rot on apples and pears. Phlyctema vagabunda fruit infections occur in orchards predominantly pre-harvest, and eventually express as a fruit rot after 4—5 months of cool storage. Twelve fungicides (captan, carbendazim, copper hydroxide, cyprodinil, difenoconazole, dithianon, dodine, isopyrazam, metiram, lime sulphur, sulphur and trifloxystrobin) were tested in vitro for their effects on spore germination and mycelial growth of P. vagabunda. Spore germination was inhibited by metiram, captan, dodine, dithianon, lime sulphur, carbendazim and isopyrazam, in order of effectiveness. Carbendazim, isopyrazam, difenoconazole and cyprodinil, in order of effectiveness, inhibited mycelial growth when used at label rates. Wettable sulphur was ineffective in both assays. On detached apple fruit, carbendazim, cyprodinil, trifloxystrobin and isopyrazam (in order of effectiveness) inhibited lesion development.


1989 ◽  
Vol 67 (1) ◽  
pp. 18-23 ◽  
Author(s):  
G. W. T. Wilson ◽  
B. A. Daniels Hetrick ◽  
D. Gerschefske Kitt

When the effect of nonsterile soil on vesicular–arbuscular mycorrhizal fungus spore germination was examined, significantly fewer Glomus etunicatum (22 vs. 63 and 64%) or Glomus mosseae (23 vs. 80 and 79%) spores germinated in nonsterile soil than in autoclaved or pasteurized soil, respectively. In some cases, addition of nonsterile soil sievings to autoclaved or pasteurized soil also reduced germination, as compared with germination in unamended pasteurized or autoclaved soil. Germination was reduced by as much as 45% in autoclaved or pasteurized soil if spores were surface sterilized. However, surface sterilization of G. etunicatum spores did not affect dry weight of inoculated big bluestem plants, but mycorrhizal root colonization was reduced when spore-associated microbes were removed from spores by surface sterilization. The detrimental effect of soil microbes on spore germination and mycorrhizal growth response may reflect microbial competition for nutrients since germination of G. etunicatum and G. mosseae was reduced when pasteurized soil was amended with 15, 30, or 60 ppm phosphorus and 60 ppm phosphorus, respectively. An optimum range of available phosphorus may exist, above or below which germination is suppressed.


1993 ◽  
Vol 39 (2) ◽  
pp. 234-244 ◽  
Author(s):  
Hamid Amir ◽  
Nourredine Mahdi

Thirteen strains of Fusarium solani and F. oxysporum were isolated from an initial lot of 96 and submitted to 11 different tests to determine their ecological aptitudes. Results showed a great diversity with respect to performance. Significant total correlations with the strain aptitudes to protect flax against vascular fusariosis in one soil (efficacy) were obtained for three characters: quantity of microconidia produced (negative correlation), respiratory activity, and antagonistic effect in soil in the presence of a pathogenic fungus (positive correlations). Other properties were studied, such as mycelial growth, production of macroconidia, production of chlamydospores, spore germination aptitude, inhibiting effect of secretions against F. oxysporum f.sp. lini, saprophytic development in disinfected soil, and aptitude to maintain their development and activity in soil; all these properties showed generally high partial correlations with respect to efficacy. The multiple correlations obtained for different aptitude associations tested were clearly more significant than simple correlations. The results suggest that competition among Fusarium spp., here illustrated by efficacy, can be interpreted as a complex power corresponding to the sum of different particular aptitudes, notably: global activity, mycelial growth, sporulation, spore germination capacity, and secretion of compounds inhibiting competing germs. If selection of antagonistic Fusarium strains for biological control were based upon a single criterion, this would be arbitrary in part; a multiple-step selection would be recommended. The present work was performed on a single soil and with a limited number of strains; consequently, further experiments are required.Key words: Fusarium, competition, fusariosis, biological control.[Journal translation]not available


Author(s):  
Robert W. Roberson

The use of cryo-techniques for the preparation of biological specimens in electron microscopy has led to superior preservation of ultrastructural detail. Although these techniques have obvious advantages, a critical limitation is that only 10-40 μm thick cells and tissue layers can be frozen without the formation of distorting ice crystals. However, thicker samples (600 μm) may be frozen well by rapid freezing under high-pressure (2,100 bar). To date, most work using cryo-techniques on fungi have been confined to examining small, thin-walled structures. High-pressure freezing and freeze substitution are used here to analysis pre-germination stages of specialized, sexual spores (teliospores) of the plant pathogenic fungus Gymnosporangium clavipes C & P.Dormant teliospores were incubated in drops of water at room temperature (25°C) to break dormancy and stimulate germination. Spores were collected at approximately 30 min intervals after hydration so that early cytological changes associated with spore germination could be monitored. Prior to high-pressure freezing, the samples were incubated for 5-10 min in a 20% dextran solution for added cryoprotection during freezing. Forty to 50 spores were placed in specimen cups and holders and immediately frozen at high pressure using the Balzers HPM 010 apparatus.


Planta Medica ◽  
2012 ◽  
Vol 78 (11) ◽  
Author(s):  
M Kumarihamy ◽  
S Khan ◽  
D Ferreira ◽  
E Croom Jr ◽  
S Duke ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document