Effect of the triazine herbicides Goltix and Igran on germination and growth of Aspergillus fumigatus, Fusarium oxysporum, Helminthosporium oryzae, and Verticillium agaricinum

1989 ◽  
Vol 67 (3) ◽  
pp. 737-741 ◽  
Author(s):  
E. E. A. Elwy ◽  
M. Osman ◽  
T. M. A. Abdel Rahman ◽  
I. M. K. Ismail
Keyword(s):  
Spore Germination ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Germ Tube ◽  
Fungal Species ◽  
Tube Length ◽  
Liquid Cultures ◽  
Germ Tube Length ◽  
Helminthosporium Oryzae ◽  
Germination And Growth

The effect of two triazines on spore germination, radial growth, and biomass production were studied in A. fumigatus, F. oxysporum, H. oryzae, and V. agaricinum. Igran inhibited spore germination of all species to some extent and at 1000 ppm completely inhibited spore germination in A. fumigatus and F. oxysporum. Goltix inhibited germination of F. oxysporum and H. oryzae, but stimulated germination of A. fumigatus and V. agaricinum. Germ tube length was significantly decreased at high herbicide concentrations. Both derivatives reduced radial growth rate as well as mycelial growth in liquid cultures. The level of inhibition depends on the herbicide, its concentration, and the fungal species.

scholarly journals Effect of Legume Extracts on Germination, Seedling Health of Beans (Phaseolus vulgaris L.) and Soil Microorganisms

2019 ◽  
pp. 1-13
Author(s):  
Oliver Otieno Okumu ◽  
James Wanjohi Muthomi ◽  
John Ojiem ◽  
Rama Narla ◽  
John Huria Nderitu
Keyword(s):  
Seed Germination ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Germ Tube ◽  
Tube Length ◽  
Green Manures ◽  
Seedling Length ◽  
Germ Tube Length ◽  
Ethanol Extracts ◽  
Germ Tube Elongation

Application of undecomposed green manure has been reported to cause poor emergence and establishment of common beans in the field. Therefore, to understand the mechanisms’ contributing to the poor crop establishment, the effect of extracts from fresh and decomposed legume green manures on bean seed germination, fungal mycelial growth, spore germination and germ tube elongation were evaluated. The extracts were prepared in either ethanol or distilled water. Data was collected on percentage seed germination, seedling length, mycelial radial growth, spore germination and germ tube elongation. Ethanol extracts from fresh lablab inhibited bean germination by 56%, increased mean germination time to 8 days, and decreased germination index while ethanol extracts of groundnut and beans caused highest inhibition in bean shoot length and reduced biomass. Ethanol extracts from fresh green manures significantly inhibited fungal mycelial growth while the aqueous extracts from beans, groundnuts and soybean had significant level of antifungal activity while aqueous lablab extracts stimulated mycelial. Aqueous extract of lablab and soybean enhanced spore germination by over 70% with more pronounced effect on germ tube length and number of germ tubes by 8.0% and 13% respectively. The study comparatively reveals that the extract of lablab was inhibitory to common bean germination compared to other legume extracts and also stimulated the growth of root rot pathogens that may have resulted in poor establishment of beans.

scholarly journals In vitro effect of substrate, temperature and photoperiod on Phakopsora pachyrhizi urediniospore germination and germ tube growth

2015 ◽  
Vol 41 (2) ◽  
pp. 101-106
Author(s):  
Marta Maria Casa Blum ◽  
Erlei Melo Reis ◽  
Francieli Tavares Vieira ◽  
Rita Carlini
Keyword(s):  
Substrate Temperature ◽  
Spore Germination ◽  
Leaf Extract ◽  
Germ Tube ◽  
Tube Growth ◽  
Tube Length ◽  
Germ Tube Length ◽  
Soybean Leaf ◽  
Germ Tube Growth

In vitro experiments were conducted to assess the effects of substrate, temperature and time of exposure to temperature and photoperiod on P. pachyrhizi uredospore germination and germ tube growth. The following substrates were tested: water-agar and soybean leaf extract-agar at different leaf concentrations (0.5, 1.0, 2.0 and 4.0 g of leaves and 15g agar/L water), temperatures (10, 15, 20, 25, 30, and 35oC) and times of exposure (1, 2, 3, 4, 5, 6, 7, and 8 hours) to temperature and 12 different photoperiods. The highest germination and germ tube length was found for the soybean leaf extract agar. Maximum P. pachyrhizi uredospore germination was obtained at 21.8 and 22.3°C, and maximum germ tube growth at 21.4 and 22.1°C. The maximum uredospore germination was found at 6.4 hours exposure, while the maximum germ tube length was obtained at 7.7 h exposure. Regarding photoperiod, the maximum spore germination and the maximum uredospore germ tube length were found in the dark. Neither spore germination nor uredospore germ tube growth was completely inhibited by the exposure to continuous light.

scholarly journals The Effect of Resin and Monoterpenes on Spore Germination and Growth in Fusarium circinatum

2015 ◽  
Vol 105 (1) ◽  
pp. 119-125 ◽  
Author(s):  
S. L. Slinski ◽  
F. Zakharov ◽  
T. R. Gordon
Keyword(s):  
Pinus Radiata ◽  
Spore Germination ◽  
Direct Contact ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Dry Weight ◽  
Pitch Canker ◽  
Fusarium Circinatum ◽  
Saturated Atmosphere ◽  
Germination And Growth

Resin obtained from Pinus radiata and five monoterpene components of resin (limonene, α-pinene, β-pinene, camphene, and myrcene) were tested to determine their effects on mycelial growth and germination and survival of spores of Fusarium circinatum, the cause of pitch canker in pine, and F. temperatum, which is interfertile with F. circinatum but not pathogenic to pine. Averaged across all treatments, F. temperatum sustained the greatest reduction in radial growth (16.9 ± 0.02% of control). The greatest reduction in dry weight also occurred in F. temperatum (11.7 ± 0.01% of control), and all isolates of F. circinatum were significantly less affected (P < 0.05). Spore germination rates in a saturated atmosphere of monoterpenes were relatively high for all tested isolates but, when placed in direct contact with resin, spore survival was significantly greater for F. circinatum than for F. temperatum. Our results are consistent with the hypothesis that greater tolerance of resin is one factor distinguishing F. circinatum from the nonpathogenic F. temperatum. However, differential tolerance of monoterpene components of resin is not sufficient to explain the observed variation in virulence to pine in F. circinatum.

Interaction of Xanthomonas campestris pv. undulosa or Pseudomonas cepacia with Septoria nodorum in vitro and in vivo

1982 ◽  
Vol 28 (2) ◽  
pp. 205-210 ◽  
Author(s):  
J. B. Jones ◽  
C. W. Roane
Keyword(s):  
Spore Germination ◽  
Xanthomonas Campestris ◽  
Leaf Extract ◽  
Germ Tube ◽  
Tube Length ◽  
Pseudomonas Cepacia ◽  
Septoria Nodorum ◽  
Germ Tube Length ◽  
Wheat Leaf

Xanthomonas campestris pv. undulosa did not inhibit growth or spore germination of Septoria nodorum on wheat leaf extract agar, whereas Pseudomonas cepacia produced a zone of complete inhibition of spore germination up to 17.5 mm and reduced germination up to 5 cm from the bacterial front. Culture filtrates of the two bacteria grown in 'Blueboy' or 'Arthur' wheat leaf extract broth were incorporated into fresh wheat leaf extract broth. These filtrates caused a reduction in growth (dry weight) of S. nodorum compared with growth in unamended extract. Fungal mass was considerably lower in P. cepacia filtrate of 'Arthur' wheat than in the X. campestris pv. undulosa filtrate or the control. The extent of reduction by P. cepacia filtrate suggests an antibiotic effect. In phosphate buffer, X. campestris pv. undulosa reduced spore germination and germ tube length of S. nodorum, while P. cepacia inhibited germination and germ tube growth completely. In vivo, X. campestris pv. undulosa had no effect on spore germination but did reduce germ tube length whereas P. cepacia inhibited both parameters.

scholarly journals Antifungal Efficacy of Plant Oils Containing Thymol and Carvacrol in Controlling Botrytis cinerea, the Causal Agent of Grape (Vitis vinifera) GrayMould

2018 ◽  
Vol 16 (02) ◽  
pp. 15-24
Author(s):  
Zaker M ◽  
Zaker L
Keyword(s):  
Essential Oils ◽  
Botrytis Cinerea ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Germ Tube ◽  
Plant Diseases ◽  
Plant Oils ◽  
Horticultural Products ◽  
Antifungal Efficacy ◽  
Germ Tube Elongation

The efficacy of a large number of plant extracts and essential oils in controlling plant diseases has been proven worldwide. Botrytis cinerea has attacked a wide host range causing severe loss in the field and at storage. In this study the antifungal efficacy of essential oils of three medicinal plants namely wild marjoram (Zataria multifolia), wild savory (perennial) (Satureja mutica) and savory (annual) (Satureja hortensis) possessing these compounds at three concentrations: 50, 100 and 200 ppm were evaluated in controlling the mycelial growth, spore germination and germ tube elongation of B. cinerea. All treatments except savory (annual) essential oil at 50 ppm showed significant differences with the control in inhibiting the mycelial growth as well as spore germination and germ tube elongation of B. cinerea (p=0.01). It was also noted that wild marjoram at 100 ppm and wild savory (perennial) essential oils at 200 ppm could completely (100%) inhibit the growth of the fungus. Essential oils from wild marjoram and wild savory had higher antifungal activity than annual savory. Their suitable formulations could be prepared and used as safe alternatives for controlling moulds of horticultural products during storage. The Agriculturists 2018; 16(2) 15-24

scholarly journals Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum

2010 ◽  
Vol 40 (No. 4) ◽  
pp. 128-134 ◽  
Author(s):  
H. Bryk ◽  
B. Dyki ◽  
P. Sobiczewski
Keyword(s):  
Botrytis Cinerea ◽  
Spore Germination ◽  
Germ Tube ◽  
Inhibitory Effect ◽  
Penicillium Expansum ◽  
Bacterial Strains ◽  
Liquid Cultures ◽  
Pseudomonas Spp ◽  
Apple Leaves ◽  
Germ Tube Elongation

The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48&ndash;76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present &ndash; the hyphal tips were swollen and ball-shaped spore-like structures aggregated in chains were formed.

scholarly journals Influence of Iron on Cylindrocarpon Root Rot Development on Ginseng

2006 ◽  
Vol 96 (11) ◽  
pp. 1179-1187 ◽  
Author(s):  
Mahfuzur Rahman ◽  
Zamir K. Punja
Keyword(s):  
Enzyme Activity ◽  
Phenolic Compounds ◽  
Root Rot ◽  
High Performance ◽  
Germ Tube ◽  
Dry Weight ◽  
Colony Growth ◽  
Tube Length ◽  
Germ Tube Length

Cylindrocarpon root rot, caused by Cylindrocarpon destructans, is an important disease on ginseng (Panax quinquefolius) in Canada. We studied the effects of iron (Fe) on disease severity and pathogen growth. When Hoagland's solution was amended with Fe at 56 and 112 μg/ml compared with 0 μg/ml, disease initiation and final severity on hydroponically maintained ginseng roots was significantly (P<0.0001) enhanced. Under field conditions, wounding of roots with a fine needle followed by application of 0.05% FeNaEDTA to the rhizosphere of treated plants significantly enhanced Cylindrocarpon root rot in 2003 and 2004 compared with unwounded roots with Fe or wounded roots without Fe. Foliar applications of Fe (as FeNaEDTA) to ginseng plants three times during the 2002 and 2003 growing seasons significantly increased Fe levels in root tissues. These roots developed larger lesions following inoculation with C. destructans in vitro. When radioactive Fe (59Fe) was applied to the foliage of ginseng plants, it was detected in the secondary phloem and in cortical and epidermal tissues within 1 week. Artificially wounded areas on the roots accumulated more 59Fe than healthy areas. Diseased tissue also had threefold higher levels of phenolic compounds and Fe compared with adjoining healthy tissues. High-performance liquid chromatography analysis revealed enhanced levels of protocatechuic acid, chlorogenic acid, caffeic acid, ferulic acid, cinnamic acid, phloridizin, and quercetin. Phenolic compounds produced in diseased and wounded tissues sequestered Fe in vitro. The effects of Fe on mycelial growth, conidial germ tube length, and secondary branching of germ tubes of C. destructans were examined in vitro. When grown on Chrome-azurol S medium, Fe also was sequestered by C. destructans through siderophore production, which was visualized as a clearing pigmented zone at the margin of colonies. Mycelial dry weight was significantly increased in glucose/ yeast broth containing Fe at 56 or 112 μg/ml. Conidial germ tube length and secondary branching of hyphae also were enhanced after 8 and 16 h by Fe. Colony growth of C. destructans was not enhanced by Fe, but significantly greater spore production was observed with Fe at 56 and 112 μg/ml compared with no Fe in the medium. Although these levels of Fe had no effect on fungal pectinase enzyme activity, polyphenoloxidase (PPO) activity was significantly (P <0.0001) enhanced. We conclude that Fe enhances Cylindrocarpon root rot through enhanced pathogen growth, sporulation, and PPO enzyme activity. Fe sequestered by phenolic compounds produced in wounded tissues can enhance Fe levels at the site of infection. The pathogen also has the ability to sequester Fe at these sites.

scholarly journals 488 Effect of Oat Extract on Pea Root Rot Pathogen Aphanomyces euteiches

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 529B-529
Author(s):  
M.A. Chandler ◽  
V.A. Fritz ◽  
F.L. Pfleger ◽  
R.R. Allmaras
Keyword(s):  
Spore Germination ◽  
Root Rot ◽  
Mycelial Growth ◽  
Great Lakes Region ◽  
Aphanomyces Euteiches ◽  
Causal Organism ◽  
Economic Threat ◽  
Pea Root ◽  
Germination And Growth ◽  
Pea Root Rot

Pea root rot is a serious economic threat to pea production in the Great Lakes region. The primary causal organism is Aphanomyces euteiches Drechs., which is responsible for an estimated 10% annual crop loss. A fall oat (Avena sativa) rotation before spring pea planting reduces disease severity. To better understand the beneficial effect of oat on A. euteiches, isolated individual pathogen lifecycle stages of zoospores, mycelium, and oospores were treated in culture with oat extract. Resulting mycelial mats were dried and weighed. Treatment with 90%, 70%, 50%, and 30% oat extract resulted in significant spore germination and mycelial growth of A. euteiches. In the presence of nutrient solution, oat extract concentrations of 90%, 70%, 50%, and 30% significantly enhanced spore germination and mycelial growth of the pathogen. These results demonstrate that the use of oat extract results in dosage dependent germination and growth of A. euteiches.

ENZYME ACTIVITIES DURING THE ASEXUAL CYCLE OF NEUROSPORA CRASSA: I. SUCCINIC DEHYDROGENASE

1967 ◽  
Vol 13 (9) ◽  
pp. 1203-1210 ◽  
Author(s):  
G. J. Stine
Keyword(s):  
Neurospora Crassa ◽  
Enzyme Activities ◽  
Soluble Protein ◽  
Mycelial Growth ◽  
Germ Tube ◽  
Succinic Dehydrogenase ◽  
Growth Yield ◽  
Conidial Germination ◽  
Germination And Growth ◽  
Asexual Cycle

Separate extracts of Neuorospora crassa grown either in Vogel's medium N, medium N + glutamate, or medium N which had been made deficient in zinc, were assayed for succinic dehydrogenase and soluble protein at intervals throughout the asexual cycle. Succinic dehydrogenase, although apparently unnecessary for either the formation of conidia or conidial germination, does appear to be necessary for mycelial growth and for the production of conidiophores. Differences in the amount of enzyme during morphologically distinct states of differentiation (i.e. production of the germ tube and production of the conidiophore) may serve as an indicator of significant changes in the physiology of Neurospora at these times during development.The level of succinic dehydrogenase in the conidiophore before its differentiation into conidia appears to influence the amount of this enzyme found in the conidia. This is in keeping with the idea that conditions prevailing in the cytoplasm before the formation of conidia may directly influence the constituents subsequently found in the conidia which determine conidial viability, rate of germination, and growth yield.

Soil fungistasis: fungus spore germination in soil at spore densities corresponding to natural population levels

1974 ◽  
Vol 20 (5) ◽  
pp. 751-754 ◽  
Author(s):  
Gary J. Griffin ◽  
Robert H. Ford
Keyword(s):  
Natural Population ◽  
Spore Germination ◽  
Tube Length ◽  
Test Fungus ◽  
Germ Tube Length ◽  
Fungus Spore ◽  
Soil Fungistasis ◽  
Time Observation ◽  
First Time ◽  
Spore Densities

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.

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