Liaisons entre les aptitudes écologiques de différentes souches de Fusarium et leur efficacité dans la protection de plants de lin contre la fusariose vasculaire

1993 ◽  
Vol 39 (2) ◽  
pp. 234-244 ◽  
Author(s):  
Hamid Amir ◽  
Nourredine Mahdi
Keyword(s):  
Biological Control ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Pathogenic Fungus ◽  
Antagonistic Effect ◽  
Partial Correlations ◽  
Growth Production ◽  
Positive Correlations ◽  
Step Selection ◽  
Global Activity

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

scholarly journals The effect of fungicides on spore germination, mycelial growth and lesion development of Phlyctema vagabunda (syn: Neofabraea alba) (bull’s eye rot of apples)

2017 ◽  
Vol 70 ◽  
pp. 112-119 ◽  
Author(s):  
P.N. Wood ◽  
B.M. Fisher
Keyword(s):  
Spore Germination ◽  
Mycelial Growth ◽  
Pathogenic Fungus ◽  
Apple Fruit ◽  
Fruit Rot ◽  
Copper Hydroxide ◽  
Lesion Development ◽  
Lime Sulphur ◽  
Bull's Eye

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.

Microorganisms Associated with Eutypellaparasitica in Acersaccharum and A. rubrum

1974 ◽  
Vol 4 (2) ◽  
pp. 207-212 ◽  
Author(s):  
J. T. Kliejunas ◽  
J. E. Kuntz
Keyword(s):  
Spore Germination ◽  
Mycelial Growth ◽  
Sugar Maple ◽  
Antagonistic Effect ◽  
Red Maple ◽  
Outer Bark ◽  
Culture Filtrates

Many species of microorganisms were associated with Eutypellaparasitica in cankers on maple. The same species of microorganisms were present in noninoculated artificial branch and trunk wounds on maple trees and in natural wounds on sugar maple and red maple seedlings. There was little antagonistic effect of the associated microorganisms on growth of E. parasitica when paired in culture. Filtrates containing extracts of sugar maple outer bark saprophytes had no effect on spore germination or mycelial growth of E. parasitica. Isolations from branch stubs associated with natural cankers and from tissues in the trunk indicated that E. parasitica invaded tissues colonized first by other microorganisms.

scholarly journals Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
M. M. Rahman ◽  
M. E. Ali ◽  
A. A. Khan ◽  
A. M. Akanda ◽  
Md. Kamal Uddin ◽  
...  
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Erwinia Carotovora ◽  
Soft Rot ◽  
Control Agent ◽  
Antagonistic Activity ◽  
Antagonistic Effect ◽  
Antagonistic Bacteria ◽  
And Storage

A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacteriumErwinia carotovorasubsp.carotovora(Ecc) were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was testedin vitroagainst the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited thein vitrogrowth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genusBacillusand the isolate E-45 asLactobacillussp. The stronger antagonistic activity against Ecc P-138 was found in E-65in vitroscreening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5%) antagonistic effect of E-65 was observed in the Granola and the lowest (32.7%) of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

scholarly journals Growth and sporulation of Metarhizium flavoviride var. Flavoviride on culture media and lighting regimes

2001 ◽  
Vol 58 (3) ◽  
pp. 613-616 ◽  
Author(s):  
Sideney Becker Onofre ◽  
Cindia Mara Miniuk ◽  
Neiva Monteiro de Barros ◽  
João Lúcio Azevedo
Keyword(s):  
Biological Control ◽  
Mycelial Growth ◽  
Culture Media ◽  
Agar Medium ◽  
Potato Dextrose Agar ◽  
Continuous Illumination ◽  
Agricultural Pests ◽  
Dark Cycle ◽  
Metarhizium Flavoviride ◽  
Conidia Production

Entomopathogenic fungi from the genus Metarhizium are largely used for the biological control of agricultural pests by conidia spreading on the field. Although conidia production is well studied in M. anisopliae, only few research studies were done in M. flavoviride. The present work was carried out alming to evaluate the Mycelial growth and sporulation of the entomopathogenic fungus Metarhizium flavoviride var. flavoviride growing at 27 ± 2°C on Potato-dextrose-agar (PDA), Czapek-agar (CZP) and a complete agar medium (CM) under three lighting regimes, (continuous illumination, light/dark cycle and an black light/dark cycle) were investigated. A completely randomized 3 × 3 (culture media × lighting regime) factorial design with four replicates was used. The best mycelial growth and sporulation occurred on the PDA and CM media under continuous illumination (P <= 0,05).

scholarly journals Compatibility of fungal bioagent for bacterial leaf blight of rice with chemical pesticides, commonly used in rice cultivation

2013 ◽  
Vol 5 (2) ◽  
pp. 378-381 ◽  
Author(s):  
Gokil Prasad Gangwar
Keyword(s):  
Adverse Effect ◽  
Biological Control ◽  
Chemical Control ◽  
Mycelial Growth ◽  
Crop Protection ◽  
Leaf Blight ◽  
Rice Cultivation ◽  
Bacterial Leaf Blight ◽  
Copper Oxychloride ◽  
Chemical Pesticides

Though the pesticides have adverse effects but they still are very important in crop protection. Hence, present study on compatibility of fungal bioagent (Trichoderma harzianum) of bacterial leaf blight of rice with chemical pesticides which are commonly used in rice cultivation was carried out with aim to look the possibilities of integrating biological control with chemical control to manage bacterial leaf blight of rice effectively. All the chemical pesticides (fungicides, antibiotic, insecticides and herbicides) exhibited varying adverse effect on mycelial growth of T. harzianum but none of these was antisporulant. Among fungicides and antibiotic, copper oxychloride and streptocycline was compatible with T. harzianum at all concentrations (2000, 1000, 500 and 250 ppm) but mancozeb exhibited compatibility only on lower concentrations (500 and 250 ppm). All insecticides and herbicides were compatible with T. harzianum at all concentrations (2000, 1000, 500 and 250 ppm). Further studies are required in this area of research.

Screening of Existing and New Boxwood Cultivars for Disease Resistance and In Vitro Fungicide Screening to Manage Boxwood Dieback Caused by Colletotrichum theobromicola

2021 ◽  
Author(s):  
Harleen Kaur ◽  
Monique DeSouza ◽  
Raghuwinder "Raj" Singh
Keyword(s):  
Active Ingredient ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Management Practices ◽  
Management Strategies ◽  
Host Susceptibility ◽  
Germination Inhibition ◽  
Industry Professionals ◽  
The U.S

Boxwood is one of the most common and widely planted perennial ornamentals in both home gardens and commercial landscapes. Recently reported boxwood dieback, a fungal disease caused by Colletotrichum theobromicola, has been spreading at an alarming rate within the U.S. Boxwood breeders, nursery growers, and landscape professionals have shown great concerns regarding the lack of effective management practices. Therefore, the primary objectives of this study were to devise effective disease management strategies including screening cultivars to determine their susceptibility to boxwood dieback and screening various fungicides to determine their effectiveness in managing the disease. Host range studies were conducted by screening a wide variety of boxwood cultivars under greenhouse conditions. Although, boxwood cultivar ‘Little Missy’ showed much delayed symptom expression as compared to rest of the cultivars but none of the 11 cultivars were found to be resistance to boxwood dieback. In vitro screening of nine fungicides was conducted to determine mycelial growth as well as spore germination inhibition of eight isolates of C. theobromicola collected from eight states in the U.S. Of the nine fungicides, difenoconazole+pydiflumetofen showed maximum mycelial growth and spore germination inhibition at 1 ppm active ingredient followed by fluxapyroxad+pyraclostrobin, and pyraclostrobin+boscalid at 5 ppm active ingredient. Azoxystrobin+benzovindiflupyr significantly inhibited mycelial growth at 1 ppm but reduced spore germination at 10 ppm active ingredient. This study provides the boxwood industry professionals with critical and applied information pertaining to host susceptibility and fungicide efficacy to effectively mitigate boxwood dieback and to reduce its further spread.

Effects of Potassium Sorbate on Growth and Aflatoxin Production by Aspergillus parasiticus and Aspergillus flavus1

1983 ◽  
Vol 46 (11) ◽  
pp. 940-942 ◽  
Author(s):  
LLOYD B. BULLERMAN
Keyword(s):  
Aspergillus Flavus ◽  
Yeast Extract ◽  
Aflatoxin B1 ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Aspergillus Parasiticus ◽  
Aflatoxin Production ◽  
Potassium Sorbate ◽  
Mycelial Mass ◽  
Yeast Extract Sucrose

Growth and aflatoxin production by selected strains of Aspergillus parasiticus and Aspergillus flavus in the presence of potassium sorbate at 12°C were studied. Potassium sorbate at 0.05, 0.10 and 0.15% delayed or prevented spore germination and initiation of growth, and slowed growth of these organisms in yeast-extract sucrose broth at 12°C. Increasing concentrations of sorbate caused more variation in the amount of total mycelial growth and generally resulted in a decrease in total mycelial mass. Potassium sorbate also greatly reduced or prevented production of aflatoxin B1 by A. parasiticus and A. flavus for up to 70 d at 12°C. At 0.10 and 0.15% of sorbate, aflatoxin production was essentially eliminated. A 0.05% sorbate, aflatoxin production was greatly decreased in A. flavus over the control, but only slightly decreased in A. parasiticus.

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

Sign in / Sign up

Export Citation Format

Share Document