Survey of Spilocaea oleagina, causal agent of olive leaf spot, in North of Iran

2011 ◽  
Vol 2 (3) ◽  
Author(s):  
S. J. Sanei
Keyword(s):  
Leaf Spot ◽  
Causal Agent ◽  
Olive Leaf ◽  
North Of Iran

scholarly journals Laminarin Induces Defense Responses and Efficiently Controls Olive Leaf Spot Disease in Olive

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1043
Author(s):  
George T. Tziros ◽  
Anastasios Samaras ◽  
George S. Karaoglanidis
Keyword(s):  
Leaf Spot ◽  
Defense Responses ◽  
Copper Accumulation ◽  
Leaf Spot Disease ◽  
Biological Control Agents ◽  
Olive Leaf ◽  
Control Efficacy ◽  
Resistance Inducers ◽  
Kinetics Of ◽  
Potential Use

Olive leaf spot (OLS) caused by Fusicladiumoleagineum is mainly controlled using copper fungicides. However, the replacement of copper-based products with eco-friendly alternatives is a priority. The use of plant resistance-inducers (PRIs) or biological control agents (BCAs) could contribute in this direction. In this study we investigated the potential use of three PRIs (laminarin, acibenzolar-S-methyl, harpin) and a BCA (Bacillus amyloliquefaciens FZB24) for the management of OLS. The tested products provided control efficacy higher than 68%. In most cases, dual applications provided higher (p < 0.05) control efficacies compared to that achieved by single applications. The highest control efficacy of 100% was achieved by laminarin. Expression analysis of the selected genes by RT-qPCR revealed different kinetics of induction. In laminarin-treated plants, for most of the tested genes a higher induction rate (p < 0.05) was observed at 3 days post application. Pal, Lox, Cuao and Mpol were the genes with the higher inductions in laminarin-treated and artificially inoculated plants. The results of this study are expected to contribute towards a better understanding of PRIs in olive culture and the optimization of OLS control, while they provide evidence for potential contributions in the reduction of copper accumulation in the environment.

Visible/Near infrared (VIS/NIR) spectroscopy and multivariate data analysis (MVDA) for identification and quantification of olive leaf spot (OLS) disease

2014 ◽  
Vol 2 (1) ◽  
pp. 1-9
Author(s):  
Nawaf Abu-Khalaf ◽  
Mazen Salman
Keyword(s):  
Leaf Spot ◽  
Near Infrared ◽  
Latent Infection ◽  
Linear Method ◽  
Nir Spectroscopy ◽  
Support Vector ◽  
Olive Leaf ◽  
Classification Rate ◽  
Infection Period ◽  
Linear Svm

Early detection of plant disease requires usually elaborating methods techniques and especially when symptoms are not visible. Olive Leaf Spot (OLS) infecting upper surface of olive leaves has a long latent infection period. In this work, VIS/NIR spectroscopy was used to determine the latent infection and severity of the pathogens. Two different classification methods were used, Partial Least Squared-Discrimination Analysis (PLS-DA) (linear method) and Support Vector Machine (SVM) (non-linear). SVM-classification was able to classify severity levels 0, 1, 2, 3, 4, and 5 with classification rates of 94, 90, 73, 79, 83 and 100%, respectively The overall classification rate was about 86%. PLS-DA was able to classify two different severity groups (first group with severity 0, 1, 2, 3, and second group with severity 4, 5), with a classification rate greater than 95%. The results promote further researches, and the possibility of evaluation OLS in-situ using portable VIS/NIR devices.

Visible/Near infrared (VIS/NIR) spectroscopy and multivariate data analysis (MVDA) for identification and quantification of olive leaf spot (OLS) disease

2014 ◽  
Vol 2 (1) ◽  
pp. 1-9
Author(s):  
Nawaf Abu-Khalaf ◽  
Mazen Salman
Keyword(s):  
Leaf Spot ◽  
Near Infrared ◽  
Latent Infection ◽  
Linear Method ◽  
Nir Spectroscopy ◽  
Support Vector ◽  
Olive Leaf ◽  
Classification Rate ◽  
Infection Period ◽  
Linear Svm

Early detection of plant disease requires usually elaborating methods techniques and especially when symptoms are not visible. Olive Leaf Spot (OLS) infecting upper surface of olive leaves has a long latent infection period. In this work, VIS/NIR spectroscopy was used to determine the latent infection and severity of the pathogens. Two different classification methods were used, Partial Least Squared-Discrimination Analysis (PLS-DA) (linear method) and Support Vector Machine (SVM) (non-linear). SVM-classification was able to classify severity levels 0, 1, 2, 3, 4, and 5 with classification rates of 94, 90, 73, 79, 83 and 100%, respectively The overall classification rate was about 86%. PLS-DA was able to classify two different severity groups (first group with severity 0, 1, 2, 3, and second group with severity 4, 5), with a classification rate greater than 95%. The results promote further researches, and the possibility of evaluation OLS in-situ using portable VIS/NIR devices.

scholarly journals In vitro effects of fungicides on conidium germination of Spilocaea oleagina the cause of olive leaf spot

2005 ◽  
Vol 58 ◽  
pp. 278-282
Author(s):  
E.O. Obanor ◽  
M. Walter ◽  
E.E. Jones ◽  
M.V. Jaspers
Keyword(s):  
Leaf Spot ◽  
Copper Hydroxide ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Benzimidazole Fungicides ◽  
Low Concentrations ◽  
Conidium Germination ◽  
In Vitro Effects ◽  
Demethylation Inhibitor

Twenty fungicides were tested in vitro for their effects on the germination of conidia of Spilocaea oleagina the fungus that causes olive leaf spot Conidia used in this evaluation were obtained from naturally infected olive leaves in Canterbury Of the fungicides tested kresoximmethyl and captan were the most effective in preventing conidium germination at low concentrations with EC50 values of 0002 and 0003 g/ml respectively The newer fungicides boscalid and boscalid/pyraclostrobin were also effective (EC500031 and 0006 g/ml respectively) Of the benzimidazole fungicides tested carbendazim was effective (EC500005 g/ml) but thiophanatemethyl was not (EC5026 g/ml) None of the demethylation inhibitor fungicides tested were very effective (EC50 values gt;1 g/ml) except flusilazol (EC500075 g/ml) Two coppercontaining fungicides copper hydroxide and copper sulphate were ineffective for preventing conidium germination (EC5030 and 443 g/ml respectively) This study has identified candidate fungicides for further evaluation as tools for management of olive leaf spot

scholarly journals Antagonistic Action of Bacillus sp. AB89 to Phloeospora maculans, Causal Agent of Mulberry Leaf Spot

10.5109/24278 ◽  
1999 ◽  
Vol 43 (3/4) ◽  
pp. 337-342
Author(s):  
Kyung-Hee Kim ◽  
Shino Inoue ◽  
Masakazu Kawanami ◽  
Naruto Furuya ◽  
Nobuaki Matsuyama
Keyword(s):  
Leaf Spot ◽  
Causal Agent ◽  
Bacillus Sp ◽  
Antagonistic Action ◽  
Mulberry Leaf

Asterobolus: a new parasitic hyphomycete with a novel dispersal mechanism

1972 ◽  
Vol 50 (3) ◽  
pp. 409-412 ◽  
Author(s):  
Scott A. Redhead ◽  
Peter W. Perrin
Keyword(s):  
Leaf Spot ◽  
Causal Agent ◽  
Sporogenous Cell ◽  
Gaultheria Shallon ◽  
Dispersal Mechanism ◽  
Conidial Stage

The genus Asterobolus is proposed for an undescribed hyphomycete characterized by multicelled, star-shaped conidia forcibly discharged by a downfolding of the radiating appendages and rupture of the sporogenous cell. Asterobolus gaultheriae sp. nov. is the causal agent of a leaf spot of Gaultheria shallon Pursh. The fungus also infects species of Vaccinium, Pteridium, Malus, and Menziesia. Sclerotia were observed only on Gaultheria and infections of other hosts were found only near infected Gaultheria. In addition to the star-shaped conidia, a Gliocladium-like conidial stage was also observed in cultures of the fungus.

Lophomerum ponticum. [Descriptions of Fungi and Bacteria].

1984 ◽  
Author(s):  
D. W. Minter
Keyword(s):  
Great Britain ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Causal Agent ◽  
Leaf Spot Disease ◽  
Spot Disease ◽  
Green Leaves ◽  
Rhododendron Ponticum

Abstract A description is provided for Lophomerum ponticum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Rhododendron ponticum. DISEASE: Leaf spot of rhododendron. In general Lophomerum ponticum appears to be saprophytic. Its ascocarps are usually not produced until the leaves have senesced, become detached and fallen to the litter. Occasionally, however, ascocarps can be found on browned regions of otherwise green leaves, and it seems possible, therefore, that the species is facultatively parasitic. It is important to distinguish this species from Lophodermium vagulum (CMI Descriptions 789) which is the causal agent of a leaf spot disease of chinese rhododendrons, but which does not occur on R. ponticum. GEOGRAPHICAL DISTRIBUTION: Europe (Great Britain), probably much more widespread. TRANSMISSION: By air-borne ascospores in wet or humid weather.

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