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Prof. Imre Holb
1. Institute of Horticulture, University of Debrecen, Debrecen, Hungary

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0 Integrated Pest Management
0 Plant Pathology
0 plant disease epidemiology
0 plant disease management
0 Disease warning and forecasting

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Journal article
Published: 03 July 2021 in Agronomy
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Irrigation is a key factor for different physiological aspects of fruit trees. Therefore, such irrigation protocols that can save water consumption during irrigation and maintain fruit trees productivity are an essential goal especially under semiarid climate conditions. The aim of this 3-year apricot study was to investigate the effect of four deficit irrigation (DI) treatments (control, moderate regulated deficit irrigation: RDIm, severe RDI: RDIs and continuous DI: CDI) on 15 tree physiological properties (chilling requirement—CR, heat requirement—HR, days from end—dormancy until fruit harvest—DEDFH, sum of growing degree days—sGDD, total number of buds—TNB, number of flower buds—NFB, number of vegetative buds—NVB, starting date of flowering—SDF, number of opened flower buds—NOFB, flower bud abscission—FBA, fruit set—FS, seasonal vegetative growth—SVG, fruit number per tree—FNT, fruit weight—FW, fruit yield—FY), and on two tree chemical properties (total soluble carbohydrates—TSC and total proline content—TPC) on apricot cultivars ‘Ninfa’ and ‘Canino’ in Egypt. Results showed that both DI treatments and cultivars significantly influenced the values of CR, HR, TNB, SDF, NOFB, FS, SVG, FNT, FY, TSC, and TPC. Values of FBA were significantly affected by years and DI treatments, while sGDD by years and cultivars. Values of DEDFH, NFB, and FW were significantly influenced only by cultivars, while NVB only by DI treatments. The RDIm treatment gave the most acceptable values for most measured properties compared to the fully irrigated control treatment. Prediction based model analysis demonstrated that generalized linear models (GLMs) can be predictors for the measured tree properties in the DI treatments. The best goodness-of-fit of the predicted GLMs was reached for HR, NOFB, FS, SVG, FNT, TSC, and TPC. In all the four DI treatments, 22 pair-variables (TNB versus (vs.) NFB, TNB vs. NOFB, TNB vs. NOFB, NFB vs. NOFB, NFB vs. FNT, NFB vs. FY, NFB vs. FW, NOFB vs. SVG, NOFB vs. FNT, NOFB vs. FY, FS vs. FNT, FS vs. FY, SVG vs. FNT, SVG vs. FY, SVG vs. TSC, FNT vs. FY, FY vs. FW, CR vs. TSC, HR vs. TNB, HR vs. NFB, HR vs. FNT, HR vs. FY, and NOFB vs. FBA) correlated significantly in Pearson correlation and regression analyses. Principal component analyses explained 82% of the total variance and PC1, PC2, and PC3 explained 23, 21, and 15% of the total variance and correlated with the HR, TNB, FS, FNT and FY; FBA, SVG, TSC, and TPC; and NFB, NVB and NOFB, respectively, indicating strong connections among tree physiological and chemical properties. In conclusion, DI techniques using moderate water deficits can be managed successfully in apricot production under semiarid Mediterranean climate conditions such as the one in Egypt.

ACS Style

Ahmed Ezzat; Abdel-Moety Salama; Szilárd Szabó; Arshad Yaseen; Bianka Molnár; Imre Holb. Deficit Irrigation Strategies on Tree Physiological and Chemical Properties: Treatment Effects, Prediction Based Model Analyses and Inter-Correlations. Agronomy 2021, 11, 1361 .

AMA Style

Ahmed Ezzat, Abdel-Moety Salama, Szilárd Szabó, Arshad Yaseen, Bianka Molnár, Imre Holb. Deficit Irrigation Strategies on Tree Physiological and Chemical Properties: Treatment Effects, Prediction Based Model Analyses and Inter-Correlations. Agronomy. 2021; 11 (7):1361.

Chicago/Turabian Style

Ahmed Ezzat; Abdel-Moety Salama; Szilárd Szabó; Arshad Yaseen; Bianka Molnár; Imre Holb. 2021. "Deficit Irrigation Strategies on Tree Physiological and Chemical Properties: Treatment Effects, Prediction Based Model Analyses and Inter-Correlations." Agronomy 11, no. 7: 1361.

Journal article
Published: 09 May 2021 in Agronomy
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In both arid and semiarid regions, erosion by wind is a significant threat against sustainability of natural resources. The objective of this work was to investigate the direct impact of various soil moisture levels with soil texture and organic matter on soil crust formation and evaporation. Eighty soil samples with different texture (sand: 19, loamy sand: 21, sandy loam: 26, loam: 8, and silty loam: 6 samples) were collected from the Nyírség region (Eastern Hungary). A wind tunnel experiment was conducted on four simulated irrigation rates (0.5, l.0, 2.0, and 5.0 mm) and four levels of wind speeds (4.5, 7.8, 9.2, and 15.5 m s−1). Results showed that watering with a quantity equal to 5 mm rainfall, with the exception of sandy soils, provided about 5–6 h protection against wind erosion, even in case of a wind velocity as high as 15.5 m s−1. An exponential connection was revealed between wind velocities and the times of evaporation (R2 = 0.88–0.99). Notably, a two-way ANOVA test revealed that both wind velocity (p < 0.001) and soil texture (p < 0.01) had a significant effect on the rate of evaporation, but their interaction was not significant (p = 0.26). In terms of surface crusts, silty loamy soils resulted in harder and more solid crusts in comparison with other textures. In contrast, crust formation in sandy soils was almost negligible, increasing their susceptibility to wind erosion risk. These results can support local municipalities in the development of a local plan against wind erosion phenomena in agricultural areas.

ACS Style

Gábor Négyesi; Szilárd Szabó; Botond Buró; Safwan Mohammed; József Lóki; Kálmán Rajkai; Imre Holb. Influence of Soil Moisture and Crust Formation on Soil Evaporation Rate: A Wind Tunnel Experiment in Hungary. Agronomy 2021, 11, 935 .

AMA Style

Gábor Négyesi, Szilárd Szabó, Botond Buró, Safwan Mohammed, József Lóki, Kálmán Rajkai, Imre Holb. Influence of Soil Moisture and Crust Formation on Soil Evaporation Rate: A Wind Tunnel Experiment in Hungary. Agronomy. 2021; 11 (5):935.

Chicago/Turabian Style

Gábor Négyesi; Szilárd Szabó; Botond Buró; Safwan Mohammed; József Lóki; Kálmán Rajkai; Imre Holb. 2021. "Influence of Soil Moisture and Crust Formation on Soil Evaporation Rate: A Wind Tunnel Experiment in Hungary." Agronomy 11, no. 5: 935.

Journal article
Published: 28 April 2021 in Journal of Fungi
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Monilinia laxa causes serious postharvest damage on apricot fruits under shelf-life storage conditions. Plant elicitors of methyl jasmonate (MeJA) and salicylic acid (SA) can reduce this damage, and their research can explain the background of the plant defense physiological processes in M. laxa-infected fruits. The aims of this study were: (i) to evaluate the effect of various concentrations of MeJA and SA on brown rot incidence (BRI) and lesion diameter (LD) of apricot fruits; (ii) to measure the temporal patterns for the effect of 0.4 mmol L−1 MeJA and 2 mmol L−1 SA treatments on BRI, LD and seven fruit measures (fruit firmness (FF), lignin content (LC), total soluble phenol content (TSPC), total antioxidant capacity (TAC) and enzyme activities of PAL, POD and SOD) in treatments of M. laxa-inoculated versus (vs.) non-inoculated fruits over an eight-day shelf-life storage period; and (iii) to determine inter-correlations among the seven fruit measures for MeJA and SA treatments. Both MeJA and SA significantly reduced BRI and LD. LC, FF, TAC, TSPC, as well as SOD and PAL activities in the MeJA and SA treatments were higher than the water-treated control in most assessment days and both inoculation treatments. In both inoculation treatments, the activity of POD in the SA-treated fruits was higher than MeJA-treated and control fruits at all dates. In MeJA vs. SA and inoculated vs. non-inoculated treatments, six variable pairs (FF vs. TSPC, FF vs. TAC, TAC vs. PAL, PAL vs. POD, PAL vs. SOD, and POD vs. SOD) showed significant inter-correlation values. Principal component analyses explained 96% and 93% of the total variance for inoculated and non-inoculated treatments, respectively. In inoculated treatments, both PC1 and PC2 explained 41% of the total variance and correlated with FF, TSPC and TAC and with PAL, SOD and POD, respectively. In non-inoculated treatments, PC1 and PC2 explained 49% and 44% of the total variance and correlated with LC, PAL, POD and SOD and with FF, TSPC and TAC, respectively. It can be concluded that MeJA and SA are useful in the practice to enhance the plant defense system against brown rot by reducing fungal growth and by improving physical and antioxidant attributes (FF, LC, TAC and TSPC) and the activity of defense-related enzymes (PAL, POD and SOD) in apricot fruits during shelf-life storage conditions.

ACS Style

Ahmed Ezzat; Szilárd Szabó; Zoltán Szabó; Attila Hegedűs; Dorina Berényi; Imre Holb. Temporal Patterns and Inter-Correlations among Physical and Antioxidant Attributes and Enzyme Activities of Apricot Fruit Inoculated with Monilinia laxa under Salicylic Acid and Methyl Jasmonate Treatments under Shelf-Life Conditions. Journal of Fungi 2021, 7, 341 .

AMA Style

Ahmed Ezzat, Szilárd Szabó, Zoltán Szabó, Attila Hegedűs, Dorina Berényi, Imre Holb. Temporal Patterns and Inter-Correlations among Physical and Antioxidant Attributes and Enzyme Activities of Apricot Fruit Inoculated with Monilinia laxa under Salicylic Acid and Methyl Jasmonate Treatments under Shelf-Life Conditions. Journal of Fungi. 2021; 7 (5):341.

Chicago/Turabian Style

Ahmed Ezzat; Szilárd Szabó; Zoltán Szabó; Attila Hegedűs; Dorina Berényi; Imre Holb. 2021. "Temporal Patterns and Inter-Correlations among Physical and Antioxidant Attributes and Enzyme Activities of Apricot Fruit Inoculated with Monilinia laxa under Salicylic Acid and Methyl Jasmonate Treatments under Shelf-Life Conditions." Journal of Fungi 7, no. 5: 341.

Review
Published: 19 April 2021 in Horticulturae
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Adequate chill is of great importance for successful production of deciduous fruit trees. However, temperate fruit trees grown under tropical and subtropical regions may face insufficient winter chill, which has a crucial role in dormancy and productivity. The objective of this review is to discuss the challenges for dormancy and chilling requirements of temperate fruit trees, especially in warm winter regions, under climate change conditions. After defining climate change and dormancy, the effects of climate change on various parameters of temperate fruit trees are described. Then, dormancy breaking chemicals and organic compounds, as well as some aspects of the mechanism of dormancy breaking, are demonstrated. After this, the relationships between dormancy and chilling requirements are delineated and challenging aspects of chilling requirements in climate change conditions and in warm winter environments are demonstrated. Experts have sought to develop models for estimating chilling requirements and dormancy breaking in order to improve the adaption of temperate fruit trees under tropical and subtropical environments. Some of these models and their uses are described in the final section of this review. In conclusion, global warming has led to chill deficit during winter, which may become a limiting factor in the near future for the growth of temperate fruit trees in the tropics and subtropics. With the increasing rate of climate change, improvements in some managing tools (e.g., discovering new, more effective dormancy breaking organic compounds; breeding new, climate-smart cultivars in order to solve problems associated with dormancy and chilling requirements; and improving dormancy and chilling forecasting models) have the potential to solve the challenges of dormancy and chilling requirements for temperate fruit tree production in warm winter fruit tree growing regions.

ACS Style

Abdel-Moety Salama; Ahmed Ezzat; Hassan El-Ramady; Shamel Alam-Eldein; Sameh Okba; Hayam Elmenofy; Islam Hassan; Attila Illés; Imre Holb. Temperate Fruit Trees under Climate Change: Challenges for Dormancy and Chilling Requirements in Warm Winter Regions. Horticulturae 2021, 7, 86 .

AMA Style

Abdel-Moety Salama, Ahmed Ezzat, Hassan El-Ramady, Shamel Alam-Eldein, Sameh Okba, Hayam Elmenofy, Islam Hassan, Attila Illés, Imre Holb. Temperate Fruit Trees under Climate Change: Challenges for Dormancy and Chilling Requirements in Warm Winter Regions. Horticulturae. 2021; 7 (4):86.

Chicago/Turabian Style

Abdel-Moety Salama; Ahmed Ezzat; Hassan El-Ramady; Shamel Alam-Eldein; Sameh Okba; Hayam Elmenofy; Islam Hassan; Attila Illés; Imre Holb. 2021. "Temperate Fruit Trees under Climate Change: Challenges for Dormancy and Chilling Requirements in Warm Winter Regions." Horticulturae 7, no. 4: 86.

Journal article
Published: 25 February 2021 in Remote Sensing
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We analyzed the Corine Land Cover 2018 (CLC2018) dataset to reveal the correspondence between land cover categories of the CLC and the spectral information of Landsat-8, Sentinel-2 and PlanetScope images. Level 1 categories of the CLC2018 were analyzed in a 25 km × 25 km study area in Hungary. Spectral data were summarized by land cover polygons, and the dataset was evaluated with statistical tests. We then performed Linear Discriminant Analysis (LDA) and Random Forest classifications to reveal if CLC L1 level categories were confirmed by spectral values. Wetlands and water bodies were the most likely to be confused with other categories. The least mixture was observed when we applied the median to quantify the pixel variance of CLC polygons. RF outperformed the LDA’s accuracy, and PlanetScope’s data were the most accurate. Analysis of class level accuracies showed that agricultural areas and wetlands had the most issues with misclassification. We proved the representativeness of the results with a repeated randomized test, and only PlanetScope seemed to be ungeneralizable. Results showed that CLC polygons, as basic units of land cover, can ensure 71.1–78.5% OAs for the three satellite sensors; higher geometric resolution resulted in better accuracy. These results justified CLC polygons, in spite of visual interpretation, can hold relevant information about land cover considering the surface reflectance values of satellites. However, using CLC as ground truth data for land cover classifications can be questionable, at least in the L1 nomenclature.

ACS Style

Orsolya Varga; Zoltán Kovács; László Bekő; Péter Burai; Zsuzsanna Csatáriné Szabó; Imre Holb; Sarawut Ninsawat; Szilárd Szabó. Validation of Visually Interpreted Corine Land Cover Classes with Spectral Values of Satellite Images and Machine Learning. Remote Sensing 2021, 13, 857 .

AMA Style

Orsolya Varga, Zoltán Kovács, László Bekő, Péter Burai, Zsuzsanna Csatáriné Szabó, Imre Holb, Sarawut Ninsawat, Szilárd Szabó. Validation of Visually Interpreted Corine Land Cover Classes with Spectral Values of Satellite Images and Machine Learning. Remote Sensing. 2021; 13 (5):857.

Chicago/Turabian Style

Orsolya Varga; Zoltán Kovács; László Bekő; Péter Burai; Zsuzsanna Csatáriné Szabó; Imre Holb; Sarawut Ninsawat; Szilárd Szabó. 2021. "Validation of Visually Interpreted Corine Land Cover Classes with Spectral Values of Satellite Images and Machine Learning." Remote Sensing 13, no. 5: 857.

Journal article
Published: 13 February 2021 in Agronomy
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Gullies are responsible for detaching massive volumes of productive soil, dissecting natural landscape and causing damages to infrastructure. Despite existing research, the gravity of the gully erosion problem underscores the urgent need for accurate mapping of gullies, a first but essential step toward sustainable management of soil resources. This study aims to obtain the spatial distribution of gullies through comparing various classifiers: k-dimensional tree K-Nearest Neighbor (k-d tree KNN), Minimum Distance (MD), Maximum Likelihood (ML), and Random Forest (RF). Results indicated that all the classifiers, with the exception of ML, achieved an overall accuracy (OA) of at least 0.85. RF had the highest OA (0.94), although it was outperformed in gully identification by MD (0% commission), but the omission error was 20% (MD). Accordingly, RF was considered as the best algorithm, having 13% error in both adding (commission) and omitting pixels as gullies. Thus, RF ensured a reliable outcome to map the spatial distribution of gullies. RF-derived gully density map reflected the agricultural areas most exposed to gully erosion. Our approach of using satellite imagery has certain limitations, and can be used only in arid or semiarid regions where gullies are not covered by dense vegetation as the vegetation biases the extracted gullies. The approach also provides a solution to the lack of laser scanned data, especially in the context of the study area, providing better accuracy and wider application possibilities.

ACS Style

Kwanele Phinzi; Imre Holb; Szilárd Szabó. Mapping Permanent Gullies in an Agricultural Area Using Satellite Images: Efficacy of Machine Learning Algorithms. Agronomy 2021, 11, 333 .

AMA Style

Kwanele Phinzi, Imre Holb, Szilárd Szabó. Mapping Permanent Gullies in an Agricultural Area Using Satellite Images: Efficacy of Machine Learning Algorithms. Agronomy. 2021; 11 (2):333.

Chicago/Turabian Style

Kwanele Phinzi; Imre Holb; Szilárd Szabó. 2021. "Mapping Permanent Gullies in an Agricultural Area Using Satellite Images: Efficacy of Machine Learning Algorithms." Agronomy 11, no. 2: 333.

Journal article
Published: 14 November 2020 in Applied Sciences
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The apricot storability is one of the largest challenges, which the apricot industry has to face all over the world; therefore, finding options for prolonging fruit quality during cold storage (CS) and shelf-life (SL) will help to decrease postharvest losses of apricot. The aim of this apricot fruit work was to study the temporal changes and correlations of 10 quality parameters (quality losses, antioxidant properties and enzyme activities) in the postharvest treatments of methyl jasmonate (MeJA) and salicylic acid (SA) under 1 °C CS (7, 14 and 21 days) and 25 °C SL (4 and 8 days after the 21-day CS) treatments. MeJA and SA significantly decreased the quality loss of chilling injury (CI) and fruit decay (FD) at all dates for both storage conditions. MeJA- and SA-treated fruits increased total antioxidant capacity (TAC), total soluble phenolic compounds (TSPC) and carotenoids contents (TCC) at all dates of both storage treatments. In contrast, the ascorbic acid content (AAC) increased only until days 14 and 4 in the CS and SL treatments, respectively. Among enzyme activity parameters, the activities of phenylalanine ammonia-lyase (PAL), peroxidase and superoxide dismutase (SOD) were significantly increased in the MeJA and SA treatments in all dates of both storage treatments. Catalase (CAT) activity increased in the SA and control treatments, while it decreased in the MeJA treatment in both storage conditions. In both the MeJA and the SA treatments, six pair-variables (FD vs. CI, PAL vs. CAT, PAL vs. SOD, TAC vs. SOD, TAC vs. FD, and AAC vs. CI) were significant in Pearson correlation and regression analyses among the 45 parameters pairs. Principal component analyses explained 89.3% of the total variance and PC1 accounted for 55.6% of the variance and correlated with the CI, FD, TAC, TSPC, TCC, PAL and SOD, indicating strong connections among most parameters. In conclusion, MeJA and SA are practically useful and inexpensive techniques to maintain quality attributes of CI, FD, TAC, TSPC, TCC, PAL, POD and SOD in apricot fruit during both CS and SL conditions.

ACS Style

Ahmed Ezzat; Attila Hegedűs; Szilárd Szabó; Amin Ammar; Zoltán Szabó; József Nyéki; Bianka Molnár; Imre J. Holb. Temporal Changes and Correlations between Quality Loss Parameters, Antioxidant Properties and Enzyme Activities in Apricot Fruit Treated with Methyl Jasmonate and Salicylic Acid during Cold Storage and Shelf-Life. Applied Sciences 2020, 10, 8071 .

AMA Style

Ahmed Ezzat, Attila Hegedűs, Szilárd Szabó, Amin Ammar, Zoltán Szabó, József Nyéki, Bianka Molnár, Imre J. Holb. Temporal Changes and Correlations between Quality Loss Parameters, Antioxidant Properties and Enzyme Activities in Apricot Fruit Treated with Methyl Jasmonate and Salicylic Acid during Cold Storage and Shelf-Life. Applied Sciences. 2020; 10 (22):8071.

Chicago/Turabian Style

Ahmed Ezzat; Attila Hegedűs; Szilárd Szabó; Amin Ammar; Zoltán Szabó; József Nyéki; Bianka Molnár; Imre J. Holb. 2020. "Temporal Changes and Correlations between Quality Loss Parameters, Antioxidant Properties and Enzyme Activities in Apricot Fruit Treated with Methyl Jasmonate and Salicylic Acid during Cold Storage and Shelf-Life." Applied Sciences 10, no. 22: 8071.

Journal article
Published: 07 October 2020 in Water
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Soils in the coastal region of Syria (CRoS) are one of the most fragile components of natural ecosystems. However, they are adversely affected by water erosion processes after extreme land cover modifications such as wildfires or intensive agricultural activities. The main goal of this research was to clarify the dynamic interaction between erosion processes and different ecosystem components (inclination, land cover/land use, and rainy storms) along with the vulnerable territory of the CRoS. Experiments were carried out in five different locations using a total of 15 erosion plots. Soil loss and runoff were quantified in each experimental plot, considering different inclinations and land uses (agricultural land (AG), burnt forest (BF), forest/control plot (F)). Observed runoff and soil loss varied greatly according to both inclination and land cover after 750 mm of rainfall (26 events). In the cultivated areas, the average soil water erosion ranged between 0.14 ± 0.07 and 0.74 ± 0.33 kg/m2; in the BF plots, mean soil erosion ranged between 0.03 ± 0.01 and 0.24 ± 0.10 kg/m2. The lowest amount of erosion was recorded in the F plots where the erosion ranged between 0.1 ± 0.001 and 0.07 ± 0.03 kg/m2. Interestingly, the General Linear Model revealed that all factors (i.e., inclination, rainfall and land use) had a significant (p < 0.001) effect on the soil loss. We concluded that human activities greatly influenced soil erosion rates, being higher in the AG lands, followed by BF and F. Therefore, the current study could be very useful to policymakers and planners for proposing immediate conservation or restoration plans in a less studied area which has been shown to be vulnerable to soil erosion processes.

ACS Style

Safwan Mohammed; Hazem G. Abdo; Szilard Szabo; Quoc Bao Pham; Imre J. Holb; Nguyen Thi Thuy Linh; Duong Tran Anh; Karam Alsafadi; Ali Mokhtar; Issa Kbibo; Jihad Ibrahim; Jesus Rodrigo-Comino. Estimating Human Impacts on Soil Erosion Considering Different Hillslope Inclinations and Land Uses in the Coastal Region of Syria. Water 2020, 12, 2786 .

AMA Style

Safwan Mohammed, Hazem G. Abdo, Szilard Szabo, Quoc Bao Pham, Imre J. Holb, Nguyen Thi Thuy Linh, Duong Tran Anh, Karam Alsafadi, Ali Mokhtar, Issa Kbibo, Jihad Ibrahim, Jesus Rodrigo-Comino. Estimating Human Impacts on Soil Erosion Considering Different Hillslope Inclinations and Land Uses in the Coastal Region of Syria. Water. 2020; 12 (10):2786.

Chicago/Turabian Style

Safwan Mohammed; Hazem G. Abdo; Szilard Szabo; Quoc Bao Pham; Imre J. Holb; Nguyen Thi Thuy Linh; Duong Tran Anh; Karam Alsafadi; Ali Mokhtar; Issa Kbibo; Jihad Ibrahim; Jesus Rodrigo-Comino. 2020. "Estimating Human Impacts on Soil Erosion Considering Different Hillslope Inclinations and Land Uses in the Coastal Region of Syria." Water 12, no. 10: 2786.

Journal article
Published: 10 September 2020 in Water
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The Mediterranean part of Syria is affected by soil water erosion due to poor land management. Within this context, the main aim of this research was to track soil erosion and runoff after each rainy storm between September 2013 and April 2014 (rainy season), on two slopes with different gradients (4.7%; 10.3%), under three soil cover types (SCTs): bare soil (BS), metal sieve cover (MC), and strip cropping (SC), in Central Syria. Two statistical multivariate models, the general linear model (GLM), and the random forest regression (RFR) were applied to reveal the importance of SCTs. Our results reveal that higher erosion rate, as well as runoff, were recorded in BS followed by MC, and SC. Accordingly, soil cover had a significant effect (p < 0.001) on soil erosion, and no significant difference was detected between MC and SC. Different combinations of slopes and soil cover had no effect on erosion, at least in this experiment. RFR performed better than GLM in predictions. GLM’s median of mean absolute error was 21% worse than RFR. Nonetheless, 25 repetitions of 2-fold cross-validation ensured the highest available prediction accuracy for RFR. In conclusion, we revealed that runoff, rain intensity and soil cover were the most important factors in erosion.

ACS Style

Safwan Mohammed; Ali Al-Ebraheem; Imre Holb; Karam Alsafadi; Mohammad Dikkeh; Quoc Pham; Nguyen Linh; Szilard Szabo. Soil Management Effects on Soil Water Erosion and Runoff in Central Syria—A Comparative Evaluation of General Linear Model and Random Forest Regression. Water 2020, 12, 2529 .

AMA Style

Safwan Mohammed, Ali Al-Ebraheem, Imre Holb, Karam Alsafadi, Mohammad Dikkeh, Quoc Pham, Nguyen Linh, Szilard Szabo. Soil Management Effects on Soil Water Erosion and Runoff in Central Syria—A Comparative Evaluation of General Linear Model and Random Forest Regression. Water. 2020; 12 (9):2529.

Chicago/Turabian Style

Safwan Mohammed; Ali Al-Ebraheem; Imre Holb; Karam Alsafadi; Mohammad Dikkeh; Quoc Pham; Nguyen Linh; Szilard Szabo. 2020. "Soil Management Effects on Soil Water Erosion and Runoff in Central Syria—A Comparative Evaluation of General Linear Model and Random Forest Regression." Water 12, no. 9: 2529.

Journal article
Published: 17 April 2020 in ISPRS International Journal of Geo-Information
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Gullies reduce both the quality and quantity of productive land, posing a serious threat to sustainable agriculture, hence, food security. Machine Learning (ML) algorithms are essential tools in the identification of gullies and can assist in strategic decision-making relevant to soil conservation. Nevertheless, accurate identification of gullies is a function of the selected ML algorithms, the image and number of classes used, i.e., binary (two classes) and multiclass. We applied Linear Discriminant Analysis (LDA), Support Vector Machine (SVM), and Random Forest (RF) on a Systeme Pour l’Observation de la Terre (SPOT-7) image to extract gullies and investigated whether the multiclass (m) approach can offer better classification accuracy than the binary (b) approach. Using repeated k-fold cross-validation, we generated 36 models. Our findings revealed that, of these models, both RFb (98.70%) and SVMm (98.01%) outperformed the LDA in terms of overall accuracy (OA). However, the LDAb (99.51%) recorded the highest producer’s accuracy (PA) but had low corresponding user’s accuracy (UA) with 18.5%. The binary approach was generally better than the multiclass approach; however, on class level, the multiclass approach outperformed the binary approach in gully identification. Despite low spectral resolution, the pan-sharpened SPOT-7 product successfully identified gullies. The proposed methodology is relatively simple, but practically sound, and can be used to monitor gullies within and beyond the study region.

ACS Style

Kwanele Phinzi; Dávid Abriha; László Bertalan; Imre Holb; Szilárd Szabó. Machine Learning for Gully Feature Extraction Based on a Pan-Sharpened Multispectral Image: Multiclass vs. Binary Approach. ISPRS International Journal of Geo-Information 2020, 9, 252 .

AMA Style

Kwanele Phinzi, Dávid Abriha, László Bertalan, Imre Holb, Szilárd Szabó. Machine Learning for Gully Feature Extraction Based on a Pan-Sharpened Multispectral Image: Multiclass vs. Binary Approach. ISPRS International Journal of Geo-Information. 2020; 9 (4):252.

Chicago/Turabian Style

Kwanele Phinzi; Dávid Abriha; László Bertalan; Imre Holb; Szilárd Szabó. 2020. "Machine Learning for Gully Feature Extraction Based on a Pan-Sharpened Multispectral Image: Multiclass vs. Binary Approach." ISPRS International Journal of Geo-Information 9, no. 4: 252.

Journal article
Published: 07 April 2020 in Sensors
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Airborne light detection and ranging (LiDAR) scanning is a commonly used technology for representing the topographic terrain. As LiDAR point clouds include all surface features present in the terrain, one of the key elements for generating a digital terrain model (DTM) is the separation of the ground points. In this study, we intended to reveal the efficiency of different denoising approaches and an easy-to-use ground point classification technique in a floodplain with fluvial forms. We analyzed a point cloud from the perspective of the efficiency of noise reduction, parametrizing a ground point classifier (cloth simulation filter, CSF), interpolation methods and resolutions. Noise filtering resulted a wide range of point numbers in the models, and the number of points had moderate correlation with the mean accuracies (r = −0.65, p < 0.05), indicating that greater numbers of points had larger errors. The smallest differences belonged to the neighborhood-based noise filtering and the larger cloth size (5) and the smaller threshold value (0.2). The most accurate model was generated with the natural neighbor interpolation with the cloth size of 5 and the threshold of 0.2. These results can serve as a guide for researchers using point clouds when considering the steps of data preparation, classification, or interpolation in a flat terrain.

ACS Style

Zsuzsanna Szabó; Csaba Albert Tóth; Imre Holb; Szilárd Szabó. Aerial Laser Scanning Data as a Source of Terrain Modeling in a Fluvial Environment: Biasing Factors of Terrain Height Accuracy. Sensors 2020, 20, 2063 .

AMA Style

Zsuzsanna Szabó, Csaba Albert Tóth, Imre Holb, Szilárd Szabó. Aerial Laser Scanning Data as a Source of Terrain Modeling in a Fluvial Environment: Biasing Factors of Terrain Height Accuracy. Sensors. 2020; 20 (7):2063.

Chicago/Turabian Style

Zsuzsanna Szabó; Csaba Albert Tóth; Imre Holb; Szilárd Szabó. 2020. "Aerial Laser Scanning Data as a Source of Terrain Modeling in a Fluvial Environment: Biasing Factors of Terrain Height Accuracy." Sensors 20, no. 7: 2063.

Journal article
Published: 10 May 2019 in Scientia Horticulturae
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In a 3-year study, effects of six pre-storage rhizome treatments (thiophanate-methyl, iprodione, dimoxistrobin + boscalide, Trichoderma asperellum, charcoal dust and untreated control) were studied on rhizome bud numbers, disease incidence of rhizome, sprouted plant, leaf numbers and plant height for three Canna × generalis cultivars. The three chemical fungicide treatments showed clear differences from the untreated control for all the five measurements among cultivars and years. Bud numbers on rhizome ranged from 1.8 to 2.6, which were significantly higher in the three chemical control treatments (2.6) than in the untreated control (1.8). Disease incidences of rhizome were significantly lower in the chemical treatments (ranged from 5.4 to 22.9%) than T. asperellum, charcoal dust and untreated control treatments (ranged from 16.2 to 32.1%, from 21.9 to 32.7%, and from 27.8 to 43.3%, respectively). Sprouted plants were significantly higher in all chemical treatments ranged from 76.8 to 96.3% than the untreated control ranged from 43.2 to 62.3% for each year and cultivar. Leaf numbers and plant height were significantly higher in the chemical treatments (ranged from 16.0 to 22.4 and 86.8 to 161.1 cm, respectively) than the untreated control (ranged from 13.7 to 17.6 and 65.8 to 132.3 cm, respectively), for all the three cultivars, in all years. Pearson’s correlation analyses revealed four significant relationships among disease incidence of rhizome versus incidence of sprouted plants (r = -0.982, P = <0.0001), leaf numbers versus plant height (r = 0.842, P = 0.007), bud numbers on rhizome versus incidence of sprouted plants (r = 0.773, P = 0.017), and bud numbers on rhizome versus disease incidence of rhizome (r = -0.709, P = 0.033). The two strongest relationships were revealed further by linear regression analysis. Our results showed that pre-storage chemical treatments of C. × generalis rhizomes were essential for reducing diseases of rhizomes during storage as well as had positive effects on sprouted plant, leaf numbers and plant height during the season.

ACS Style

Anikó Zsiláné-André; Alex Vámos; Bianka Molnár; Ádám Szabolcs; Imre J. Holb. Effect of six pre-storage rhizome treatments on rhizome vitality and seasonal growth characteristics of three Canna × generalis cultivars. Scientia Horticulturae 2019, 254, 155 -162.

AMA Style

Anikó Zsiláné-André, Alex Vámos, Bianka Molnár, Ádám Szabolcs, Imre J. Holb. Effect of six pre-storage rhizome treatments on rhizome vitality and seasonal growth characteristics of three Canna × generalis cultivars. Scientia Horticulturae. 2019; 254 ():155-162.

Chicago/Turabian Style

Anikó Zsiláné-André; Alex Vámos; Bianka Molnár; Ádám Szabolcs; Imre J. Holb. 2019. "Effect of six pre-storage rhizome treatments on rhizome vitality and seasonal growth characteristics of three Canna × generalis cultivars." Scientia Horticulturae 254, no. : 155-162.

Article
Published: 30 April 2019 in European Journal of Plant Pathology
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The aims of this three-year study were firstly to investigate the effect of 3 years, three sampling months and two grape cultivars (cvs) on noble rot incidence in the field and on the mycelial growth rate of Botrytis cinerea isolates in vitro under three incubation temperatures, and secondly to show possible effects of years, sampling months and cultivars on eight morphological (four mycelial: M I-IV and four sclerotial: S I-IV) types of B. cinerea isolates incubated at 20 °C. In addition, the relationship between monthly noble rot incidences and morphological types was calculated. Analyses of variance indicated significant differences among years, months and cultivars for noble rot incidence. Noble rot incidences were significantly higher on cv. ‘Turán’ compared to cv. ‘Olaszrizling’ in November in all years. Noble rot incidences were significantly lower in September compared to values in November in all years. Analyses of variance indicated significant differences among years, months, and temperatures for mycelial growth rate but the differences among cultivars were non-significant. Mycelial growth rates at 15 and 25 °C were higher in 2013 compared to 2014 and 2015; however, the rates at 20 °C were higher in 2014 compared to 2013 and 2015. The overall mean growth rate was the highest in 2013 (76 mm) compared to either 2014 or 2015 (65 or 69 mm, respectively). Mycelial growth rates were significantly different between earlier (September) and later (November) sampling months in three cases: i) in 2013 at 15 °C, ii) in 2014 at 20 °C, and iii) in 2015 at 25 °C. Analyses of variance indicated significant differences among years and months for the frequency distribution of the morphological types but the differences among cultivars were non-significant. In general, the most frequent mycelial and sclerotial types were M I-III and S IV (means were 21.5, 16.1, 28.9, and 13.1%, respectively). Isolates of mycelial types were more frequent in 2013 (∑ M-type 82.2%) compared to 2015 (∑ M-type 57.1%). The frequency distributions of morphological types among sampling months showed differences between the earlier (September or/and October) and the later months (November) in 2013 for M I-III, S II and S IV types; in 2014 for M I, M III, M IV, S I, S III and S IV types; and in 2015 for M I, M IV and S I-IV types. Pearson correlation analyses revealed a significant positive relationship between morphological types (∑ S-type and ∑ M-type) and monthly noble rot incidences (r = 0.676 and P = 0.048). In summary, our results showed possible effects of year/sampling month on noble rot incidence in connection with mycelial growth rate and morphological types of B. cinerea strains isolated during noble rot development.

ACS Style

Júlia Hegyi-Kaló; Imre J. Holb; Szabina Lengyel; Ákos Juhász; Kálmán Zoltán Váczy. Effect of year, sampling month and grape cultivar on noble rot incidence, mycelial growth rate and morphological type of Botrytis cinerea during noble rot development. European Journal of Plant Pathology 2019, 155, 339 -348.

AMA Style

Júlia Hegyi-Kaló, Imre J. Holb, Szabina Lengyel, Ákos Juhász, Kálmán Zoltán Váczy. Effect of year, sampling month and grape cultivar on noble rot incidence, mycelial growth rate and morphological type of Botrytis cinerea during noble rot development. European Journal of Plant Pathology. 2019; 155 (1):339-348.

Chicago/Turabian Style

Júlia Hegyi-Kaló; Imre J. Holb; Szabina Lengyel; Ákos Juhász; Kálmán Zoltán Váczy. 2019. "Effect of year, sampling month and grape cultivar on noble rot incidence, mycelial growth rate and morphological type of Botrytis cinerea during noble rot development." European Journal of Plant Pathology 155, no. 1: 339-348.

Original article
Published: 30 August 2017 in Trees
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Five cultivar classification categories were determined from season-long powdery mildew disease progression in integrated and organic production systems. Parameters derived from the progress curve categories were suggested for disease warning improvements. The goal of this 12-year study was to evaluate the powdery mildew infection rates of nine resistant, nine commercial, and nine old apple cultivars in two production systems: integrated and organic. Cultivars were classified into five categories, from low to high, based on their shoot and fruit disease progress curves assessed during the season with the disease progress analysed separately in all five classification categories. Powdery mildew incidence at harvest had increased considerably more for both fruit and shoots in the organic than in the integrated plots, except for the shoots of cultivars ‘Reglindis’, ‘Reka’, ‘Rewena’, ‘Parker Pepin’, and ‘Kings of the Pippin’. Control efficacy was acceptable for all resistant and most old cultivars in both production systems (final disease incidence was below 7.5%), but the level of powdery mildew incidence at harvest was middle-to-high or high for cultivars ‘Idared’, ‘Jonagold’, ‘Jonathan’, ‘Jonica’ and ‘Royal Gala’ from the commercial cultivar group in both production systems. Cultivar categorization for powdery mildew showed that season-long disease progress was low for the old; low-to-middle for the resistant; and middle-to-high for the commercial cultivars. A three-parameter logistic function was fitted to the temporal progress data of each classification category. Then the upper asymptote (Yf), rate parameter (β), and inflection point (M) were estimated from the fitted function and the standardized area under the disease progress curves (AUDPCS) were also calculated. Results demonstrated that AUDPCS and partially Yf were able to differentiate the five mildew classification categories for both shoot and fruit in both production systems. Therefore, AUDPCS and Yf were suggested as input parameters in disease warning systems for measuring host resistance. Yields in the integrated plots were higher compared with those in the organic ones. Powdery mildew classification categories, together with yield, can contribute to a more appropriate cultivar selection for establishing orchards managed by environmentally friendly approaches.

ACS Style

Imre J. Holb. Categorization of apple cultivars based on seasonal powdery mildew disease progression in two disease management systems over 12 years. Trees 2017, 31, 1905 -1917.

AMA Style

Imre J. Holb. Categorization of apple cultivars based on seasonal powdery mildew disease progression in two disease management systems over 12 years. Trees. 2017; 31 (6):1905-1917.

Chicago/Turabian Style

Imre J. Holb. 2017. "Categorization of apple cultivars based on seasonal powdery mildew disease progression in two disease management systems over 12 years." Trees 31, no. 6: 1905-1917.

Journal article
Published: 01 July 2017 in Crop Protection
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Lorenzo Furlan; Vasileios Vasileiadis; Francesca Chiarini; Hilfred Huiting; Robert Leskovšek; Jaka Razinger; Imre J. Holb; Erica Sartori; Gregor Urek; Arnd Verschwele; Isadora Benvegnù; Maurizio Sattin. Risk assessment of soil-pest damage to grain maize in Europe within the framework of Integrated Pest Management. Crop Protection 2017, 97, 52 -59.

AMA Style

Lorenzo Furlan, Vasileios Vasileiadis, Francesca Chiarini, Hilfred Huiting, Robert Leskovšek, Jaka Razinger, Imre J. Holb, Erica Sartori, Gregor Urek, Arnd Verschwele, Isadora Benvegnù, Maurizio Sattin. Risk assessment of soil-pest damage to grain maize in Europe within the framework of Integrated Pest Management. Crop Protection. 2017; 97 ():52-59.

Chicago/Turabian Style

Lorenzo Furlan; Vasileios Vasileiadis; Francesca Chiarini; Hilfred Huiting; Robert Leskovšek; Jaka Razinger; Imre J. Holb; Erica Sartori; Gregor Urek; Arnd Verschwele; Isadora Benvegnù; Maurizio Sattin. 2017. "Risk assessment of soil-pest damage to grain maize in Europe within the framework of Integrated Pest Management." Crop Protection 97, no. : 52-59.

Journal article
Published: 30 June 2017 in Polish Journal of Food and Nutrition Sciences
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The aim of this study was to investigate the effect of methyl jasmonate and salicylic acid on 12 quality parameters of apricot fruit in treatments of cold storage (1°C for 7, 14 and 21 days) and shelf-life (4 and 8 days at 25°C after a 21-day cold storage treatment). Fruit quality parameters included 6 physico-chemical characteristics (weight loss, fruit firmness, total soluble solids, acidity, total soluble solids/acidity ratio and juice pH) and 6 sensory properties (skin and flesh colour, texture, taste, visual appearance and overall acceptability). Among physico-chemical characteristics, applications of 0.2 mmol/L methyl jasmonate and 2 mmol/L salicylic acid significantly reduced fruit weight loss, fruit softening and juice pH and maintained soluble solid content and acidity over the whole storage period. Among sensory properties, all parameters were generally increased by methyl jasmonate and salicylic acid treatments compared to water-treated control and the water-treated fruits showed the lowest scores below the acceptability limit except for skin colour. In conclusion, our results suggest using methyl jasmonate and/or salicylic acid to enhance and prolong the storability of apricot fruits during both cold storage and shelf-life period

ACS Style

Ahmed Ezzat; Amin Ammar; Zoltán Szabó; József Nyéki; Imre J. Holb. Postharvest Treatments with Methyl Jasmonate and Salicylic Acid for Maintaining Physico-Chemical Characteristics and Sensory Quality Properties of Apricot Fruit during Cold Storage and Shelf-Life. Polish Journal of Food and Nutrition Sciences 2017, 67, 159 -166.

AMA Style

Ahmed Ezzat, Amin Ammar, Zoltán Szabó, József Nyéki, Imre J. Holb. Postharvest Treatments with Methyl Jasmonate and Salicylic Acid for Maintaining Physico-Chemical Characteristics and Sensory Quality Properties of Apricot Fruit during Cold Storage and Shelf-Life. Polish Journal of Food and Nutrition Sciences. 2017; 67 (2):159-166.

Chicago/Turabian Style

Ahmed Ezzat; Amin Ammar; Zoltán Szabó; József Nyéki; Imre J. Holb. 2017. "Postharvest Treatments with Methyl Jasmonate and Salicylic Acid for Maintaining Physico-Chemical Characteristics and Sensory Quality Properties of Apricot Fruit during Cold Storage and Shelf-Life." Polish Journal of Food and Nutrition Sciences 67, no. 2: 159-166.

Research article
Published: 01 September 2016 in Plant Disease
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In a 4-year study in a whole-field sanitized organic apple orchard, the effectiveness of nine fungicide treatments, including potassium mono- and bicarbonate and their combinations with wettable sulfur, were evaluated for scab and powdery mildew control on two cultivars with different susceptibility to scab and powdery mildew, under two pruning treatments. The whole-field sanitation practice was performed by removal of infected fallen leaves. Treatment effects on phytotoxicity and yield were also determined. Pruning significantly reduced leaf scab incidence but only on the more scab-susceptible Idared. Pruning significantly reduced mildew incidence in most years and on both cultivars but the more mildew-susceptible Jonathan showed significantly higher mildew incidence than Idared. Among products approved for organic production, the best scab control was achieved with a potassium mono- or bicarbonate treatment combined with wettable sulfur, except for Jonathan in 2011 on leaf and in 2014 on both leaf and fruit, and for Idared in 2013 on fruit. The best mildew control was also achieved with potassium mono- or bicarbonate treatments combined with wettable sulfur, with exceptions on shoots of Idared in 2011 and 2013 and on fruit of Idared in 2012. Leaf phytotoxicity was significantly higher in all potassium carbonate treatments compared with untreated plots, except for Idared in 2012, while fruit russet in these treatments did not differ significantly from the untreated plots. However, phytotoxicity values of all carbonate treatments were significantly lower than the lime sulfur treatment in most years on both cultivars. Yield of the potassium mono- or bicarbonate treatments combined with wettable sulfur was significantly higher than the untreated plots in the pruned treatments for both cultivars in all years. The integrated control approach designed for organic disease management against the two pathogens is discussed.

ACS Style

Imre J. Holb; Stefan Kunz. Integrated Control of Apple Scab and Powdery Mildew in an Organic Apple Orchard by Combining Potassium Carbonates with Wettable Sulfur, Pruning, and Cultivar Susceptibility. Plant Disease 2016, 100, 1894 -1905.

AMA Style

Imre J. Holb, Stefan Kunz. Integrated Control of Apple Scab and Powdery Mildew in an Organic Apple Orchard by Combining Potassium Carbonates with Wettable Sulfur, Pruning, and Cultivar Susceptibility. Plant Disease. 2016; 100 (9):1894-1905.

Chicago/Turabian Style

Imre J. Holb; Stefan Kunz. 2016. "Integrated Control of Apple Scab and Powdery Mildew in an Organic Apple Orchard by Combining Potassium Carbonates with Wettable Sulfur, Pruning, and Cultivar Susceptibility." Plant Disease 100, no. 9: 1894-1905.

Journal article
Published: 10 April 2016 in International Journal of Horticultural Science
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In a two-year Hungarian study, the temporal progress of brown rot incidence and various injury types were studiedin organic fruit orchards and the relationship between brown rot and injury types was determined. Results showed that brownrot reached an almost 20% incidence level in both years. Total injury incidence reached up to 5.3 and 19.8% in the two years.In all cases, insect injury incidence was the highest among injury types in most assessment dates. Incidence levels of otherinjury types (bird injury, mechanical injury and other injury) began to increase, but none of those reached levels >4%. Pearson’scorrelation coefficients showed that brown rot incidence correlated significantly with the incidence of insect injury. In addition,brown rot incidence and the incidence levels of bird injuries was also significantly correlated. High injury and brown rotincidence levels suggest further improvements on organic fruit protection.

ACS Style

Abonyi F.; Vámos A.; Lakatos P.; Rózsa A.; Holb I. J.. Fruit injury in organic fruit production and its relationship to brown rot caused by Monilinia spp. International Journal of Horticultural Science 2016, 22, 7 -9..

AMA Style

Abonyi F., Vámos A., Lakatos P., Rózsa A., Holb I. J.. Fruit injury in organic fruit production and its relationship to brown rot caused by Monilinia spp. International Journal of Horticultural Science. 2016; 22 (1-2.):7-9..

Chicago/Turabian Style

Abonyi F.; Vámos A.; Lakatos P.; Rózsa A.; Holb I. J.. 2016. "Fruit injury in organic fruit production and its relationship to brown rot caused by Monilinia spp." International Journal of Horticultural Science 22, no. 1-2.: 7-9..

Journal article
Published: 10 April 2016 in International Journal of Horticultural Science
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In this minreview, mechanical and physical control against apple fungal diseases among non-chemical control approaches weresummarized. This overview listed five groups of mechanical and physical control methods: pruning, removal of inoculum sources, shreddingof leaf litter, burying of inoculum sources and flaming of leaf litter. These methods were shown to reduce succesfully infection potentialof inoculum sources in orchards and these non-chemical control measures are one of the most essential approaches for preventative fungaldisease management. However, most of these methods are not widely spread in the apple-growing practice due to relatively low controlefficacy, medium to high labour costs and/or time limits during the season.

ACS Style

Holb I. J.. Mechanical and physical control in apple orchards as preventative fungal disease management. International Journal of Horticultural Science 2016, 22, 19 -21..

AMA Style

Holb I. J.. Mechanical and physical control in apple orchards as preventative fungal disease management. International Journal of Horticultural Science. 2016; 22 (1-2.):19-21..

Chicago/Turabian Style

Holb I. J.. 2016. "Mechanical and physical control in apple orchards as preventative fungal disease management." International Journal of Horticultural Science 22, no. 1-2.: 19-21..

Journal article
Published: 25 November 2015 in European Journal of Plant Pathology
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In a 6-year Hungarian study, ascospore density of Erysiphe necator in the air was monitored and related to three weather variables (temperature, relative humidity, and rainfall) and powdery mildew disease progress in two commercial vineyards. Temporal pattern in aerial density was also quantified. In total, 71 ascospore trapping periods were detected over the 6-year period from early April until end June. Across all years, 6.6 % of the total ascospores (0.5 % mean ascospore percent per day) were caught between the initiation of sampling in April and bud break, 62.2 % (1.6 %) from bud break to bloom, and 31.2 % (0.3 %) between bloom and the conclusion of sampling at the end of June. Hourly proportions of ascospores caught did not reveal diurnal patterns of spore release. All three weather factors (in the order of rainfall, relative humidity and temperature) correlated significantly with mean ascospore catches in each year. Mean hourly rainfall correlated best with mean hourly ascospore catches (correlation coefficient, r, ranged from 0.43 to 0.78) in both vineyards and in all years. First leaf and berry symptoms appeared between 7 and 24 May and between 25 May and 19 June, respectively, during the 6-year study. Disease started to progress slowly after the appearance of the first infected leaf followed by an exponential increase from early June. By the end of June, leaf and berry disease incidences ranged from 4.1 to 98.2 % and from 0.9 to 6.8 %, respectively, over the 6-year period. Leaf incidences showed significant relationship with corresponding cumulative numbers of trapped ascospore in five out of 6 years, which was described by three-parameter Gompertz functions in each year. Results were compared and discussed with previous observations.

ACS Style

Imre J. Holb; István Füzi. Monitoring of ascospore density of Erysiphe necator in the air in relation to weather factors and powdery mildew development. European Journal of Plant Pathology 2015, 144, 751 -762.

AMA Style

Imre J. Holb, István Füzi. Monitoring of ascospore density of Erysiphe necator in the air in relation to weather factors and powdery mildew development. European Journal of Plant Pathology. 2015; 144 (4):751-762.

Chicago/Turabian Style

Imre J. Holb; István Füzi. 2015. "Monitoring of ascospore density of Erysiphe necator in the air in relation to weather factors and powdery mildew development." European Journal of Plant Pathology 144, no. 4: 751-762.