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Jordan Journal of Agricultural Sciences, Volume 8, No.3 2012 Occurrence and Control of Strawberry Powdery Mildew in Al-Shoubak/ Jordan Muwaffaq Ramadan Karajeh1, Ziad Barakat Al-Rawashdeh2, and Ezz Al-Dein Muhammed Al-Ramamneh3 ABSTRACT Powdery mildew of strawberry caused by the fungus Sphaerotheca macularis f. sp. fragariae was found in AlShoubak area under glasshouse conditions. White superficial fungal growth was more abundant on the lower than the upper leaf surface and no cleistothecia were noticed on any plant parts. Top leaves were more susceptible than middle or bottom leaves. Strawberry cultivars Albion and Camarosa were artificially inoculated with the fungus under growth room conditions. Disease incidence and severity were 46.7% and 50.8% in cv. Albion and significantly different from that (1.6% and 5.2%, respectively) in cv. Camarosa. In vitro leaflet bioassays and a runner-tip plantlet experiment were done to assess the influence of some fungicides and resistance-inducing chemicals in controlling the disease. Canvil was significantly effective in controlling the disease while sulfur, Triadimefon, Mycozim and Punch were only effective at the high application rates. Both calcium chloride at 1 g/l and hydrogen peroxide at 10 mM were effective in controlling powdery mildew on strawberry. Keywords: Cultivars, fungicides, management, Sphaerotheca. INTRODUCTION or glass-house) conditions in irrigated agricultural areas The total area of greenhouses was estimated about including Jordan Valley, uplands (e.g. Al-Shoubak) and 40,700 hectares worldwide (Witter and Castilla, 1995). desert plains with a total annual production of about 175 The greenhouse industry as a whole represents a tons in 2008 according to Jordan exports and producers minuscule part of the total agricultural production, but association for fruit and vegetables (JEPA). the gross return to the economy could be significant Powdery mildew of strawberry caused by the fungus (Takeda, 2000). Strawberry (Fragaria X ananassa Sphaerotheca macularis (Wallr. Ex Fr.) Jacz. f. sp. Duchesne) production has increasingly been transferred fragariae Peries, is a major disease of this crop from the fields into covered systems. In Jordan, worldwide (Spencer, 1978; Maas, 1998). The fungus strawberry is mainly planted under greenhouse (plastic attacks above-ground plant parts causing serious damage to 1 Associate Professor of Plant Pathology, Department of Plant Protection & IPM, Faculty of Agriculture, Mu’tah University, Karak 7, Jordan. 2 Assistant Professor of Plant Protection, Al-Shoubak College, Al-Balqa' Applied University, Al-Shoubak 71911, Jordan 3 Assistant Professor of Horticulture, Al-Shoubak College, Al-Balqa' Applied University, Al-Shoubak 71911, Jordan Received on 17/5/2011 and Accepted for Publication on 30/4/2012. the foliage and resulting in reduction of photosynthesis due to dense mycelial coverage of leaf surface, which can lead to necrosis and eventual defoliation (Maas, 1998). Powdery mildew causes economic losses in the marketable fruit yield (Horn et al., 1972; Spencer, 1978). Development of powdery mildew depends on optimum temperature (15–25 °C) and high relative -380- © 2012 DAR Publishers/University of Jordan. All Rights Reserved. Jordan Journal of Agricultural Sciences, Volume 8, No.3 2012 humidity, higher than 75 %, but less than 98 % spraying, etc. The day temperature was ranged between (Amsalem et al., 2006). Mycelia develop, survive in 15-25°C, while the night temperature during cool nights green tissue under all condition and sporulate under 5– was 30 °C (Miller et al., 2003). temperature was approximately 14°C and 16°C during Prevention is the best method of powdery mildew between 8-15°C. The mean daily outside the 2008 and 2009 strawberry growing seasons, control of strawberry through avoiding the use of respectively. susceptible cultivars and through following up good Pathogen identification and inoculum preparation cultural practices. However, susceptible strawberries may require protection with foliar sprays with fungicides The powdery mildew population of Sphaerotheca to reduce infection and consequently fruit yield losses macularis f. sp. fragariae used in the inoculations (Okayama, 1995; Ashour, 2009). Use of induced originated from strawberries cv. Albion previously resistance in disease management has a promising grown in the same glasshouse. The fungus was identified approach against several bacterial, fungal, and viral plant under a slide stereoscopic microscope based on the diseases during the past decade as the application of morphology of conidia. Conidia are smooth-walled and certain environmentally safe chemicals (e.g. calcium barrel-shaped, 25 to 38 µm long and 15 to 23 µm wide chloride or hydrogen peroxide) may activate the (Braun et al., 2002). The fungus was maintained on endogenous defense mechanisms of plants, providing young susceptible plants of the same cultivar. long-lasting resistance. Resistance-inducing chemicals Sporulating colonies of powdery mildew on leaves were investigated as safe alternatives for controlling were put into a plastic Petri dish containing distilled powdery mildews on cucurbits and strawberry (Abo- water. Conidia were detached by brushing. The Taleb, 2000; Hilall, 2004; Palmer, 2007; Hukkanen et concentration of the fungal inoculum was adjusted to 107 al., 2007; Abada et al., 2008; Ashour, 2009). conidia/ ml using a haemocytometer slide (Rodriguez- Therefore, this research was conducted to study the Tudela et al., 2003). The pathogenicity of the fungus occurrence and control of strawberry powdery mildew was confirmed by spraying the conidial suspension at 10 under glasshouse conditions in Al-Shoubak area of strawberry plants (cv. Albion) under controlled growth Jordan. chamber conditions (20 ± 2°C and 12 hour-day light). MATERIALS AND METHODS Early foliar infections of Sphaerotheca macularis f. sp. Greenhouse facilities and plant material fragariae were characterized by small white patches of Visual observations of strawberry powdery mildew superficial growths of the fungus on leaf blade and were carried out inside a commercial glasshouse at Al- petiole and small fruits of the susceptible plants of cv. Shoubak area of Jordan, situated approximately 260 km Albion, dense mycelial growth and numerous chains of south of Amman. The greenhouse had several passages conidia give these patches a powdery appearance. 2 between planting lines and 100 m long polystyrene Artificial inoculation under growth room conditions shelves on each side of the greenhouse. Each shelf contained 400 strawberry (cv. Albion) plants in peat Ten plants of strawberry cv. Camarosa or cv. Albion bags in a single row. The height of the shelves above the transplanted into pots containing a pasteurized mixture floor could be adjusted whenever necessary for picking, of clay, peat and perlite (1:1:1 v/v/v) were individually -381- Occurrence and Control of… Muwaffaq Ramadan Karajeh et al sprayed with the conidial suspension at 107 conidia/ ml bioassay, leaflets (5cm-in-diameter) were individually concentration. All plants were allowed to grow under picked from strawberry (cv. Albion) plants and dipped in growth room conditions with a 12 hour photoperiod 100 ml of the tested chemical solutions of each fungicide under fluorescent light (4000 lux /day) for four weeks. (Table 1) at the highest and lowest application rates Spreader powdery mildew-heavily diseased plants were according to manufacturer's instructions or resistance distributed among the artificially inoculated plants to inducer (hydrogen peroxide at 10 and 100mM or calcium increase the possibility of infection. Disease severity was chloride at 1 and 10 g/l) or distilled water as a control for categorized using 0-4 disease scale (0: no infection, 1: 10 seconds and then sprayed with the conidial suspension. small patch (up to 10%), 2: 11-25%, 3: 26-50% and 4: Each leaflet was placed into a test tube containing 10 ml more than 50 % leaf area covered with mildew growth) distilled water and incubated in a full-controlled growth as described by Okayama et al. (1995). The overall chamber at 20°C with a 12 hour photoperiod under disease severity % was the sum of numerical ratings per fluorescent light (3000 lux /day) for one week. All a treatment divided on the total number of leaves treatments and control were arranged in a completely observed multiplied 100 over the maximum disease randomized design (CRD). Each treatment was replicated category value (4). Disease incidence was expressed as three times. Disease severity was rated from 0 to 100% the % of diseased leaflets per a plant. according to mycelial coverage of infected leaves and was In vitro leaf discs bioassay recorded one week after treatment. Two in vitro leaflet bioassays were done, in the first Table 1. Detailed information of fungicides used in this study: Fungicide Flusilazole Hexaconazole Triadimefon Carbendazim Sulfur Trade name Punch Canvil Triadimefon Mycozim H-Sulfur Formulation 40% EC 5% SC 20% EC 50% SC 80% WP Company Dupont Vapco Singma Taicang city Al-Lahab Chemical group Triazoles Triazoles Triazoles Benzimidizoles Minerals While in the second bioassay, powdery mildew- treatment compared with that of the control. If the % of infected leaflets (5cm-in-diameter) were individually disease control more than 50% the treatment is picked from strawberry (cv. Albion) plants, dipped in considered effective in controlling the powdery mildew. 100 ml of the tested chemical solutions or distilled water Runner-tip plantlets experiment as a control for 10 seconds, placed into a test tube Runner-tip plantlets slightly infected with powdery containing cotton plug moistened with distilled water mildew (around 30% disease severity) were individually and incubated as before. Treatments and control were picked from strawberry (cv. Albion) plants, transplanted replicated three times and arranged in CRD. Disease into small plastic pots (250ml in volume) filled with severity % was assessed and recorded as before. The moistened perlite and sprayed with the tested chemical percentage of disease control was also recorded as the % solutions or distilled water as a control and incubated in of relative reduction in the disease severity % of the a plant growth chamber at 20°C with a 12 hour -382- Jordan Journal of Agricultural Sciences, Volume 8, No.3 2012 photoperiod under fluorescent light (3000 lux /day) and were noticed on the patches on the leaves, fruits or other 80% relative humidity for one week. Disease severity % plant parts under field, greenhouse or laboratory was assessed as previously described while disease conditions. Regarding to leaf position on strawberry plant, there incidence was expressed as the % of diseased leaflets per were no significant differences in disease severity % a plantlet. Statistical analysis between top, middle or bottom leaves during 2008 in Data were analyzed statistically using general linear strawberry growing season under glasshouse conditions model (GLM) procedure (SPSS software version 11.5; while top leaves were more susceptible for powdery SPSS Inc., Chicago, USA). Least significance difference mildew infection during 2009 strawberry growing (LSD) test and t-test were used for mean separation at season (Figure 1). The edges of heavily infected leaves the 0.05 probability level (Steel et al., 1997). curled upward. Disease incidence and severity RESULTS percentages were 46.7% and 50.8%, respectively on cv. More patches were found on the lower surface than Albion and significantly different from that (1.6% and 5.2%, respectively) on cv. Camarosa (Table 2). the upper leaf surface. Few patches of the mycelial growth were noticed on cv. Camarosa. No cleistothecia Table 2. Disease incidence and severity of powdery mildew on two strawberry cultivars under growth room conditions. Cultivar Disease incidence % Disease severity % Albion 46.71 a2 50.8 a 1.6 b 5.2 b Camarosa 2 Average of 10 plants/ treatment Means within columns followed by the same letters are not significantly different at 0.05 probability level using t-test. A- Strawberry growing season 2008 100 Disease severity % 1 80 top 60 middle 40 bottom 20 0 8 Mr 16 Mr 4 Ap 22 Ap 10 Ma Date of disease assessment -383- 28 Ma Occurrence and Control of… Muwaffaq Ramadan Karajeh et al B- Strawberry growing season 2009 Disease severity % 100 80 top 60 middle 40 bottom 20 0 8 Mr 16 Mr 4 Ap 26 Ap 9 Ma 28 Ma Date of disease assessment Figure 1. Powdery mildew disease development on strawberry with respect to leaf position (top, middle and bottom) during 2008 (LSD0.05= 10.5) and 2009 (LSD0.05= 22.4) growing seasons inside glass-house in Al-Shoubak area of Jordan. Table 3 shows the results of the two in vitro leaflet (50% Carbendazim) and sulfur gave good control at their bioassays. Among the tested fungicides, Canvil (5% high application rates (77 and 58%, respectively). At hexaconazole) at both low and high application rates their low concentrations, both hydrogen peroxide (10 gave significant reductions in disease severity % mM) and calcium chloride (1 g/l) as resistance inducers compared to that of the control (water) and lead to more gave 61 and 68% control, respectively. than 50% control (58 and 64%, respectively). Mycozim Table 3. Effect of fungicides and resistance-inducing chemicals on powdery mildew disease severity on strawberry (cv. Albion) leaflets in two in vitro leaflet bioassays: Fungicide/ resistance inducer Canvil Triadimefon Punch Mycozim Sulfur Conc. DS1 %1 DS2 %2 Mean Control %3 Low, 4ml/ 20L 11.74 c5 38.8 b 25.4 h 58 High, 8ml/ 20L 18.3 c 25.0 bc 21.8 j 64 Low, 4ml/ 20L 52.5 a 44.3 ab 48.6 c 20 High, 10ml/ 20L 13.8 c 62.3 ab 38.2 e 37 Low, 1ml/ 20L 44.4 ab 44.1 ab 44.4 d 27 High, 1.5ml/ 20L 56.8 a 44.5 ab 50.8 b 17 Low, 10 ml/20L 8.3 c 56.5 ab 32.6 f 47 High, 20 ml/20L 20.0 bc 7.7 c 14.0 l 77 Low, 40g/ 20L 10.1 c 67.0 a 38.7 e 37 High, 50g/ 20L 10.0 c 40.6 b 25.5 h 58 -384- Jordan Journal of Agricultural Sciences, Volume 8, No.3 2012 Conc. DS1 %1 DS2 %2 Mean Control %3 Low, 1 g/L 7.5 c 31.0 bc 19.4 k 68 High, 10 g/L 18.4 c 43.8 ab 31.3 g 49 Low, 10mM 10.5 c 36.5 b 23.7 i 61 High, 100mM 51.3 a 46.5 ab 49.1 c 20 - 56.7 a 65.0 ab 61.0 a - Fungicide/ resistance inducer Calcium Chloride Hydrogen peroxide Water 1 DS1%: disease severity % in the first assay recorded 1 week after treatment. DS2%: disease severity % in the second assay recorded 1 week after treatment. 3 Control % = Powdery mildew disease severity% in control- that in treatment divided on disease severity in the control (water) multiplied by 100%. 4 Average of 3 replicates. 5 Means within columns followed by the same letters are not significantly different at 0.05 probability level using LSD test. 2 Results of the runner-tip plantlet experiment sulfur at their low application rates. Hydrogen peroxide indicated that the % of disease leaflets and disease at both concentrations (10 and 100 mM) gave 56 and severity % were significantly reduced for the treatments 66% control, respectively while calcium chloride gave than that for the control (Table 4). All of the tested the highest % of control (79%) at 1 g/l concentration fungicides and resistance inducers gave more than 50% (Table 4). control except for Triadimefon, Punch, Mycozim and Table 4. Effect of fungicides and resistance-inducing chemicals on powdery mildew disease development on strawberry (cv. Albion) runner-tip plantlets: Fungicide/ resistance inducer Canvil 5%SC Triadimefon Punch 40EC Mycozim Sulfur Calcium Chloride Hydrogen peroxide Conc. LD %1 DS %2 Control %3 Low, 4ml/ 20L 33.34 c5 25.6 c-f 63 High, 8ml/ 20L 33.3 c 28.8 b-f 59 Low, 4ml/ 20L 33.3 c 36.6 bcd 48 High, 10ml/ 20L 33.3 c 18.6 ef 73 Low, 1ml/ 20L 33.3 c 37.0 bcd 47 High, 1.5ml/ 20L 33.3 c 18.0 ef 74 Low, 10 ml/ 20L 33.3 c 36.2 b-e 48 High, 20 ml/20L 33.3 c 19.0 ef 83 Low, 40g/ 20L 50 b 46.0 b 34 High, 50g/ 20L 50 b 14.5 f 79 Low, 1 g/L 33.3 c 15.0 f 79 High, 10 g/L 33.3 c 36.5 b-e 48 Low, 10mM 50 b 20.5 ef 71 -385- Occurrence and Control of… Muwaffaq Ramadan Karajeh et al Conc. LD %1 DS %2 Control %3 High, 100mM 33.3 c 30.5 b-f 56 - 66.7 a 69.8 a - Fungicide/ resistance inducer Water 1 LD%: % of diseased leaflets per a plantlet. DS%: disease severity %. 3 Control % = Powdery mildew disease severity% in control- that in treatment divided on disease severity in the control (water) multiplied by 100%. 4 Average of 3 replicates. 5 Means within columns followed by the same letters are not significantly different at 0.05 probability level using LSD test. 2 DISCUSSION time of ripening and liberation of ascospores is Powdery mildew of strawberry was found in Al- important to development of integrated control of Shoubak area of Jordan under glasshouse conditions. powdery mildew (Jarmolica and Bankina, 2009). In our The fungus Sphaerotheca macularis f. sp. fragariae was study, no cleistothecia were found. It seems that the the causal agent of the disease and its pathogenicity was fungus does not form cleistothecia under glasshouse and confirmed by inoculation on the susceptible strawberry laboratory cv. Albion under laboratory conditions. To our powdery mildew were detected in Latvia (Jarmolica and knowledge, this is the first study done on strawberry Bankina, 2009) and Norway (Gadoury et al., 2007) powdery mildew caused by Sphaerotheca macularis f. while no cleistotheica were detected in England (Peries, sp. fragariae of in Jordan. 1962) and Spain (Santos et al., 2002). Presence or conditions. Cleistothecia of strawberry Regarding to plant leaf position, top leaves were absence of cleistothecia as a source of genetic found more susceptible than middle or bottom leaves for variability, may affect the efficiency of applied powdery mildew infection. Lower leaf surface was more fungicides through developing resistance. Benomyl susceptible for powdery mildew infection than the upper failed to control powdery mildew on strawberry plants in leaf surface. At least in part, the more-common Maine appearance of the pathogen on the lower leaf surface Sphaerotheca macularis f. sp. fragariae were discovered reflects escape of the upper epidermis from infection due while in other US states (North Carolina, Tennessee and to leaf folding during a critical susceptible phase Arkansas) where no cleistothecia were found, benomyl (Gadoury et al., 2007). Leaf and plant phenology can successfully controlled the disease (Howard and also be an important factor affecting tolerance. Higher Albregts, 1982). and Michigan where cleistothecia of disease incidence on younger (top) leaves was noticed. Strawberry cv. Camarosa was more resistant to This agrees with Okayama et al. (1995), who observed powdery mildew infection than cv. Albion. In a previous that the youngest leaflets were more susceptible than the study (Mertely et al., 2004) to evaluate the effect of intermediate or the oldest leaflets and stolon-derived powdery mildew on cv. Camarosa inside tunnels, daughter plants were more susceptible to infection than powdery mildew symptoms on plant foliage were light mature plants. and apparently unrelated to marketable yield. Therefore, the more resistant cv. Camarosa could be effectively The main source of infection is cleistothecia, and -386- Jordan Journal of Agricultural Sciences, Volume 8, No.3 2012 conditions (Ashour, 2009). used to control powdery mildew. Among the tested chemical fungicides, Canvil gave a Hydrogen peroxide at 10 mM was effective in considerable control for powdery mildew. Other controlling powdery mildew on strawberry. After a foliar fungicides (Sulfur, Triadimefon, Mycozim and Punch spray with a solution of hydrogen peroxide, leaves (40% flusilazole) were more effective at the high exhibited resistant against Podosphaera fusca (Fr.) U. application rates. Fungicides should be applied at the Braun & Shishkoff fungus, the causal agent of cucumber first sign of disease to control powdery mildew on powdery mildew. Hydrogen peroxide (at 15 mM susceptible cultivars. This is especially important when concentration) was able to greatly decrease the disease using protectant contact fungicides such as sulfur. The severity in two subsequent cucumber growing seasons control (Hafez et al., 2008). of powdery mildew with fungicides is problematic since only a limited number of appropriate Resistance to downy mildew caused by Sclerospora systemic fungicides, is available and powdery mildew graminicola on pearl millet was chemically induced by fungi have a high tendency of developing fungicide- treating seeds of highly susceptible cultivars with the tolerant strains as observed with other crops (Chin et al., resistance activator benzothiadiazole (BTH), calcium 2001; McGrath, 2001). chloride and hydrogen peroxide giving 78%, 66% and Foliar application of nutrients can reduce severity of 59% protection, respectively (Geetha and Shetty, 2002). fungal diseases by supplementing the nutrition of the Spraying barley leaves with 25 mM of hydrogen plant, increasing natural foliar defence mechanisms and peroxide inhibited powdery mildew pathogen (Blumeria in graminis f. sp. hordei) and symptom development some cases adversely affecting the fungal (Hafez and Kiraly, 2003). development (Palmer, 2007). Calcium appears to have primary role in plant defence through maintenance of In a conclusion, the powdery mildew of strawberry membranes and cell walls (Marschner, 1995) by can be managed effectively by the use of resistant enhancing the cell wall rigidity (Graham, 1983; Datnoff cultivar e.g. Camarosa and protective or curative foliar et al., 2001). sprays with effective fungicides or resistance-inducing Calcium chloride was effective at 1 g/l. This agrees chemicals. Further studies are needed to compare the with Palmer (2007) who found that calcium chloride influence of resistance-inducing chemicals with that of foliar sprays were beneficial in controlling powdery fungicides on strawberry under greenhouse and field mildew on strawberry. Spraying of calcium chloride conditions of Jordan. caused significant decrement in the disease severity with ACKNOWLEDGEMENTS significant increment in the fruit yield when compared This work was financially funded in part by the Academic Research Deanship, Mutah University, Jordan. with check treatments under glasshouse and field REFERENCES Abada K. A., R. Mervat and S. H. Mostafa. 2008. Induced Abo-Taleb M. A. 2000. Biochemical changes associated with resistance against powdery mildew in cucumber. Journal of application of some resistance inducing compounds for Biological and Chemical Environmental Sciences. 3: 45-56. controlling powdery mildew of cucumber. Egyptian Journal -387- Occurrence and Control of… Muwaffaq Ramadan Karajeh et al of Applied Science. 16: 387-404. symptom expression of barley susceptible and resistant to powdery mildew. Acta Phytopath. Entomol. Hung. 38: Amsalem L., Freeman S., D. Rav-David, Y. Nitzani, A. 227–236. Sztejnberg, I. Pertot, and Y. Elad. 2006. 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(fragariaeﻓﻲ ﻤﻨﻁﻘﺔ ﺍﻟﺸﻭﺒﻙ ﺘﺤﺕ ﻅﺭﻭﻑ ﺍﻟﺒﻴﺕ ﺍﻟﺯﺠﺎﺠﻲ؛ ﺤﻴﺙ ﻅﻬﺭ ﻨﻤﻭ ﺍﻟﻔﻁﺭ ﺍﻷﺒﻴﺽ ﺒﻜﺜﺎﻓﺔ ﻋﻠـﻰ ﺍﻷﺴـﻁﺢ ﺍﻟﺴﻔﻠﻴﺔ ﻟﻸﻭﺭﺍﻕ ،ﻭﻟﻡ ﺘﻅﻬﺭ ﺍﻷﺠﺴﺎﻡ ﺍﻟﺜﻤﺭﻴﺔ ﺍﻟﻤﻐﻠﻘﺔ ﺍﻟـ cleistotheciaﻋﻠﻰ ﺃﻱ ﺠﺯﺀ ﻨﺒﺎﺘﻲ ﻤﻁﻠﻘﺎﹰ ،ﻭﻜﺎﻨﺕ ﺍﻷﻭﺭﺍﻕ ﺍﻟﻌﻠﻭﻴﺔ ﺃﻜﺜﺭ ﻋﺭﻀ ﹰﺔ ﻟﻺﺼﺎﺒﺔ ﻤﻥ ﺍﻷﻭﺭﺍﻕ ﺍﻟﻭﺴﻁﻰ ﻭﺍﻟﺴﻔﻠﻴﺔ .ﺘﻡ ﺇﺠﺭﺍﺀ ﻋﺩﻭﻯ ﺍﺼﻁﻨﺎﻋﻴﺔ ﻟﺼﻨﻔﻲ ﺍﻟﻔﺭﺍﻭﻟـﺔ ﺍﻟﺒﻴـﻭﻥ ﻭﻜﻤﺎﺭﻭﺯﺍ ﺘﺤﺕ ﻅﺭﻭﻑ ﻏﺭﻓﺔ ﺍﻟﻨﻤﻭ؛ ﺤﻴﺙ ﻜﺎﻨﺕ ﺸﺩﺓ ﺍﻟﻤﺭﺽ ﻭﻨﺴﺒﺔ ﺤﺩﻭﺜﻪ %46.7ﻭ %50.8ﻓﻲ ﺼـﻨﻑ ﺍﻟﺒﻴـﻭﻥ، ﻭﻫﻲ ﺃﻋﻠﻰ ﻤﻌﻨﻭﻴﹰﺎ ﻤﻥ ﺍﻟﺼﻨﻑ ﻜﻤﺎﺭﻭﺯﺍ ) %1.6ﻭ %5.2ﻋﻠﻰ ﺍﻟﺘﻭﺍﻟﻲ( .ﺘﻡ ﺇﺠﺭﺍﺀ ﻓﺤﺹ ﻤﺨﺒﺭﻱ ﺒﺎﺴﺘﺨﺩﺍﻡ ﻭﺭﻴﻘـﺎﺕ ﺍﻟﻔﺭﺍﻭﻟﺔ ﻟﺩﺭﺍﺴﺔ ﺘﺄﺜﻴﺭ ﺒﻌﺽ ﺍﻟﻤﺒﻴﺩﺍﺕ ﺍﻟﻔﻁﺭﻴﺔ ﻭﺍﻟﻜﻴﻤﺎﻭﻴﺎﺕ ﺍﻟﻤﺤﻔﺯﺓ ﻟﻠﻤﻘﺎﻭﻤﺔ ﻓﻲ ﻤﻜﺎﻓﺤﺔ ﺍﻟﻤﺭﺽ؛ ﺤﻴﺙ ﺘﻔﻭﻕ ﻤﻌﻨﻭﻴـﹰﺎ ﻻ ﻋﻨﺩ ﻨـﺴﺒﺔ ﺍﻻﺴـﺘﺨﺩﺍﻡ ﻤﺒﻴﺩ ﻜﺎﻨﻔل ﻓﻲ ﻤﻜﺎﻓﺤﺔ ﺍﻟﻤﺭﺽ ﺒﻴﻨﻤﺎ ﻜﺎﻥ ﻜل ﻤﻥ ﺍﻟﻜﺒﺭﻴﺕ ﻭﺘﺭﺍﻴﺩﻴﻤﻔﻭﻥ ﻭﻤﺎﻴﻜﻭﺯﻴﻡ ﻭﺒﻨﺵ ﻓﻌﺎ ﹰ ﻻ ل ﻤﻥ ﻜﻠﻭﺭﻴﺩ ﺍﻟﻜﺎﻟﺴﻴﻭﻡ )ﻋﻨﺩ 1ﻏﻡ /ﻟﺘﺭ( ﻭﺒﻴﺭﻭﻜﺴﻴﺩ ﺍﻟﻬﻴﺩﺭﻭﺠﻴﻥ )ﻋﻨﺩ 10ﻤﻠﻴﻤﻭﻟﺭ( ﻓﻌﺎ ﹰ ﺍﻟﻌﻠﻴﺎ ﻓﻘﻁ ،ﻭﻜﺎﻥ ﺍﺴﺘﺨﺩﺍﻡ ﻜ ّ ﻓﻲ ﻤﻜﺎﻓﺤﺔ ﺍﻟﺒﻴﺎﺽ ﺍﻟﺩﻗﻴﻘﻲ ﻋﻠﻰ ﺍﻟﻔﺭﺍﻭﻟﺔ. ﺍﻟﻜﻠﻤﺎﺕ ﺍﻟﺩﺍﻟﺔ :ﺃﺼﻨﺎﻑ ،ﻤﺒﻴﺩﺍﺕ ﻓﻁﺭﻴﺔ ،ﺇﺩﺍﺭﺓ.Sphaerotheca ، ____________________________________________ (1 ﺃﺴﺘﺎﺫ ﻤﺸﺎﺭﻙ ﻓﻲ ﺃﻤﺭﺍﺽ ﺍﻟﻨﺒﺎﺕ ،ﻗﺴﻡ ﻭﻗﺎﻴﺔ ﺍﻟﻨﺒﺎﺕ ﻭﺍﻟﻤﻜﺎﻓﺤﺔ ﺍﻟﻤﺘﻜﺎﻤﻠﺔ-ﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ ،ﺠﺎﻤﻌﺔ ﻤﺅﺘﺔ ،ﺍﻟﻜﺭﻙ ،7ﺍﻷﺭﺩﻥ (2ﺃﺴﺘﺎﺫ ﻤﺴﺎﻋﺩ ﻓﻲ ﻭﻗﺎﻴﺔ ﺍﻟﻨﺒﺎﺕ ،ﻜﻠﻴﺔ ﺍﻟﺸﻭﺒﻙ ،ﺠﺎﻤﻌﺔ ﺍﻟﺒﻠﻘﺎﺀ ﺍﻟﺘﻁﺒﻴﻘﻴﺔ ،ﺍﻟﺸﻭﺒﻙ ،71911ﺍﻷﺭﺩﻥ (3 ﺃﺴﺘﺎﺫ ﻤﺴﺎﻋﺩ ﻓﻲ ﺍﻟﺒﺴﺘﻨﺔ ،ﻜﻠﻴﺔ ﺍﻟﺸﻭﺒﻙ ،ﺠﺎﻤﻌﺔ ﺍﻟﺒﻠﻘﺎﺀ ﺍﻟﺘﻁﺒﻴﻘﻴﺔ ،ﺍﻟﺸﻭﺒﻙ ،71911ﺍﻷﺭﺩﻥ ﺘﺎﺭﻴﺦ ﺍﺴﺘﻼﻡ ﺍﻟﺒﺤﺙ 2011/5/17ﻭﺘﺎﺭﻴﺦ ﻗﺒﻭﻟﻪ .2012/4/30 -390-