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Öğe Characterization and pathogenicity of pythium-like species associated with root and collar rot of kiwifruit in Turkey(American Phytopathological Society, 2022) Türkkan, Muharrem; Özer, Göksel; Karaca, Gürsel; Erper, İsmail; Derviş, SibelDuring the period of June to October in 2018, a widespread decline was observed on kiwifruit vines in the vineyards located in the Altinordu, Fatsa, and Persembe districts of Ordu province in Turkey. The symptoms were associated with reddish-brown rots expanding from the root to the collar with sparse off-color foliage. Based on the percentage of the total infected samples across 18 vineyards, the most common oomycete species were Globisporangium intermedium (37.1%), Phytopythium vexans (34.3%), Globisporangium sylvaticum (14.3%), Globisporangium heterothallicum (11.4%), and Pythium dissotocum (2.9%). The morphological identification of isolates was confirmed based on partial DNA sequences containing the nuclear rDNA internal transcribed spacer region gene and the mitochondrial cytochrome c oxidase subunit II gene. The optimum growth temperature and the optimum pH values of the five species ranged from 22.98 to 28.25 degrees C and 5.67 to 8.51, respectively. Pathogenicity tests on the seedlings of kiwifruit cv. Hayward revealed significant differences in virulence among isolates. Phytopythium vexans and Globisporangium sylvaticum isolates caused severe root and collar rot resulting in seedling death, while Globisporangium heterothallicum and Globisporangium intermedium isolates had relatively lower virulence. All Globisporangium spp. and Phytopythium vexans isolates significantly decreased plant growth parameters (plant height, shoot and root dry weights, and root length); however, Pythium dissotocum caused very mild symptoms and did not affect these parameters of growth. To our knowledge, this is the first study reporting Globisporangium sylvaticum, Globisporangium heterothallicum, and Globisporangium intermedium causing root and collar rot on kiwifruit not only in Turkey but also in the world.Öğe First report of botrytis blight of tulip caused by Botrytis tulipae in Turkey(Springer, 2019) Erper, İsmail; Deligöz, İlyas; Özer, Göksel; Yıldırım, Elif; Türkkan, MuharremTulip (Tulipa L.) is one of the most important flower bulb crops with production of approximately forty-five million units as cut flowers in Turkey (Anonymous 2018). In 2018, some plants showed disease symptoms consisting of water-soaked spots on petals and leaves in tulip nurseries in Samsun province. . Infected plant tissues were cut into small pieces, placed on Tulip Leaf Agar medium after surface sterilization, and incubated at 18 °C for five days.Öğe First report of charcoal rot caused by Macrophomina phaseolina on kiwifruit in Turkey(Springer, 2020) Türkkan, Muharrem; Benli, Halil İbrahim; Yılmaz, Özkan; Özer, Göksel; Yaman, Mehmet; Şahin, Nusret; Erper, İsmailDuring June and August in 2018, kiwifruit (cv. Hayward) plants exhibiting symptoms of charcoal rot including chlorosis, necrosis, leaf shedding, root rot, and trunk dry rot were observed with an incidence of up 5% in three commercial orchards located in Altınordu, Fatsa and Perşembe districts of Ordu province. After surface sterilization with 1% NaClO, small pieces excised from root tissues of diseased plants were rinsed twice in sterile distilled water, dried on sterile filter papers and aseptically transferred to plates containing potato dextrose agar.Öğe First report of dactylonectria torresensis causing black root rot of strawberries in Kyrgyzstan(Springer, 2020) Erper, İsmail; Özer, Göksel; Alkan, Mehtap; Zholdoshbekova, Sezim; Türkkan, MuharremKyrgyzstan produces 2331 tons of strawberries annually at 427 ha (FAOSTAT 2020). In June 2019, strawberry plants showed some aboveground symptoms including stunting, lack of vigor, smaller fruit size, and leaf chlorosis with the incidence of 5% in the fields in Bishkek, Kyrgyzstan (Latitude: 42°83′44“N, Longitude: 74°57’42”E). The root systems of plants were smaller than healthy ones, and their feeder and main roots were mostly destroyed and showed sunken and necrotic black lesions.Öğe First report of damping-off on melon seedlings caused by Rhizoctonia solani AG 4 HG-II in Kyrgyzstan(Springer, 2022) Erper, İsmail; Göçmen, Münevver; Yıldırım, Elif; Türkkan, Muharrem; Alkan, Mehtap; Özer, GökselMelon (Cucumis melo L., Cucurbitaceae) is one of the most popular horticultural fruit crops in Kyrgyzstan. In May 2020, damping-off and stunted melon seedlings were observed in 2 fields in the Lenin District of Bishkek, Kyrgyzstan, with a 6% incidence. Isolation was performed from lesions of roots and hypocotyls of diseased seedlings on potato dextrose agar (PDA) acidified with 0.1% lactic acid.Öğe First report of dry rot of potato caused by Fusarium sambucinum in Kyrgyzstan(Springer Heidelberg, 2022) Erper, İsmail; Alkan, Mehtap; Zholdoshbekova, Sezim; Türkkan, Muharrem; Yıldırım, Elif; Özer, GökselIn October 2020, the presence of an intense Fusarium dry rot disease was detected during a survey of potato tubers in the production storage facilities in Chui region, Kyrgyzstan. The species of Fusarium isolates, obtained from infected tubers, were identified as Fusarium sambucinum by using morphological features and phylogenetic analyses of the transcription elongation factor 1-alpha (EF1-alpha) gene. The isolates were pathogenic to potato tubers, and Koch's postulates were confirmed by successful re-isolation of the pathogen. To our knowledge, this is the first report of dry rot of potato caused by Fusarium sambucinum in Kyrgyzstan.Öğe First report of garden cucumber root rot caused by Globisporangium ultimum var. ultimum in Kyrgyzstan(Springer, 2020) Erper, İsmail; Özer, Göksel; Zholdoshbekova, Sezim; Türkkan, MuharremGarden cucumber (Cucumis sativus L.) has been commonly cultivated in a wide area in Kyrgyzstan. In 2019, wilting and yellowing symptoms were observed on cucumber plants in three fields planted in Lenin district, Bishkek, Kyrgyzstan, with a general incidence of 6%. Diseased plants showing root rot symptoms were subjected to pathogen isolation. Infected tissues were superficially disinfected in 1% NaOCl for 1 min and placed to Petri dishes containing water agar (agar 15 g/l) amended with 0.1 g/l streptomycin sulfate.Öğe First report of Penicillium expansum causing postharvest fruit rot on pear in Kyrgyzstan(Springer, 2023) Erper, İsmail; Zholdoshbekova, Sezim; Alkan, Mehtap; Türkkan, Muharrem; Özer, GökselIn April 2022, symptoms of blue mould were observed on about 3% of pear (Pyrus communis L.) fruits at commercial markets in Bishkek, Kyrgyzstan. Fruits exhibited circular, light brown, watery lesions in several parts of the skin with masses of blue-green sporulation. Fungal isolations from ten fruits were performed on potato dextrose agar (PDA).Öğe First report of powdery mildew caused by Erysiphe elevata on Catalpa bignonioides in Turkey(Springer, 2019) Erper, İsmail; Özer, Göksel; Kalkan, Çağlar; Türkkan, MuharremCatalpa bignonioides is planted as a shade tree in Turkey. In autumn 2017, typical powdery mildew signs on leaves of C. bignonioides were observed on the main campus (Kurupelit) of Ondokuz Mayis University (OMU) in Samsun, Turkey.Öğe First report of Rhizoctonia solani AG 1-IB causing root and stem rot of kale (Brassica oleracea var. acephala) in Turkey(Springer, 2021) Benli, Halil İbrahim; Türkkan, Muharrem; Özer, Göksel; Erper, İsmailKale (Brassica oleracea L. var. acephala) has been commonly cultivated in the Ordu province, which is located in Turkey’s Middle Black Sea Region. In a survey carried out in Çaybaşı district of the province in 2018, symptoms of damping-of and stem rot were observed in approximately 7% of the plants in only one of the 10 commercial felds examined. Infected plant tissues were superfcially disinfected for 1 min in 1% NaOCl and transferred to Petri dishes containing Potato Dextrose Agar (PDA) amended with streptomycin sulfateÖğe First report of Rhizoctonia solani AG 4 HG-I causing damping off and wirestem of white cabbage in Turkey(Springer, 2020) Saygı, Sevilay; Erper, İsmail; Özer, Göksel; Türkkan, MuharremIn 2017, white cabbage (Brassica oleracea var. capitata f. alba L.) plants showing damping off and wirestem symptoms were collected to identify the causal pathogen from six fields in the Central Black Sea Region of TurkeyÖğe First report of rhizoctonia solani AG 4 HG-III causing root rot of pepper in Kyrgyzstan(Springer, 2020) Erper, İsmail; Özer, Göksel; Zholdoshbekova, Sezim; Yıldırım, Elif; Türkkan, MuharremPepper (Capsicum annuum L.) is one of the important vegetable species grown in Kyrgyzstan. In 2019, approximately 4% of mature pepper plants showed root rot symptoms in three fields located in Bishkek city.Öğe First report of root rot on strawberry caused by binucleate Rhizoctonia AG?G and AG?K in Kyrgyzstan(Springer, 2022) Erper, İsmail; Özer, Göksel; Yıldırım, Elif; Zholdoshbekova, Sezim; Türkkan, MuharremDuring the summer 2020, a disease was observed on strawberries [Fragaria×ananassa Duch., cultivar Senga Sengana] in four felds located in Chui Region, the northernmost region of Kyrgyzstan. Disease incidence was up to 10%. Diseased plants, exhibiting varying degrees of stunting, poor growth, black necrosis in basal petioles, and brown to dark brown discoloration or necrotic areas of crown and root tissue were picked from the feld to isolate fungi associated with symptoms.Öğe First report of southern blight caused by Athelia rolfsii on candyleaf in Turkey(Springer, 2020) Erper, İsmail; Özer, Göksel; Yıldırım, Elif; Özgen, Tolga; Türkkan, MuharremCandyleaf [Stevia rebaudiana (Bertoni) Bertoni] is grown for its sweet-tasting leaves containing steviol glicosides which are used as low-calorie sweetener. In June 2018, yellowing and drooping of leaves, with wilting of plants and brown sclerotia on a mass of white cottony mycelium at the collar region were observed with an incidence of up to 10% in two fields of candyleaf plants in Samsun province, TurkeyÖğe First report of southern blight on kale (Brassica oleracea var. acephala) caused by Athelia rolfsii in Turkey(Springer, 2020) Türkkan, Muharrem; Özer, Göksel; Benli, Halil İbrahim; Erper, İsmailKale (Brassica oleracea L. var. acephala) has been commonly cultivated in the Black Sea Region, Turkey. In 2017, wilting, subsequent death symptoms, and brown sclerotia and a mass of white cottony mycelium at the stem bases were observed on kale plants grown in three surveyed fields located in Ordu province, with a disease incidence of 12.5%.Öğe First report of verticillium dahliae causing verticillium wilt on kiwifruit in Ordu, Turkey(Springer, 2020) Türkkan, Muharrem; Şahin, Nusret; Özer, Göksel; Evgin, Zeynep; Yaman, Mehmet; Erper, İsmailDuring survey studies conducted in July 2016, symptoms of Verticillium wilt were observed with an incidence of up to 2% in three kiwifruit orchards in Ordu province of Turkey. Infected kiwifruits exhibited leaf chlorosis, scorch and defoliation, and discoloration in vascular tissue of the stem. After surface sterilization with 0.5% sodium hypochloride for 1 min, small pieces of stem tissue taken from diseased plantswere rinsed twice in sterile distilled water, and dried on sterile filter papers in a sterile cabinet.Öğe First report of white mold caused by Sclerotinia minor on safflower in Turkey(Springer, 2020) Erper, İsmail; Özer, Göksel; Yıldırm, Elif; Türkkan, MuharremSafflower (Carthamus tinctorius L.) is cultivated for oil that can be derived from its seeds and natural dyes in the petals of its flower. In May 2019, wilting of plants with white cottony mycelia, water-soaked lesions and dark-irregular shaped sclerotia (0.7 to 3.8 mm) on stem bases were observed with a general incidence of 6% in two fields surveyed in Samsun province, TurkeyÖğe Genetic diversity and pathogenicity of Rhizoctonia spp. isolates associated with red cabbage in Samsun (Turkey)(MDPI, 2021) Erper, İsmail; Özer, Göksel; Kalendar, Ruslan; Avcı, Şirin; Yıldırım, Elif; Alkan, Mehtap; Türkkan, MuharremAbstract: A total of 132 Rhizoctonia isolates were recovered from red cabbage plants with root rot and wirestem symptoms in the province of Samsun (Turkey) between 2018 and 2019. Based on the se quence analysis of the internal transcribed spacer (ITS) region located between the 18S and 28S ribosomal RNA genes and including nuclear staining, these 124 isolates were assigned to multinucle ate Rhizoctonia solani, and eight were binucleate Rhizoctonia. The most prevalent anastomosis group (AG) was AG 4 (84%), which was subdivided into AG 4 HG-I (81%) and AG 4 HG-III (3%), followed by AG 5 (10%) and AG-A (6%), respectively. The unweighted pair group method phylogenetic tree resulting from the data of 68 isolates with the inter-PBS amplification DNA profiling method based on interspersed retrotransposon element sequences confirmed the differentiation of AGs with a higher resolution. In the greenhouse experiment with representative isolates (n = 24) from AGs on red cab bage (cv. Rondale), the disease severity index was between 3.33 and 4.0 for multinucleate AG isolates and ranged from 2.5 to 3.17 for AG-A isolates. In the pathogenicity assay of six red cabbage cultivars, one isolate for each AG was tested using a similar method, and all cultivars were susceptible to AG 4 HG-I and AG 4 HG-III isolates. Redriver and Remale were moderately susceptible, while Rescue, Travero, Integro, and Rondale were susceptible to the AG 5 isolate. The results indicate that the most prevalent and aggressive AGs of Rhizoctonia are devastating pathogens to red cabbage, which means that rotation with nonhost-crops for these AGs may be the most effective control strategy. This is the first comprehensive study of Rhizoctonia isolates in red cabbage using a molecular approach to assess genetic diversity using iPBS-amplified DNA profiling.Öğe In Vitro Evaluation of Selenium Against Some Plant Pathogenic Fungi(2024) Özer, Göksel; Türkkan, Muharrem; Sönmez, Ferit; Kabakci, Hüseyin; Alkan, Mehtap; Derviş, SibelObjective: Selenium (Se) is garnering interest as a promising environmentally friendly element for controlling fungal pathogens in agricultural production. This study evaluated the impact of Se treatments, comprising sodium selenite (selenite) and sodium selenate (selenate) forms, on the growth of 10 plant pathogenic fungi. Materials and Methods: The impact of Se treatments on the mycelial growth and sporulation of fungi was assessed in in vitro conditions. Probit analysis was used to determine the concentrations of salts that induced a 50% reduction (EC50) in both mycelial growth and sporulation of fungi. Results: At the highest concentration (120 ppm), selenite demonstrated inhibitory effects on mycelial growth across various species, with a reduction in growth ranging from 6.82% to 62.46%. In contrast, selenate exhibited a broader spectrum of inhibition, affecting mycelial growth from 0% to 87.14%. Across different concentrations, Fusarium pseudograminearum displayed the highest sensitivity to selenite (EC50<24 ppm), followed by Bipolaris sorokiniana and Verticillium dahliae. Similarly, Colletotrichum coccodes exhibited the highest sensitivity to selenate treatment (EC50<24 ppm), followed by B. sorokiniana, Botrytis cinerea, Sclerotinia sclerotiorum, and V. dahliae. Both salts effectively inhibited sporulation across fungal species, with no significant difference observed. Colletotrichum coccodes, F. pseudograminearum, B. cinerea, F. culmorum, V. dahliae, and B. sorokiniana were significantly inhibited by selenite, while F. oxysporum exhibited lower inhibition. Similarly, these species, along with V. dahliae and F. oxysporum, were significantly inhibited by selenate, with slight differences between their inhibition percentages. EC50 values below 24 ppm were observed for C. coccodes, B. cinerea, F. culmorum, B. sorokiniana, and F. oxysporum, indicating potent inhibition of sporulation by both salts. Fusarium pseudograminearum required slightly higher concentrations for 50% inhibition. Verticillium dahliae showed higher sensitivity to selenate than selenite, with EC50 values of 33.16 ppm and below 24 ppm, respectively. Conclusion: The findings of this study contribute to our understanding of Se's antifungal potential across diverse plant pathogenic fungal species in sustainable agriculture. Further research is warranted to elucidate its mechanisms and optimize treatment protocols for disease management.Öğe Potential of Turkish Beauveria bassiana isolates for the management of the polyphagous planthopper, Orosanga japonica Melichar 1898 (Hemiptera: Ricaniidae)(Springer, 2022) Erper, İsmail; Ak, Kibar; Türkkan, Muharrem; Yıldırım, Elif; Alkan, Mehtap; Özer, GökselBackground Entomopathogenic fungi are a potential biological control agent for many pests. In this study, 14 native Beauveria bassiana isolates were molecularly identified and assessed for their virulence and mortality against adults of the polyphagous planthopper Orosanga japonica, Melichar (Hemiptera: Ricaniidae) a polyphagous sap-feeding insect, under laboratory conditions. Results Isolates obtained from naturally infected adults O. japonica were molecularly identified as B. bassiana by sequencing the internal transcribed spacer and 26S large subunit of ribosomal DNA. In the bioassay, the radial growth and sporulation of isolates significantly differed (P < 0.05). Concentration-time bioassays demonstrated that all isolates had a lethal effect on adult O. japonica at the concentration of 1 x 10(8) conidia ml(-1). The lethal times LT50 and LT90 values for each B. bassiana isolate, which indicate the time required to kill O. japonica, ranged between 2.44-3.19 and 3.78-5.01 days, respectively, at 20 degrees C, while their values were 1.74-2.76 and 2.76-4.10 days, respectively, at 25 degrees C depending on the native isolates. The concentration-mortality response showed a statistically significant difference between some isolates B. bassiana tested against adult O. japonica individuals (P < 0.05). With an LC50 value of 2.29 x 10(6) conidia ml(-1), the lowest effective EPF isolate for O. japonica was KA-78-14. The isolates caused 100% adult mortality in O. japonica within five days, while the mortality in the control group was less than 10%. Conclusions These findings suggest that some B. bassiana isolates were more virulent on O. japonica and may play an important role in the biocontrol of O. japonica in Turkey.
