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This study used seeds from five different summer pumpkin (Cucurbita pepo L.) cultivars (Çağlayan, Mert Bey, Sena Hanım, TG22, and TG38) and seeds collected from fruits in ten different provinces in Turkey where winter pumpkins (Cucurbita moschata Duch.) were cultivated. The seed coat and embryo were cultured and the seed-borne fungi were identified. Allophoma labilis and Didymella americana were detected in seeds (seed coat and embryo) of the cvs. Çağlayan and Mert Bey only, respectively. The seeds of both summer and winter pumpkins were contaminated with Alternaria alternata, Fusarium equiseti and Fusarium proliferatum, though their incidence varied depending on cultivar, province and seed parts. All species caused root and crown rot in seedlings in pathogenicity tests. Disease severities were caused by A. labilis, A. alternata, D. americana, F. equiseti and F. proliferatum at rates of 37.14–49.64%, 31.78%-42.50%, 31.29%, 14.17–50.00% and 25.14–51.07%, respectively. Colonial growth on different media, morphological and molecular characterization of the most pathogenic isolates from each species were defined. This is the first report in Turkey of A. labilis and D. americana in seeds of C. pepo, and Alternaria alternata, F. equiseti and F. proliferatum in seeds of both C. pepo and C. moschata, as well as the first pathogenicity record for these species by seed inoculation. [ABSTRACT FROM AUTHOR]

Context: Among biotic factors, bean anthracnose caused by Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi & Cavara is one of the most destructive diseases of common bean (Phaseolus vulgaris L.). Resistance in common bean genotypes is controlled by anthracnose resistance loci (designated Co). Aims: The objective of this study was to evaluate the presence of Co resistance genes in common bean genotypes from Turkey and to examine promising genotypes as candidates for parent plants in breeding studies. Methods: The presence of Co resistance genes in 693 common bean genotypes from 35 provinces of Turkey was determined by 12 SCAR (sequence characterised amplified region), RAPD (random amplified polymorphic DNA), STS (sequence-tagged site) and CAPS (cleaved amplified polymorphic sequence) markers. The disease reaction of 40 agronomically promising genotypes to different pathogen isolates was evaluated in a pot study. Key results: The results indicated the presence of Co-1 , Co-1 4 , Co-1 5 , Co-2 , Co-3 3 , Co-4 , Co-4 2 , Co-6 , Co - 10 , Co - 11 and Co - 13 resistance genes, alone or in combination; Co - 5 was not detected in any of the genotypes. Among the genotypes, Co-1 5 was the most frequent resistance source, followed by Co-4 , Co-6 and Co-11 , respectively. Common bean genotypes carrying Co-1 4 , Co-2 , Co-3 3 , Co-11 and Co-13 have been identified for the first time in Turkish germplasm. Five genotypes carrying the various combinations of Co-1 , Co-1 5 , Co-4 , Co-6 , Co-10 , Co-11 and Co-13 were resistant to all isolates in pathogenicity tests. Conclusions: This study is the most comprehensive to date on Co genes linked to the resistance of common bean genotypes throughout Turkey and provides an important gene pool for breeding studies into bean anthracnose. Resistant genotypes identified will be useful as parent plants in resistance breeding studies. Implications: Resistance genotypes carrying different Co genes to bean anthracnose will contribute significantly to the disease management strategy. Host plant resistance is the most economical and environmentally friendly method of protection against plant disease. This study examined Co genes in Turkish common bean genotypes linked to resistance to bean anthracnose. The study provides an important gene pool for breeding studies and identifies genotypes resistant to the pathogen. [ABSTRACT FROM AUTHOR]

Apple scab caused by Venturia inaequalis is one of the most economically important diseases of apple worldwide. Disease management is largely based on the frequent applications of fungicides, but fungicide resistance is a common problem. In this study, we monitored the development of resistance to four MBC, DMI and QoI group fungicides with different modes of action in V. inaequalis from apple orchards in Turkey. Sensitivity of V. inaequalis from 27 orchards in six provinces was evaluated to thiophanate‐methyl, myclobutanil, difenoconazole and kresoxim‐methyl by mycelium growth assay and molecular tools. Baseline sensitivity was determined in wild isolates of V. inaequalis from apple trees that had never been treated with any fungicides. EC50 value for thiophanate‐methyl, myclobutanil, difenoconazole and kresoxim‐methyl was 0.0992, 0.0315, 0.0048 and 0.0192 μg/ml, respectively. Of the 470 single spore isolates evaluated, 93.4% was very highly resistant to thiophanate‐methyl, while 27.5% and 50.2% were resistant and moderately resistant to myclobutanil, respectively. Difenoconazole and kresoxim‐methyl resistance were confirmed in 7.45 and 97% of the isolates tested, respectively. Molecular studies revealed that resistance to MBC fungicide, thiophanate‐methyl resulted from a mutation at codon 198 in β‐tubulin gene, while the G143A mutation of cytochrome b caused resistant to the QoI, kresoxim‐methyl. This study represents the first report of V. inaequalis resistance to several fungicides from apple orchards in Turkey. The resistance risk to these fungicides should be taken into consideration in the management of apple scab in Turkey. [ABSTRACT FROM AUTHOR]

During 2015–2017 growing seasons, seventy-one isolates of Rhizoctonia spp. were obtained from the samples collected from the sugar beet fields of Konya province, which is one of the most important sugar beet growing areas of Turkey. Anastomosis groups (AGs) of Rhizoctonia spp. isolates were determined by hyphal conjugation with the tester strains and sequence analysis of the rDNA ITS region. The obtained data confirmed the species identity of 61 isolates out of 71 as R. solani (AG-2-2-IIIB, AG-4-(HGI, HGII, HGIII), AG-5, AG-11) and the remaining 10 isolates as binucleate Rhizoctonia (AG-K, AG-A). Pathogenicity tests revealed that AG-2-2-IIIB, AG-4-(HGI, HGII, HGIII) and AG-K isolates were highly virulent on sugar beet. The disease severity of 71 isolates varied between 13 and 100%. Based on the virulence, the isolates formed four categories; (i) 11 isolates: non-pathogenic, (ii) 15 isolates: low virulent, (iii) 6 isolates: moderately virulent and (iv) 39 isolates: highly virulent. To our knowledge, the AGs of AG-4-(HGI, HGII, HGIII), AG-11, AG-A are first reports on sugar beet in Turkey and the AG-5, AG-11 and AG-K are first AG groups for Konya region. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the oomycetous pathogens causing root rot on sugar beet and test their control by seed treatment in Konya Province, Turkey. Oomycetous fungus-like pathogens of sugar beet were investigated using 866 plant samples collected at 2 growth stages, early seedling and late root, from fields in the Konya region of Turkey and 1 sample from the Thrace region. Herein, 10 oomycetous species belonging to 3 genera: Aphanomyces cochlioides, Phytophthora cryptogea, Ph. pseudocryptogea, Ph. megasperma, Ph. inundata, Pythium aphanidermatum, Py. helicoides, Py. heterothallicum, Py. sylvaticum, and Py. ultimum var. ultimum (Globisporangium ultimum var. ultimum) were discovered at various times with in the 2 growth periods, all of which were the first records for Turkey. A. cochlioides was the most serious pathogen, both in terms of its wide distribution and aggressiveness. The pathogen produced more than 90% disease severity when tested by soil infestation at the seedling stage, although it also occurred at the late root growth stage. Pythium species were also ascommon, such as A. cochlioides, the majority of which were very aggressive, producing more than 84% disease severity at the seedling stage, except for Py. aphanidermatum. Half-strength potato dextrose agar medium was found to be very useful for the isolation of all of the pathogens from the plant samples at both stages. Morphological features of all of the pathogens were abundantly produced when the pathogens were grown on amended grated carrot agar medium and culture disks of fungal growth of this medium were submerged in sterile and nonsterile soil extracts. Out of the 15 fungicide mixes tested, 2 mixes, thiram+metalaxyl+hymexazole and thiram+metalaxyl+hymexazole+ pyraclostrobin reduced seedling root rot caused by both A. cochlioides and Pythium ultimum var. ultimum, while the standard seed treatment fungicide mix of thiram+hymexazole was not effective against either of the pathogens. [ABSTRACT FROM AUTHOR]

This article reports the first occurrence of Neoscytalidium dimidiatum causing blight disease in maize (Zea mays) in Turkey. The disease was observed in a maize field in Şeyhçoban district of Şanlıurfa, Turkey, with a 3% incidence rate. The pathogen was isolated from symptomatic plants and identified based on its morphological characteristics and genetic sequencing. Pathogenicity tests confirmed that N. dimidiatum caused blight symptoms in maize plants. This finding represents the first report of N. dimidiatum associated with maize blight in Turkey. [Extracted from the article]

This article reports the first occurrence of Phytopythium litorale, a type of oomycete, associated with dieback disease in kiwifruit plants in Turkey. The disease was characterized by foliage desiccation, wilt, and internal reddish-brown discoloration. The researchers collected samples from affected plants and isolated oomycete-like colonies from the stem and root tissues. Genetic sequencing confirmed the identity of the isolates as P. litorale, with high similarity to strains found in cucurbits in Iran and kiwifruit vines in Italy. Pathogenicity tests confirmed that the pathogen caused root and collar rot symptoms in kiwifruit seedlings. This finding expands our understanding of the distribution and impact of P. litorale on kiwifruit crops. [Extracted from the article]

This article reports the first occurrence of Neocosmospora solani causing trunk and scaffold cankers on almond trees in Turkey. The symptoms observed included dark black lesions on the trunk, branch dieback, and brown discoloration of wood tissue. The pathogen was identified through morphological and molecular analysis, and its identity was confirmed as Neocosmospora solani. Pathogenicity tests showed that the inoculated branches developed canker lesions, while the control branches remained unaffected. This finding is significant as it represents the first report of N. solani associated with trunk and scaffold canker on almond trees in Turkey. [Extracted from the article]

Keywords: Pistachio; Crown rot; Root rot; Macrophomina phaseolina EN Pistachio Crown rot Root rot Macrophomina phaseolina 631 631 1 05/24/23 20230501 NES 230501 Pistachio ( I Pistacia vera i L.) is one of the most popular nuts for human consumption worldwide. The pathogen caused black lesions on inoculation point of all branch segments, whereas no symptoms were observed in the control branches. [Extracted from the article]

Neofusicoccum cryptoaustrale dieback and canker disease Walnut Keywords: Neofusicoccum cryptoaustrale dieback and canker disease Walnut EN Neofusicoccum cryptoaustrale dieback and canker disease Walnut 597 597 1 05/24/23 20230501 NES 230501 English walnut ( I Juglans regia i L.) is an important fruit tree in Turkey. [Extracted from the article]

Keywords: Leaf spot and crown rot disease; Neopestalotiopsis rosae; Strawberry EN Leaf spot and crown rot disease Neopestalotiopsis rosae Strawberry 315 315 1 03/16/23 20230201 NES 230201 In June 2021, leaf spot and crown rot symptoms were observed on approximately 4% of strawberry ( I Fragaria i × I ananassa i Duch.) Leaf spot and crown rot disease, Neopestalotiopsis rosae, Strawberry. [Extracted from the article]

Six weeks after inoculation at 25 °C, inoculated plants developed wilting and root rots with white mycelium, while control plants remained symptomless. The plants were inoculated by placing 4 g of wheat seeds colonized by I D. necatrix i in contact with the roots of each plant. Ten isolates from each separate plant showed characteristic pyriform swellings of 7 to 10 m wide in the septa union of mycelia. [Extracted from the article]

To confirm Koch's postulates, 5 pots containing 3 plants each were inoculated by placing 5 pathogen colonized sorghum grains near the crown of each plant about 1 cm below the soil surface. Keywords: Alstroemeria; Athelia rolfsii; Stem rot EN Alstroemeria Athelia rolfsii Stem rot 1163 1163 1 08/23/22 20220801 NES 220801 I Alstroemeria i spp. (Lily of the Inca, Peruvian Lily) is a cutting garden flower widely grown in many countries. Inoculated plants showed the same symptoms observed in the greenhouse. [Extracted from the article]

To identify Fusarium species associated with diseases of root and basal plate of onion, surveys were conducted in seven provinces of Turkey in 2007. Samplings were performed in 223 fields, and 332 isolates belonging to 7 Fusarium spp. were obtained. The isolates were identified as F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. proliferatum, F. redolens, and F. culmorum based on morphological and cultural characteristics. Also, species-specific primers were used to confirm the identity of Fusarium species. F. oxysporum was the most commonly isolated species, comprising 66.57% of the total Fusarium species. F. redolens was identified for the first time in onion-growing areas of Turkey. Selected isolates of each species were evaluated for their aggressiveness on onion plant. F. oxysporum, F. solani, F. acuminatum, F. proliferatum, and F. redolens were highly pathogenic, causing severe damping-off on onion plants cv. Texas Early Grano. Inter-simple sequence repeats (ISSR) markers revealed a high degree of intra- and interspecific polymorphisms among Fusarium spp. [ABSTRACT FROM AUTHOR]

Seventy-five isolates of Fusarium oxysporum f.sp. cepae, the causal agent of basal plate rot on onion, were obtained from seven provinces of Turkey. The isolates were characterized by vegetative compatibility grouping (VCGs) and restriction fragment length polymorphism (RFLP) analysis of the nuclear ribosomal DNA intergenic spacer region (IGS). Forty-eight vegetative compatibility groups were found, each containing a single isolate. Only one isolate formed strong heterokaryons with the reference isolates of VCG 0423. Five isolates were heterokaryon self-incompatible. Restriction fragment analysis with six different enzymes revealed 13 IGS types among 75 F. oxysporum isolates from Turkey as well as 16 reference isolates from Colorado, USA. The majority of single-member VCGs produced identical RFLP banding patterns with minor deviations, considerably different from those of the reference VCG isolates. These results suggested that isolates of F. oxysporum f.sp. cepae in Turkey derived from distinct clonal lineages and mutations at one or more vegetative compatibility loci restrict heterokaryon formation. [ABSTRACT FROM AUTHOR]

The distribution of mating types of Ascochyta rabiei (teleomorph: Didymella rabiei) was studied on isolates collected from chickpea growing areas of Central Anatolia. Mating type assessments of 45 isolates from 6 different provinces were conducted under laboratory conditions. After keeping for 5-6 weeks, the pseudothecial development and ascospore production were observed on chickpea stem pieces that were incubated in 8 ± 1 °C and 85% relative humidity. Both mating types were found in all the provinces, except for Kayseri and Sivas. The majority of the isolates belonged to Mat 1-1 (57.8%) and the others (42.2%) to MAT 1-2. Additionally, the mating types of A. rabiei were differentiated from each other using the multiplex PCR method with the primers Com1, Tail 5, and SP21. MAT 1-1 isolates were amplified to approximately a 460 bp fragment and MAT 1-2 isolates to a 700 bp fragment, in accordance with the discrimination of mating type groups with conventional methods. [ABSTRACT FROM AUTHOR]

Keywords: Apple; Neoscytalidium dimidiatum; Canker; Dieback EN Apple Neoscytalidium dimidiatum Canker Dieback 429 429 1 02/24/22 20220201 NES 220201 Turkey is one of the leading producer of apples worldwide. To our knowledge, this is the first report of I N. dimidiatum i associated with dieback and canker of apple in Turkey (Farr and Rossman [2]). [Extracted from the article]

To our knowledge, this is the first report of I N. novaehollandiae i associated with cherry dieback and canker in Turkey (Farr and Rossman [1]). Keywords: Cherry; Neoscytalidium novaehollandiae; Canker; Branch dieback EN Cherry Neoscytalidium novaehollandiae Canker Branch dieback 391 391 1 02/24/22 20220201 NES 220201 Turkey is the largest cherry ( I Prunus avium i L.) producer in the world. [Extracted from the article]

In June 2021, canker and wood necrosis were observed on approximately 25% of hazelnut trees within an area of 4 hectares located in Sakarya province of Turkey. Keywords: Botryosphaeria dothidea; Corylus avellana; Wood necrosis; Canker EN Botryosphaeria dothidea Corylus avellana Wood necrosis Canker 467 467 1 02/24/22 20220201 NES 220201 Hazelnut ( I Corylus avellana i ) is one of the most economically important tree nut crops in Turkey. Disease symptoms were dark brown dried-up branches, brown necrosis of the internal tissues, and death of the trees. [Extracted from the article]

Keywords: Cyclamen persicum; Fusarium wilt; Turkey EN Cyclamen persicum Fusarium wilt Turkey 469 469 1 02/24/22 20220201 NES 220201 I Cyclamen persicum i is a flowering species, widely cultivated as an ornamental plant worldwide. After 3 weeks, typical wilt symptoms were observed on inoculated plants, but no symptoms were observed on control plants. [Extracted from the article]

Botrytis disease of tea was reported for the first time from Rize, Turkey. The causal agent was identified as Botrytis cinerea based on morphological and cultural characteristics. Also, the species-specific PCR assays confirmed the identification of all B.  cinerea isolates. The pathogen caused blight of shoots, buds, flowers and young leaves, shoot canker and leaf spots. The disease was observed in Rize central district and Derepazarı, Çamlıhemşin, Çayeli, Pazar, Hemşin, İkizdere, Ardeşen and İyidere districts. [ABSTRACT FROM AUTHOR]

Symptoms typically associated with RRCR, including dark brown to black lesions at the base of the petioles or circular to oval, localized, dark lesions at the taproot, were observed on sugar beet plants. Sugar beet, Rhizoctonia solani, Anastomosis groups, Turkey Keywords: Sugar beet; Rhizoctonia solani; Anastomosis groups; Turkey EN Sugar beet Rhizoctonia solani Anastomosis groups Turkey 377 377 1 02/25/21 20210201 NES 210201 During the spring of 2016, 1006 sugar beet samples displaying Rhizoctonia root and crown rot (RRCR) symptoms were collected from several fields in Konya, Turkey. [Extracted from the article]

Common bean (Phaseolus vulgaris L.) is the most important grain legume. Crop production of common bean is affected by a number of diseases, such as Rhizoctonia root rot, being detected worldwide. Herein, we aimed to genetically and pathologically characterize Rhizoctonia solani isolates obtained from different provinces in Turkey. Anastomosis groups (AG) and subgroups of isolates were identified based on the sequence analysis of the rDNA-ITS region. The most prevalent subgroup was AG-4 HGIII, according to BLAST analysis and the phylogeny of resultant sequences, followed by AG-4 HGI and AG-4 HGII, respectively. iPBS retrotransposons highly supported the phylogenetic tree and provided a high level of genetic variability among isolates to discriminate AG subgroups. The results indicated that the iPBS DNA marker system based on retrotransposons could be used to discriminate Rhizoctonia isolates relying on AG grouping. The virulence of the pathogen isolates changed from 3.67 to 5 based on the agar-plate assay on the susceptible cv. Gina. The reactions of thirty common bean cultivars were also evaluated against the most aggressive isolate in each subgroup. The reaction assay showed significant differences among both isolates and cultivars; the highest disease severity among cultivars was observed to AG-4 HGI, followed by AG-4 HGIII and AG-4 HGII, respectively. None of the cultivars showed resistance to all AG subgroups. Screening of AGs among the isolates and selecting cultivars are critical to managing Rhizoctonia disease due to the range of host suitability according to AG subgroups. • IPBS is as effective as DNA sequence analysis in distinguishing R. solani subgroups. • Among cultivars, AG-4 HGI showed the highest disease severity, followed by AG-4 HGIII, AG-4 HGII. • Seher Yıldızı, Sarıkız, Perolar were resistant to AG-4 HGII-HGIII, sensitive to HGI. [ABSTRACT FROM AUTHOR]

Apple scab caused by Venturia inaequalis is one of the major diseases of apple orchards worldwide. Genetic variability in pathogen populations present new strategies for management the disease and breeding studies. In this study aimed to evaluate genetic diversity and population structure of 81 V. inaequalis isolates obtained from six provinces of Turkey. Twenty-six iPBS and 20 ISSR primers were investigated for their ability to produce polymorphic bands among the pathogen isolates. The mean percentage of polymorphic bands per primer was 85.48 and 84.87 for iPBS and ISSR markers, respectively. The dendrogram derived from UPGMA cluster analysis based on the combined dataset of iPBS and ISSR markers classified the isolates into two main groups with a genetic similarity of 69%, which no relationship between distribution and geographical origin of the isolates. The dendrogram of Nei's genetic distances Isparta and Sivas populations clustered separately other populations. STRUCTURE analysis showed four populations (K = 4) with the highest mean value of Ln likelihood (−3067.0). The average genetic differentiation (G ST) among all populations was 0.105. The overall gene flow (N M) was high level of 4.260. The analysis of molecular variance (AMOVA) showed that 96% of the variation was between the isolates within populations, compared to only 4% was among populations. iPBS marker based on the LTR retrotransposons has been tried for the first time to evaluate intraspecific variation among the isolates of V. inaequalis. Both iPBS and ISSR markers were useful, informative and reliable tools for investigating the genetic diversity of V. inaequalis. The results obtained from the present study provide detailed information about population genetic structure of V. inaequalis in Turkey. These study also will provide new approaches for plant breeders and disease management strategies. • First genetic diversity of V. inaequalis with iPBS retrotransposons marker from both Turkey and world. • No relationship between distribution and geographical origin of the V. inaequalis isolates. • Sexual recombination highly effective on genetic variability of V. inaequalis populations. [ABSTRACT FROM AUTHOR]