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In July 2020, a blight disease on lemon balm plants was observed with an incidence of up to 10% in three fields in Sanliurfa province, Turkey. The causal agent was identified as Neoscytalidium dimidiatum based on macro- and micro-morphological features of the colonies and sequencing of the translation elongation factor 1-α gene and the internal transcribed spacer region of rDNA. Re-isolation of N. dimidiatum from lemon balm plants showing blight symptoms was successfully established. To our knowledge, this is the first report of N. dimidiatum causing blight on lemon balm in Turkey and worldwide.

Considering the damage caused by fungicides to human health and problems such as microbial resistance, biological control against plant pathogens has started to gain importance worldwide. This research demonstrates a new, simple, cost-effective, and environmentally friendly method for synthesizing chitosan bionanocomposite (CBNC) from Morchella esculenta (L) Pers-extract (MEE). The antifungal property of the synthesized Morchella esculenta (L) Pers-chitosan bionanocomposite (MCBNC) against some plant pathogens was also evaluated. FTIR, XRD, FE-SEM, DSC, TGA, and BET were used to characterize the synthesized MCBNC. Mushroom-based chitosan nanoparticles were evaluated for antifungal activity against some fungal pathogens, including Neoscytalidium novaehollandiae, N. dimidiatum, Alternaria alternata, Verticillium dahliae, Bipolaris sorokiniana, and Colletotrichum sp. The findings obtained clearly showed that chitosan nanoparticles have antifungal activity. The results suggest that the chitosan nanoparticle can be used in the field to protect various crops from phytopathogens. Novelty impact statement Chitosan bionanocomposite (MCBNC) synthesis was performed for the first time using the wild mushroom Morchella esculenta, which has strong bioactive properties. It was observed that the bionanomaterial, which was characterized by FTIR, XRD, FE-SEM, DSC, TGA, and BET analyses, has high antifungal activity against plant pathogens such as Alternaria alternata and Bipolaris sorokiniana. MCBNCs synthesized by the green synthesis method can be an important area of use in the fight against plant pathogens, which corresponds to 1/3 of the world's agricultural production potential.

In 2020, a canker disease with dieback of branches and decline of various fig trees in Şanlıurfa and Mardin provinces of Turkey was observed. The causal pathogen was identified as Neoscytalidium dimidiatum based on morphological characteristics and phylogenetic analysis of ITS, tef1, and tub2 loci. Koch’s postulates were confirmed by successful re-isolation of N. dimidiatum only from plants inoculated with the pathogen. This is the first report of N. dimidiatum associated with dieback and canker of common fig in Turkey.

In June 2020, many plants exhibited symptoms of root rot and foliar blight in the experimental field of common sage in Sanliurfa province, Turkey. The pathogen was identified as Neoscytalidium novaehollandiae based on morphological characteristics and phylogenetic analysis of partial sequence of the transcription elongation factor 1-alpha gene and the internal transcribed spacer of rDNA. Koch's postulates were fulfilled by successful re-isolation of the pathogen from inoculated plants in the pathogenicity assay. To our best knowledge, this is the first report of N. novaehollandiae causing root rot and foliar blight of common sage worldwide.

In a recent survey of olive groves in the Southeast Anatolia Region of Turkey, a new and serious decline of olive trees, beginning with foliar scorching and then dieback of twigs, branches, and even whole trees, was observed for the first time. In more advanced stages of the disease, necrosis and cankers were observed on the bark of the trunk, branches, and twigs. Isolations from symptomatic tissues from multiple cultivars in diverse locations yielded Neoscytalidium dimidiatum, which were identified using ITS, tef1, and tub2 loci of genomic DNA, in combination with morphological data. In vitro studies showed that conidial germination, hyphal growth, and pycnidia formation of the pathogen were positively correlated with elevated temperatures. Wild type olive “Delice”, “Edincik Su”, and “Memecik” seemed like the most resistant cultivars on which disease severity values were the lowest among 14 screened olive cultivars in two experimental orchards under natural conditions. Pathogenicity tests showed that “Gemlik” was the most susceptible cultivar showing the largest cankers and extensive scorch lesions. Isolates caused canker but not leaf scorch on O. europaea cultivars “Arbequina” “Halhalı”, “Manzanilla”, “Nizip Yağlık”, and “Saurani”. Neoscytalidium isolates are likely to have a negative impact on the health of diverse olive groves, which are primarily confined to Mediterranean-type climatic regions. These findings suggest an increased risk of infection in environments with increasing temperatures, as is common in the Southeast Anatolia Region of Turkey. The information gathered in this study will be used to examine the disease's epidemiology and establish disease control initiatives. This is also the first report of N. dimidiatum infecting O. europaea in the world.

Lemon balm (Melissa ofcinalis L.) is native to the Eastern Mediterranean region and Western Asia and is a well-known medicinal plant of Lamiaceae due to its valuable aqueous and alcoholic extracts (De Sousa et al. 2004). In the summer of 2021, wilting and root rot were observed on about 20% of two-year-old M. ofcinalis cv. Melis plants in a feld of Koruklu village, Akçatepe district of Şanlıurfa, Turkey.

Lavender (Lavandula angustifolia Mill.) is a valuable medicinal and aromatic plant in Turkey, with a cultivated area of 2,218 hectares in 2020 (TURKSTAT 2021). In June 2020, wilting, extensive stem and leaf blight or necrosis were observed in two-year-old lavender plants cultivated in the experimental felds of the GAP Agricultural Research Institute, Şanlıurfa, Turkey.

In July 2020, a leaf blight disease with intense defoliation on Turkish oregano (Origanum onites L.) plants was observed in a pilot experiment feld in Akçakale and a commercial feld in Haliliye with an incidence of 5.4 and 11.7%, respectively, in Şanlıurfa province. After a surface-sterilization for 1 min with 1% NaOCl, isolations from symptomatic tissues of six afected plants for each feld consistently yielded a fungus with the same colony morphology on potato dextrose agar. Cultures were powdery with a thick aerial mycelium, initially white that changed from olive green to black within 10 days.

Common sage (Salvia officinalis L.) is a perennial herb or sub-shrub native to the eastern Mediterranean. In July 2020, symptoms of chlorosis, wilting, and root rot appeared in 25% of two-year-old S. officinalis cv. Elif plants in two fields (N 36°53'42.457'', E 38°55'34.777''; N 36°53'27.236'', E 38°55'38.618'') in Şanlıurfa, Turkey.

In this study, surveys were carried out during 2015and 2016 for wilt and root rot diseasescaused by Rhizoctonia solani, Macrophomina phaseolina, Fusarium oxysporum, and Fusarium solani in pepper fields in Adıyaman, Diyarbakır, Mardinand Şanlıurfa provinces of Turkey. The purpose of this study was to evaluatethe effects of different inoculationmethods (root dip, soil infestation with wheat bran and soil infestation withrice grain) on pathogenicities of R.solani, M. phaseolina, F. oxysporum and F. solani on pepper seedlings. Inoculated pepper seedlings (cv.İnan-3363) were left to grow for three months after transplanting under growthchamber conditions. Inoculation of infective rice-grain was used to testpathogenicity of all four fungi. Root dip inoculation methodwas used for F.solani and F.oxysporum when the soil was infested withwheat bran method for R. solani and M.phaseolina inoculation. All tested isolates resulted in the stem and rootrot, leaf chlorosis and bruising. To test the pathogenicity of fungi, soilinfestation with rice grain inoculation was the most suitable method. Alltested fungi induced similar foliarsymptoms, root rot severity and caused a similar reduction in dry root weightswhen rice-grain inoculum was used. With other inoculation methods, allpathogens similarly affected root rot severity. Whereas, F. oxysporum was the least virulent pathogen among tested fungiaffecting foliar symptom severity; for freshroot and plant weights, and dry root and plant weights; R. solani, M. phaseolina and F. solani were similarly virulent whenthese parameters were used. The results of the present study may have a useful connotation to monitor pepper seedlingsagainst these pathogens. In conclusion,we recommend rice-grain inoculation to test pathogenicities of R. solani, M. phaseolina, F. oxysporum and F. solanion various peppercultivars., In this study, surveys were carried out during 2015 and 2016 for wilt and root rot diseases caused by Rhizoctonia solani, Macrophomina phaseolina, Fusarium oxysporum, and Fusarium solani in pepper fields in Adıyaman, Diyarbakır, Mardin and Şanlıurfa provinces of Turkey. The purpose of this study was to evaluate the effects of different inoculation methods (root dip, soil infestation with wheat bran and soil infestation with rice grain) on pathogenicities of R. solani, M. phaseolina, F. oxysporum and F. solani on pepper seedlings. Inoculated pepper seedlings (cv. İnan-3363) were left to grow for three months after transplanting under growth chamber conditions. Inoculation of infective rice-grain was used to test pathogenicity of all four fungi. Root dip inoculation method was used for F. solani and F. oxysporum when the soil was infested with wheat bran method for R. solani and M. phaseolina inoculation. All tested isolates resulted in the stem and root rot, leaf chlorosis and bruising. To test the pathogenicity of fungi, soil infestation with rice grain inoculation was the most suitable method. All tested fungi induced similar foliar symptoms, root rot severity and caused a similar reduction in dry root weights when rice-grain inoculum was used. With other inoculation methods, all pathogens similarly affected root rot severity. Whereas, F. oxysporum was the least virulent pathogen among tested fungi affecting foliar symptom severity; for fresh root and plant weights, and dry root and plant weights; R. solani, M. phaseolina and F. solani were similarly virulent when these parameters were used. The results of the present study may have a useful connotation to monitor pepper seedlings against these pathogens. In conclusion, we recommend rice-grain inoculation to test pathogenicities of R. solani, M. phaseolina, F. oxysporum and F. solanion various pepper cultivars.