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Wood vinegar, also known as pyroligneous acid (PA), is a liquid mixture with organic properties that results from the condensation of smoke produced by the charring or pyrolysis of wood and its residues during processing. The aims of this study were to determine the chemical composition and antifungal activity of three different PAs obtained from the pyrolysis of apricot kernels (AKPA), hazelnut shells (HSPA), and kermes oak (OPA) against Fusarium proliferatum. As a result of GC-MS analysis, o‑guaiacol (18.98–26.18%), creosol (11.08–16.38%), syringol (6.35–8.67%), p‑ethylguaiacol (5.53–10.04%), o‑creosol (4.0–10.33%) and phenol (2.34–7.90%) were identified as the main constituents of the tested PAs. AKPA was the most effective PA among the tested treatments, with MIC values of 3.5 µl ml−1for mycelial growth and 1.0 µl ml−1for conidial germination. Of the treatments tested under in vivoconditions, AKPA completely inhibited disease incidence at a concentration of 7.5 µl g−1soil. HSPA and OPA, on the other hand, significantly suppressed disease incidence at concentrations of 10.0 µl g−1and 12.5 µl g−1soil, respectively. All PA samples with MIC values caused significant deterioration of the morphological structures of the fungal hyphae. Since PAs showed promising antifungal activities against F. proliferatumboth in vitroand in vivo, they could be used as a cost-effective natural product as an environmentally friendly alternative to synthetic fungicides.

Wood vinegar, also known as pyroligneous acid (PA), is a liquid mixture with organic properties that results from the condensation of smoke produced by the charring or pyrolysis of wood and its residues during processing. The aims of this study were to determine the chemical composition and antifungal activity of three different PAs obtained from the pyrolysis of apricot kernels (AKPA), hazelnut shells (HSPA), and kermes oak (OPA) against Fusarium proliferatum. As a result of GC-MS analysis, o‑guaiacol (18.98–26.18%), creosol (11.08–16.38%), syringol (6.35–8.67%), p‑ethylguaiacol (5.53–10.04%), o‑creosol (4.0–10.33%) and phenol (2.34–7.90%) were identified as the main constituents of the tested PAs. AKPA was the most effective PA among the tested treatments, with MIC values of 3.5 µl ml−1for mycelial growth and 1.0 µl ml−1for conidial germination. Of the treatments tested under in vivoconditions, AKPA completely inhibited disease incidence at a concentration of 7.5 µl g−1soil. HSPA and OPA, on the other hand, significantly suppressed disease incidence at concentrations of 10.0 µl g−1and 12.5 µl g−1soil, respectively. All PA samples with MIC values caused significant deterioration of the morphological structures of the fungal hyphae. Since PAs showed promising antifungal activities against F. proliferatumboth in vitroand in vivo, they could be used as a cost-effective natural product as an environmentally friendly alternative to synthetic fungicides.

Spinach (Spinacia oleraceaL.), is a commercially important, widely grown and consumed vegetable in Turkey. In October 2020, typical symptoms resembling powdery mildew were observed on spinach plants in two inspected fields in Hatay province of Turkey. Circular discolorations patches accompanied with dull whitish fluffy sporulation were observed on both upper and lower leaf surfaces of plants. Conidiophores are typically formed from internal mycelium emerging through stomatal openings, either singly or in groups. Morphologically distinguished dimorphic conidia without distinct fibrosin bodies, are formed singly at the apex of conidiophores. No chasmothecia were found on heavily infected leaves over the course of the season. The identity of the disease agent was further confirmed sequencing of the ITS rDNA region of representative isolates by using ITS5/P3 and ITS1/ITS4 primers. Pathogenicity was confirmed through inoculation by touching freshly sporulating plant leaves onto the leaves of potted healthy spinach plants. Based on morphological characteristics of asexual fungal structures, molecular sequencing and pathogenicity test, the causal disease agent responsible for the spinach powdery mildew was identified as Leveillula taurica(Lév.) G. Arnaud (syn. = Oidiopsis haplophylli). To our knowledge, this is the first report of powdery mildew caused by L. tauricaon S. oleraceain Turkey.

Northern Leaf Blight caused by Exserohilum turcicumis the most significant disease in corn growing fields. The most important strategy for controlling Northern Leaf Blight is to use resistant varieties derived from qualitative and quantitative traits of corn grown around the world. Northern Leaf Blight threats to corn production because of the presence of E. turcicumraces and new races potential. Therefore, in order to obtain and use resistant lines at the regional level, it is necessary to determine pathogen races. For this reason, the objective of this study was to identify races of 50 E. turcicumisolates collected by the survey carried out on 7 important corn producing areas, Sakarya, Samsun, Ordu, Adana, Mardin, Osmaniye, and Mersin provinces, belonging to the Marmara, Black Sea, Mediterranean and Southeastern Anatolia regions of Turkey. In result, 8 different races of northern leaf blight, namely 0, 1, 2, 123, N, 1 N, 3 N, 12 N were found in Turkey. The most common races were identified as race 0 and race 1. In addition, molecular identification studies confirmed the validity of morphologically identified E. turcicumisolates.

Abstract: The objective of the current study was to characterize Fusarium oxysporum f. sp. radicis-cucumerinum isolates from cucumbers in Turkey in terms of pathogenicity, vegetative compatibility and amplified fragment length polymorphism (AFLP) variation. In the 2007 and 2008 greenhouse cucumber-growing seasons, surveys were conducted in Adana, Antalya, Hatay and Mersin provinces of the Mediterranean region of Turkey. Forty-seven fungal isolates of F. oxysporum were recovered from diseased cucumber plants. The pathogenicity of each isolate was tested on cucumber seedlings at the one-true-leaf stage. Forty of the 47 isolates of F. oxysporum were virulent on cucumber seedlings. Based on disease symptoms, the differential effect of temperatures of 17°C and 29°C on disease development, and the virulence on cucumber seedlings, these 40 isolates were identified as F. oxysporum f. sp. radicis-cucumerinum. Nitrate non-utilizing mutants were generated on minimal medium containing 1.5% KClO3 and their phenotypes were determined. Mutants in different phenotypic classes were paired on minimal medium; of 40 F. oxysporum f. sp. radicis-cucumerinum isolates, thirty-eight were placed into VCG 0260. Remaining two strains were assigned to VCG 0261. The AFLP primers produced a total of 180 fragments between 200 and 500 bp in length for the 30 isolates tested. At a genetic similarity of 0.71, the UPGMA analysis separated the isolates into two distinct clusters. The first cluster, AFLP I, included 28 isolates, of which all belonged to VCG 0260. Two strains in the second AFLP cluster both belonged to VCG 0261.