The present research was undertaken to study the antifungal activities of Origanum onites L. and Ziziphora clinopodioides L. essential oils against three different isolates (M1-5, M2-1 and M3-5) of Botrytis cinerea (in vitro tests) and to investigate the vapor contact impacts on fungus and strawberry fruit quality (in vivo tests). Antifungal activities of these oils were tested by following the poisoned food technique at four different concentrations (0.25, 0.50, 1.00 and 2.00 mL/L) against B. cinerea. In vitro studies suggested that the 0.50 mL/L and 1.00 mL/L doses of O. onites and 1.00 mL/L and 2.00 mL/L doses of Z. clinopodioides provide high mycelial growth inhibition, 85.29–94.12% and 39.12–94.12%, respectively, by direct addition to food. Thus, these doses were tested in in vivo conditions, as a vapor contact treatment against two isolates (M1-5 and M3-5) of B. cinerea inoculated on strawberry cv. Camarosa fruits. Results showed that both O. onites and Z. clinopodioides essential oils have a moderate to high impact on the prevention of gray mold. The oils were also found to have a slight to moderate impact on weight loss and the loss of soluble solids concentration. Overall, the results demonstrated that the tested oils are a potential biodegradable alternative to fungicides.

Soil organic matter (SOM) is a heterogeneous mixture of materials ranging from fresh plant tissues to highly decomposed humus at different stages of decomposition. Soil organic carbon (SOC) status is directly related to the amount of organic matter in soil and therefore is generally used to measure it. Soil carbon sequestration refers to the removal of carbon (C) containing substances from the atmosphere and its storage in soil C pools. The soil microbial community (SMC) plays an important role in the C cycle, and its activity is considered to be the main driver of differences in C storage potential in soil. The composition of SMC is crucial for maintaining soil ecosystem services, as the structure and activity of SMC also regulate the turnover and distribution of nutrients, as well as the rate of soil organic matter (SOM) decomposition. Here, we applied fungi on the soils taken from two fields, one used as a pasture and one for agriculture (wheat cultivation), in a histosol in the eastern part of Türkiye and investigated the changes in the organic carbon and enzyme activity contents of the soils at the end of the 41-day incubation period. In the study, four different fungal species (Verticillium dahliae (SOR-8), Rhizoctonia solani (S-TR-6), Fusarium oxysporum (HMK2-6), and Trichoderma sp.) were used and catalase, urease, and alkaline phosphatase activities were examined. Results showed that the values of SOC were V. dahliae (7.46%), Trichoderma sp. (7.27%), R. solani (7.03%), Control (6.97%), and F. oxysporum (6.7%) in pastureland and were V. dahlia (4.72%), control (4.69%), F. oxysporum (4.65%), R. solani (4.37%), and Trichoderma sp. (4.14%) in agricultural land, respectively. SOC and soil enzyme activities were significantly affected by land use types (p < 0.05). The higher SOC and enzyme activities were observed in pastureland. Finally, it was determined that soil organic carbon and soil enzyme activities were affected by fungi. This study is important in terms of revealing that the effects of fungi on soil organic carbon and enzyme activities are different in various land types.

This study was carried out to determine anastomosis groups and pathogenicity of 166 Rhizoctonia isolates obtained from strawberry plant samples in Erzincan province, Turkey during 2009 and 2010. Rhizoctonia species and anastomosis groups (AGs) of all the isolates were determined using classical techniques. Molecular characterizations of the selected Rhizoctonia isolates were performed by sequence analysis of the internal transcribed spacer (ITS) regions of the ribosomal DNA (rDNA). Of these, 155 isolates were identified as binucleate (BN) Rhizoctonia spp., and 11 isolates were as multinucleate (MN) Rhizoctonia solani. Three BN Rhizoctonia isolates were identified as Ceratobasidium albasitensis, the remaining BN Rhizoctonia isolates were assigned to AG-A (54 isolates), AG-E (11 isolates), AG-G (37 isolates), AG-H (6 isolates), AG-K (44 isolates). Rhizoctonia solani isolates were classified as AG-2-1 (4 isolates), AG-4 HGII (3 isolates) and AG-5 (4 isolates). Pathogenicity test was conducted on strawberry plants (cv. Fern), and AG-G isolates were found to constitute the highest disease severity than other species or AGs of Rhizoctonia obtained in this study. BN Rhizoctonia AG-E, R. solani AG-5 and C. albasitensis were first time reported on strawberry plants in Turkey. Keywords: Anastomosis group, black root rot, Ceratobasidium albasitensis, rDNA-ITS region, Rhizoctonia, strawberry

In this study, the efficacy of the essential oil of Mentha longifolia, Achillea arabica and Artemisia absinthium plants were evaluated against important soil-borne fungal pathogens as Verticillium dahliae, Rhizoctonia solani, and Fusarium oxysporum. Essential oils were obtained from plants by hydrodistillation method and the chemical components of essential oils were determined by analyzing by gas chromatography-mass spectrometry. The main components found as piperitone oxide (13.61%), piperitenone oxide (15.55%), pulegone (12.47%), 1-menthone (5.75%), and camphor (5.75%) in M. longifolia, á-selinene 13.38%, camphor 13.34%, L-4-terpineneol 8.40%, (–)-á-Elemene 7.01%, 1,8-cineole 4.71%, and (–)-spathulenol 3.84% in A. arabica, and á-thujone (34.64%), 1,8-cineole (19.54%), pulegone (7.86%), camphene (5.31%), sabinene (4.86%), and germacrene-d (3.67%) in A. absinthium. The antifungal activities of the oils were investigated 0.05, 0.1, 0.25, 0.5, 1.00, and 2.00 μl/ml concentrations with the contact effect method. M. longifolia oil (1.00 and 2.00 μl/ml) has displayed remarkable antifungal effect and provided 100% inhibition on mycelial growth of V. dahliae, R. solani and F. oxysporum. The results obtained from this study may contribute to the development of new alternative and safe methods against soil-borne fungal pathogens.

Amaç: Domates bitkisinde hastalığa neden olan toprak kökenli funguslara karşı, domates bitkilerinin rizosferinden izole edilen rizobakterilerin biyolojik mücadele potansiyellerinin belirlenmesidir. Materyal ve Yöntem: 10 farklı rizobakteri izolatının bitki gelişimini teşvik etme ve 3 farklı fungal patojene (Fusarium oxysporum HMK2-6, Rhizoctonia solani HB-66, Verticillium dahliae YY-14) karşı biyokontrol potansiyelleri in vitro koşullarda belirlenmiştir. Ayrıca, aralarından seçilen iki rizobakteri izolatının R. solani’ye karşı etkisi in vivo koşullarda belirlenmiştir. Araştırma Bulguları: Pseudomonas chlororaphis T142 strainin %19.9 ve Bacillus subtilis T139 straininin %11.9 oranında biyokontrol etki göstererek R. solani’nin hastalık şiddetini azalttığı tespit edilmiştir. Ayrıca Bacillus subtilis T139 izolatı, domates bitkilerinin kök gelişimini kontrole göre artırmıştır. Sonuç: Çalışmada kullanılan rizobakteri izolatları domateste R. solani’nin biyolojik mücadelesi için ümit vadedici sonuçlar ortaya koymuştur.

Bitkilerin sağlıklı bir şekilde gelişimlerini devam ettirebilmeleri için mutlak gerekli besin elementleri bulunmakta, bu besin elementlerinin eksikliği veya fazlalığı durumunda bitkilerde hastalıklara karşı uygun ortam oluşmaktadır. Bu çalışma; çilekte Verticillium dahliae tarafından oluşturulan Verticillium solgunluk hastalığının bitkilerin P, Ca, K, Mg, Na, B, Mn, Fe, Zn ve Cu içeriğinde nasıl bir değişim meydana getirdiğini tespit etmek amacıyla yürütülmüştür. Bu amaçla çilek bitkilerinden elde edilen farklı vejetatif uyum gruplarına (VCG 2A, VCG 2B, VCG 4B ve VCGx) ait 19 V. dahliae izolatı incelenmiştir. Kontrol bitkileri dahil V. dahliae izolatları ile enfekte edilen toplam 200 bitkide besin elementi analizleri yapılmıştır. Kontrol bitkileri ile karşılaştırıldığı zaman V. dahliae enfeksiyonu çilek bitkilerinin P, Ca, K, Mg, B, Mn ve Cu içeriklerinde değişime sebep olmuştur. Bununla birlikte, enfekte olmuş bitkilerin Na, Fe ve Zn içerikleri kontrol bitkilerinden farklı bulunmamıştır.