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In the present study, the chemical composition and antibacterial activity of essential oils of bitter fennel (Foeniculum vulgare Mill. var. vulgare) and dill (Anethum graveolens L.) were investigated against food-borne and seedborne pathogenic bacteria. The chemical composition of bitter fennel and dill essential oils was analyzed by gas chromatography- mass spectroscopy. The major compounds found in the essential oils of bitter fennel and dill were estragole (37.6%) and limonene (33.1%), respectively. These essential oils have antibacterial activity against food-borne as well as seed-borne pathogenic bacteria. Fennel essential oil had the highest antibacterial activity against the food-borne bacterial pathogen Staphylococus aureus, while dill essential oil had the highest antibacterial activity against seed-borne pathogenic Clavibacter michiganensis subsp. michiganensis. Amongst all the bacterial species tested, the plant pathogenic agent Pseudomonas syringae pv. tomato had the greatest resistance to both essential oils. Considering the significant level of bacterial growth inhibition of seedborne and food-borne pathogens, essential oils or their components could be promising seed disinfectants or food additives in appropriate products. [ABSTRACT FROM AUTHOR]

The article reports the occurrence of crater rot caused by Rhizoctonia carotae on carrots in Turkey. Primary symptoms seen were a band of dark brown necrosis around the carrot crown and horizontal, brown, canker-like lesions, mostly on the crown and upper roots. Small pits subsequently developed beneath the lesions, which enlarged into sunken brown crater lines with a white, flocculent mycelium produced under high humidity. Fungal colonies were initially white, but turned brown with age. Dark brown to black sclerotia were occasionally produced.

The article focuses on alternaria leaf blight caused by Alternaria dauci on carrot in Turkey. The disease was extensive, with between 73 and 85% of fields inspected in the region being affected. Disease incidence of 65-90% was recorded in affected fields. The distribution of the disease in carrot fields was generally associated with high soil moisture levels, often corresponding to poor drainage. A fungus was consistently isolated from the margins of these lesions, onto potato carrot agar amended with streptomycin sulphate.

Reports on the plum rust on cultivated plum in the eastern Mediterranean region of Turkey. Defoliation of plum trees; Observation of the disease in almost all plum orchards in the region; Detection of teliospores within rusty brown pustules.

Inactivation of Botrytis cinerea inoculated into sour cherry juice, apricot and peach nectars was determined by pulsed electric fields (PEF) based on the measurement of germination tube elongation, spore germination rate and light and scanning electron (SEM) microscopic observations. With increasing electric field strength and processing time, germination tube elongation and spore germination were completely inhibited (P≤0.05). Microscopic observations revealed considerable morphological alterations such as cytoplasmic coagulation, vacuolations, hyphal shriveling and protoplast leakage. PEF processing of juice/nectars was very effective to inactivate B. cinerea. This method could be used to prevent product loss in fruit juice/nectars due to B. cinerea contamination. [ABSTRACT FROM AUTHOR]

Chinese wisteria, Wisteria sinensis (Sims) DC., is a woody, twining vine and is commonly cultivated as an ornamental for its foliage and striking, drooping racemes of white, pink, or lavender sweet pea-like flower. Distinct leaf spots were observed in several gardens, retail nurseries, and parks located in Hatay Province since May 2009. The primary infection zones are frequently observed on the leaf margins and apices, brown, up to 2 mm in diameter, and often surrounded by a yellow zone. Foliar symptoms are characterized by grayish, round, semicircular or irregular-shaped, numerous spots (up to 9 mm in diameter) with dark brown borders and the appearance of black, granular structure within the dead leaf tissues. A fungus was consistently isolated from symptomatic tissues on potato dextrose agar (PDA). Fungal colonies were initially white, becoming light to dark gray with the onset of sporulation with black, spherical to subspherical single-celled conidia (15 to 18 × 12 to 15 μm), which were borne on a hyaline vesicle at the tip of the conidiophore. These characteristics agree with published descriptions of Nigrospora sphaerica (Sacc.) E.W. Mason 1927 (1,3). To fulfill Koch's postulates, a conidial suspension (10 6 conidia per ml) collected from PDA cultures was used to spray inoculate leaves of potted 3-year-old Chinese wisteria plants. Inoculated plants were kept for 48 h in polyethylene bags and maintained in a controlled environment chamber at 20°C with a 12-h photoperiod. The bags were removed after 3 days. In addition, five 3-year-old plants were sprayed with sterile water to serve as controls. After 14 to 20 days, inoculated leaves showed infection symptoms similar to those observed on naturally infected leaves with N. sphaerica. The pathogen was reisolated from the margins of necrotic tissues, but not from the controls. Although N. sphaerica is frequently encountered as a secondary invader or as a saprophyte on many plant species, this fungal agent is also known as a leaf pathogen on several hosts worldwide (2,4). To our knowledge, this is the first report of N. sphaerica as a leaf pathogen of Chinese wisteria in Turkey or worldwide. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CMI, Kew, Surrey, UK, 1971. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory. Online publication. ARS, USDA. Retrieved 28 October from http://nt.ars-grin.gov/fungaldatabases/ , 2010. (3) P. M. Kirk. IMI Descr. Fungi Bact. 106:1056, 1991. (4) E. R. Wright et al. Plant Dis. 92:171, 2008.