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Cabbage (Brassica oleracea L. var. capitata L.) is an important crop in Poland. Symptoms of a disease affecting cabbage were observed in 2012 and 2013 both in mid-August during the growing season and during storage in January and February. The disease affected about 30 to 40% of crops grown on ~9,000 ha over three locations: Charsznica in south Poland and Bedlno and Skierniewice in central Poland. Circular, watery lesions ranging from 10 to 60 mm in diameter on the surface of affected cabbage heads included whitish aerial mycelium that developed orange sporodochia in the center of each lesion. After 2 to 3 weeks, infection covered each entire cabbage head. A fungal pathogen was isolated from the orange lesions and from infected internal tissue. After sterilization of the excised tissue in 70% ethanol, the sections were each rinsed twice with sterilized water, dried on sterilized filter paper, and plated onto potato dextrose agar (PDA). Isolations consistently yielded morphologically homogeneous fungal colonies with abundant aerial mycelium that ranged from yellow to brownish yellow. The fungus produced pigmentation that changed the agar medium from dark yellow to brownish-burgundy. The mean colony growth was 66 mm after 7 days at 25°C. The fungus formed macroconidia, but microconidia and chlamydospores were not observed. Macroconidia were slender, slightly falcate, usually 3- to 5-septate, 44.7 to 60.7 × 3.7 to 5.5 μm, and formed in abundant orange sporodochia. On PDA, the isolates lost the ability to form sporodochia. Morphological and cultural features were typical of those of F. avenaceum (Fries) Saccardo (2). Koch's postulates were conducted to establish pathogenicity of each of four of the isolates on cabbage heads of the cv. Jaguar F1 (Bejo Seeds, Poland). The outer leaf of each head was inoculated with an 8-mm-diameter PDA plug colonized by the appropriate isolate (four cabbage heads/isolate), and the heads stored in a growth chamber at 25°C. After 5 to 7 days, lesions similar to those observed on naturally infested cabbage were observed on all the inoculated cabbage leaves. Four cabbage heads treated similarly with water as a control treatment remained symptomless. The experiment was repeated. DNA extracted from two of the four isolates was subjected to a PCR assay with primers ITS5 and ITS4 (4) for species identification based on the ITS1 and ITS2 sequences of ribosomal DNA (rDNA). The two sequences differed by 1 bp in the ITS2 region and had 100% identity with ITS sequences of F. avenaceum Accession Nos. AY147283 and AY147285 in GenBank. The sequences were deposited in GenBank as KM189440 and KM189441. Descriptions of fusarium head rot of cabbage in the United States (1) and Canada (3) were consistent with these observations in Poland. To our knowledge, this is the first report of F. avenaceum causing head rot of cabbage in Poland and in Europe. References: (1) H. R. Dillard and A. C. Cobb. Phytopathology 96:30. 2006. (2) J. F. Leslie and B. A. Summerell. Page 132 in: The Fusarium Laboratory Manual, Blackwell Publishing, Hoboken, NJ, 2006. (3) R. D. Peters et al. HortSci. 42:737. 2007. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

The herbicides Treflan EC 2 (24% trifluralin) and Devrinol 50 (50% napropamid) applied separately decreased efficiently the incidence of club-root on cabbage seedlings in pot experiments. If these herbicides were applied together with the fungicide Bavistin {50% carbendazim) the control of the disease was in some cases more efficient, as compared with Bavistin used alone. The higher the organic matter content in the soil, the lower the phytotoxicity and dub-root controlling activity of herbicides. Thus, on peat soil the 'herbicides could be applied in much higher rates than on pseudopodsolic soil.

Possibilities of integrated protection against Alternaria leaf spot (Alternaria spp.) of Chinese cabbage using three different groups of plant protection products Możliwości integrowanej ochrony kapusty pekińskiej przed czernią krzyżowych (Alternaria spp.) z zastosowaniem trzech różnych grup preparatów Agnieszka Włodarek*, Jan Sobolewski, Józef Robak SummaryThe aim of the field experiments carried out in 2011-2013 was to evaluate the usefulness of fungicides, natural products and a growth stimulator used in integrated protection against Alternaria leaf spot of Chinese cabbage (Alternaria spp.). The following products were evaluated: two fungicides -Amistar 250 SC and Signum 33 WG, the natural products -Timorex Gold 24 EC and a strawberry extract and a growth stimulator Huwa-San TR 50. The examined products showed high effectiveness in protection of Chinese cabbage against Alternaria leaf spot.

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