Colonisation of winter wheat grain by Fusarium spp. and mycotoxin content as dependent on a wheat variety, crop rotation, a crop management system and weather conditions.

Field experiments were conducted during three consecutive growing seasons (2007/08, 2008/09 and 2009/10) with four winter wheat (Triticum aestivum L.) cultivars - 'Bogatka', 'Kris', 'Satyna' and 'Tonacja' - grown on fields with a three-field crop rotation (winter triticale, spring barley, winter wheat) and in a four-field crop rotation experiment (spring wheat, spring cereals, winter rapeseed, winter wheat). After the harvest, kernels were surface disinfected with 2% NaOCl and then analysed for the internal infection by different species of Fusarium.

Growth of Penicillium verrucosum and production of ochratoxin A on nonsterilized wheat grain incubated at different temperatures and water content.

The results of two experiments with wheat grain inoculated with Penicillium verrucosum are reported. In Experiment I, wheat grain, containing 10, 20 and 30% water, was incubated for 2 weeks at 10, 15, 21 and 28 degrees C. In Experiment II, wheat grain, containing 14, 16, 18, 20 and 22% water, was incubated for 2 weeks at 10, 15, and 20 degrees C.

A simple, direct plating method, alternative to dilution plating, for estimation of the abundance of Penicillium verrucosum on incubated cereal grain.

Because dilution plating is more labor intensive than direct plating, we would like to propose the use of a direct plating technique for estimation of Penicillium verrucosum abundance in cereal grain in incubation studies, with use of very selective and indicative for the fungus agar DYSG medium. The proposed method is based on the measurement of the diameter of P. verrucosum colonies grown around cereal kernels placed on DYSG medium.

An attempt to protect winter wheat against Fusarium culmorum by the use of rhizobacteria Pseudomonas fluorescens and Bacillus mycoides.

Inoculation of wheat seeds with two strains of Pseudomonas fluorescens (III107 and II21) and two strains of Bacillus mycoides (JC192 and K184) isolated from winter wheat roots, as well as with one strain of P fluorescens (ID13) isolated from oat roots, reduced the negative influence of Fusarium culmorum on winter wheat in a 28 day pot experiment. The bacterial strains (especially III107 and chitinolytic JC 192) markedly increased the plant seedlings emergence and the plant biomass (the shoots weight up to 252%, and the roots weight up to 229%) in comparison to the experimental series with E culmorum alone. Also in a microplot experiment the yield of grain and straw of winter wheat, inoculated with the bacterial strains (especially JC192 and III107) and growing in soil contaminated with F.

An attempt to protect winter wheat against Gaeumannomyces graminis var. tritici by the use of rhizobacteria Pseudomonas fluorescens and Bacillus mycoides.

Pseudomonas fluorescens strains III107 and II21 and Bacillus mycoides strains JC192 and K184, stimulating growth of winter wheat, were chosen for the studies. The bacterial strains inhibited on agar nutrient medium the growth of Gaeumannomyces graminis var. tritici (Ggt)--the pathogenic fungus causing take-all on wheat.