POPULATIONS OF FUNGI AND BACTERIA ON EARS OF CONVENTIONALLY AND ORGANICALLY GROWN WINTER WHEAT

摘要

In 2006 effects of two cropping systems: conventional and organic on population of bacteria, yeasts and filamentous fungi colonizing ears, at different stages of their development, of two winter wheat cultivars ('Roma' and 'Zyta') were compared. Populations of saprotrophic fungi, particularly yeasts, on ears grown under conventional cropping system were not significantly reduced by fungicides applied in the system as compared to the organic one. At the milk kernel stage total numbers of bacteria, yeasts and filamentous fungi, including Fusarium spp., on ears in the conventional system were even significantly higher than on the ears in the organic one. In the organic system wheat stands were thinner but taller (due to lack of any mineral fertilizersand plant growth regulators) and in consequence ears in the system kept moisture shorter than in the conventional system. It seems that this was the most important factor differentiating proliferation of microorganisms on ears under the two cropping systems.