EN
Condition of colonies of three breeds of the honey bee, Augustowska, Crainian and Caucasica artificially invaded c by Varroa jacobsoni was monitored. In 1989 (3rd year of Varroa parasitism) both in invaded and in healthy colonies were examined wintering, losses of colonies and queens, productivity, intensity of infestation. In invaded non-treated colonies was noted bad wintering, (the most affected were colonies with Augustowska queen, the less affected with Crainian queen), disturbances in development during the whole season (number of worker cells with Augustowska queen was 20 602, with Caucasica queen 28 884 and with Crainian queen 33 357) low honey (0.9—3.4 kg) and wax (100—300 g) productivity. The extension of invasion in untreated colonies was very high and in September it reached in colonies with Augustowska queen 49.2%, Crainian queen 71.4% and Caucasica queen 63.0%. Similar level of invasion was noted in worker and drone brood. Infestated untreated colonies are very weak at the 3rd year of invasion and they have to die.