IMPACT OF SELECTED SEED DRESSINGS ON SOIL MICROBIOLOGICAL ACTIVITY IN SPRING BARLEY CULTIVATION

摘要

Experiments were carried out to investigate the influence of selected seed dressings, Premis 025 FS (BASF; active substance (a.s.) - triticonazole, 25 g/L), Raxil 060 FS (Bayer; a.s. - tebuconazole, 60 g/L) and Kinto Duo 080 FS (BASF; a.s. - triticonazole, 20 g/L and prochloraz complex with copper, 60 g/L), on the total bacteria counts and numbers of oligotrophs, copiotrophs, actinomycetes and fungi in soils as well as on the activity of dehydro-genases and acid phosphatase under spring barley cultivation. The obtained results indicate that plant protection agents used in the experiment exerted varying impacts on changes in numbers of the analysed microorganism groups because the employed seed dressings were found both to stimulate and to inhibit the development of soil micro-flora. The majority of the examined fungicides caused an increase of total bacteria counts and numbers of oligotrophs and copiotrophs in the soil, but in the case of actinomycetes and fungi, their numbers were observed to fluctuate. Moreover, the performed experiment also revealed changes in the activity of the analysed soil enzymes. During the first dates of analyses, the majority of the applied seed dressings stimulated dehydrogenase activity in the soil, while during the last tests, their activity was inhibited. On the other hand, the activity of acid phosphatase in soil treated with different seed dressings declined.