Zbiorowiska mikroorganizmów w glebie spod leśnej uprawy żeń-szenia amerykańskiego

The investigations were carried out in 2003-2004 on American ginseng (Panax quinquefolium L.) plantation localised in the mixed forest in Trzciniec (Lubelski province). The object of the study was the soil from ginseng culture protected by the biological and chemical method. In the experiment there was also control plot - without any protection during plants vegetation. There were also analysed the infected roots of ginseng plants. Microbiological analyses showed that soil from control plots was characterised by the smallest average total number of bacteria. In 1 g of dry weight of soil after Polyversum application there was stated the highest number of bacterial colonies from Bacillus and Pseudomonas genus. The highest number of fungal colonies was obtained in 1 g of dry weight of soil on the control plots. The highest number of saprophytic fungi (including those with antagonistic character) was obtained from the soil where the biological plant protection was applied. Generally, independently of a plant protection method, American ginseng plants were affected by Alternaria alternata, Cylindrocarpon spp., Fusarium spp., Pythium irregulare and Rhizoctonia solani