| Abstract: | The inoculum potential of Pofymyxa graminis was studied for 48 samples of Belgian soils and 8 samples from other European countries. After growing barley bait plants in tubes under controlled conditions on increasing dilutions of the samples in sterile sand, P. graminis was detected in 77% of the Belgian soils, the number of infection units calculated per g of soil ranging from 0.004 to 5.6. The inoculum potentials for the other origins were within these limits. The host range of P. graminis was studied by growing various Gramineae in the presence of cystosori extracted from barley roots cultivated on five soils. Barley was infected by all the isolates. Some isolates infected oat and/or rye but none wheat. |
