Abstract
Protection of cucumber seedlings against damping off, caused byPythium debaryanum, was obtained by soaking the seeds in a solution of 1 ppm 6-azauracil (AzU), but not by treatment with a 10 or 100 ppm AzU solution. After the 1 ppm AzU treatment of the seeds, the rhizosphere microflora of the developing seedlings was changed; an increase of the bacterial population and a decrease of the fungal population was observed. SinceP. debaryanum is rather insensitive to AzU in vitro, it is suggested that the control of damping off is obtained in an indirect way, possibly via the microflora of the roots.
Samenvatting
Bescherming van komkommerzaailingen tegen aantasting doorPythium debaryanum werd verkregen na weken der zaden in een oplossing van 1 ppm 6-azauracil (AzU); 10 en 100 ppm AzU waren niet werkzaam. Na behandeling der zaden met 1 ppm AzU traden veranderingen in de rhizosfeermicroflora der kiemplanten op; de bacteriepopulatie nam toe en de schimmelpopulatie nam af. AangezienP. debaryanum in vitro vrijwel ongevoelig is voor AzU, wordt verondersteld dat de bescherming tegen aantasting door deze schimmel op indirecte wijze verkregen wordt, mogelijk via de microflora van de wortels.
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References
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Stânková-Opočenská, E., Dekker, J. Indirect effect of 6-azauracil on Pythium debaryanum in cucumber. Netherlands Journal of Plant Pathology 76, 152–158 (1970). https://doi.org/10.1007/BF01974323
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DOI: https://doi.org/10.1007/BF01974323