IN VITRO SUPPRESSION OF PHYTOPHTHORA CACTORUM AND VERTICILLIUM DAHLIAE POTENTIAL STRAWBERRY PATHOGENS BY BRASSICA TISSUES
Biofumigation is a term used to describe the supression of soil-borne pathogens and pest by the incorporation of Brassica plant into the soil. The suppressive effect of Brassica has been attributed to the glucosinolates, that have little biological activity, however, products formed from their hydrolysis have been demonstrated to be highly biocidal. Interest in biofumigation has increased recently due to prohibition of several synthetic pesticides and soil chemical fumigants. The objectives of this work were to evaluate the biocidal potential of Cruciferae species to control Phytophthora cactorum and Verticillium dahliae, potential strawberry pathogens, as well as, to investigate the biofumigant effect in different plant tissues of cruciferous crops during their growth cycle. Five Brassica species, namely B. carinata, B. juncea, B. nigra, B. napus and B. oleracea, were selected on the basis of their glucosinolates content. The studies were carried out for two consecutive growing seasons 2005-06 and 2006-07. Three sowing dates were considered from October to August. Samples were taken at three different stages of plant development: leaf (five leaves), flower (all the flowers open) and seed (seed in lower pods full size). Different concentrations of fresh macerated shoot tissue were assayed in glass jars. Three Phytophthora cactorum and two Verticillium dahliae isolates were tested and the colony radial growth measured daily. The results showed the existence of significant differences in the biofumigant effect depending on Cruciferae tested. B. carinata, B. juncea and B. nigra were the species with mayor suppressive effect. Seed was the most effective growth stage.
Zurera, C., Romero, E., Porras, M., Barrau, C. and Romero, F. (2009). IN VITRO SUPPRESSION OF PHYTOPHTHORA CACTORUM AND VERTICILLIUM DAHLIAE POTENTIAL STRAWBERRY PATHOGENS BY BRASSICA TISSUES . Acta Hortic. 842, 267-270
biofumigation, B. nigra, glucosinolates