A relationship between Bayoud disease severity and toxin susceptibility of date palm cultivars

Abstract

The Bayoud disease, caused by Fusarium oxysporum f. sp. albedinis (Foa, constitutes a serious threat to the date palm plantations in Morocco, Algeria and Mauritania. Three isolates of Foa were in vivo and in vitro examined for their pathogenicity and effect of culture filtrate phytotoxicicity. Our results indicated that, the agressivity of Foa strains was related to the effect observed with their culture filtrate and toxic fraction FII, which contains fusaric acid as a major compound, on detached leaves and seedling of date palm susceptible cultivars. This relationship between pathogenity and phytotoxic effect raises the question of the role of those phytotoxic compounds on beyond pathogenicity, and consequently their key role on breeding for resistance.