Incidence of the Two Date Palm Pathogens, Thielaviopsis Paradoxa and T. Punctulata in Soil From Date Palm Plantations in Elx, South-East Spain

The present study reports the frequent isolation of the two date palm pathogens Thielaviopsis paradoxa (de Seynes) Hohn and T. punctulata (Hennebert) Paulin, Harrington et McNew from soil of date palm plantations at Elx, south-east Spain, using dilution plate, direct soil plating or by soil treatment either with acetic acid or phenol. The two species showed a high isolation rate. T. punctulata detected from all samples (100% isolation rate), whereas, T. paradoxa showed 52% isolation rate. Total fungal colony count, ranged from 1.1×105-6 x105, CFU/g dry soil. Out of these, T. punculata comprised between 0.2-3.2% and T. paradoxa, between 0.5-4.4%. Both species were characterized by development of thick-walled aleuroconidia either singly (T. punctulata) or in chains (T. paradoxa) in addition to the phialoconidia. The widespread occurrence of the two pathogens in soil may contribute to the possibility of infection of newly transplanted offshoots of date palms.