Fusarium proliferatum reported on date palms in Saudi Arabia
Date palm is an important crop in Saudi Arabia (15 million trees producing approximately 649,000 tons of fruits). In the Al Qassim and Al Medina Al Monawara regions, date palms showed symptoms of wilt and dieback, very similar to those caused by Fusarium oxysporum f. sp. albedinis (EPPO A2 quarantine pest). F. oxysporum f. sp. albedinis, the causal agent of Bayoud disease, is not present in Saudi Arabia and phytosanitary measures are taken to prevent its entry. The main fungal species isolated from diseased leaves and roots was identified as Fusarium proliferatum. Koch’s postulates were completed. F. proliferatum is a well-know pathogen, present in many countries on various crops (e.g. maize, rice and asparagus). According to pathogenicity tests on date palm seedlings, F. proliferatum should be regarded as a potentially dangerous pathogen of date palm in Saudi Arabia. Nine strains of F. proliferatum isolated from date palms were also tested for the production of toxins (beauvericin, fumonisin B1, fusaproliferin, fusaric acid and moniliformin). Two strains were able to produce all five toxins and all strains were able to produce at least three of these toxins. In addition to phytotoxic effects, these toxins have some effects on human health. More studies are needed on the possible risk of consumption of contaminated date palm fruit. This is the first time that F. proliferatum is reported as a pathogen of date palm in Saudi Arabia, and it is felt that further investigations are needed on the distribution of F. proliferatum in date palm-producing countries.
Sources
Abdalla, M.Y.; Al-Rokibah, A.; Moretti, A.; Mulè, G. (2000) Pathogenicity of toxigenic Fusarium proliferatum from date palm in Saudi Arabia.
Plant Disease, 84(3), 321-324.