Effect of substrate mineral elements on the expression of oil palm fusarium wilt (Elaeis guineensis Jacq.)

This study aims at evaluating the effect of variation in mineral content of the substrate on the expression of Fusarium oxysporum f. sp. elaeidis (Foe), causal agent of oil palm Fusarium vascular wilt. The effects of the variation of Na, Cl, Ca, Mg, K in the undergrowth soil collected from the Pobè Forest and stored in the laboratory at Sèmè-Podji on the incidence of Foe were evaluated under controlled conditions at Sèmè-Podji on progeny of three susceptible oil palm crosses to Fusarium oxysporum. In order to test the effect of the mineral content (Na, Cl, Ca, Mg and K) of the substrate on the expression of fusarium, the potting soil was stored in the laboratory of Sèmè-Podji, under the effect of climatic and environmental hazards during different time intervals. The results showed that the K, Na, Mg and Cl contents of the substrate are significantly (p <0.001) different from one treatment to another within a year. In addition, the expression of Foe was influenced by the substrate contents of Na, Cl, Ca, Mg and K. Thus, a negative correlation existed between the fusarium rate and the contents of Mg, K, Cl, and Na. The fusarium rate does not appear to be correlated with Ca. A high content of K, Mg, Cl and Na in the substrate do not favour the expression of fusarium. These results should be further investigated in future studies to determine the precise levels of K, Mg, Cl and Na in the substrate that may inhibit the expression of fusarium. These results open up applications both in the management of fusarium in oil palm plantations and in controlled environments, in the framework of screening tests carried out for the selection of fusarium-resistant palms.