Caractérisation pathogénique de Fusarium redolens et de Fusarium oxysporum f. sp. ciceris responsables de maladies telluriques du pois chiche (Cicer arietinum).

Abstract

Telluric diseases caused by Fusarium oxysporum f. sp. ciceris (FOC) and Fusarium redolens (FR), two fungal parasites, cause significant damage to chickpea (Cicer arietinum L.) crops. The aim of this study was to investigate the pathogenicity of Fusarium redolens and Fusarium oxysporum f. sp. ciceris on a chickpea line ILC 3279 (ICARDA), which is known to be susceptible to soil-borne diseases in Algeria. Differentiating the symptoms of these two pathogens will enable a field diagnosis to be made, which in turn will provide the basis for an appropriate control strategy. Chickpea plants are sown in a mixture of soil and potting mix (V/V) in plastic pots at a rate of 4 plants per pot, with 3 replicates per treatment. After 10 days, the plants were removed from the pots. They were then inoculated by immersing their roots in a conidial suspension containing 106 spores/ml for 15 minutes. Control plants were immersed in a sterile distilled water solution without inoculum. The first symptoms of the disease appeared 21 days after inoculation. The control plants showed no symptoms. In the light of the results obtained, it appears that the symptoms caused by FOC and FR are practically identical. However, the presence of brown necrosis in the stem xylem of inoculated plants indicates that the pathogen is FOC. This symptom was absent in the stem xylem of plants inoculated with FR. On the other hand, longitudinal sections taken from the taproots of plants inoculated with one or other parasite showed necrosis at root level. From a pathogenic point of view, we have shown that FR is as aggressive as FOC on chickpea