Distribution and molecular identification of Meloidogyne spp. associated with tomato (Lycopersicon esculentum) cultivation in the Agro-ecological zone of the Guinean high savannah of Cameroon (Adamawa)

Meloidogyne represent a genus of plant-parasitic nematode. This nematode is serious crop pests, including tomatoes and is widespread in almost all regions of the world. Very little attention has been paid to these parasites in Cameroon and none in the agro-ecological zone of the Guinean high savannah. We therefore undertook this study to identify and assess the density of this nematode in this area. For this study, a total of 30 root samples were collected in tomatoes production areas from 4 districts and females Meloidogyne were isolated and counted. Specific identification was done by Polymerase Chain Reaction (PCR) using the markers C2F3/1108 and COX1. The genus Meloidogyne was thus identified in the 30 production basin sites of this zone. High densities of Meloidogyne were observed in 18 sites, with an average density of between 21-50 females per gram of fresh root. In contrast, low densities were noted at 12 sites with values between 6 and 19 females per gram of root. However, this distribution is function of the cropping period, soil texture, pH, organic matter content, soil saturation rate, and cropping practices (host or non-host plants and fallow practice). Electrophoretic profiles of Deoxyribonucleic Acid (DNA) amplified with C2F3/1108 and COX1 primers showed corresponding migrations at 1700 bp, 1100 bp and 421 bp characteristic of the presence of M. incognita/M. javanica, M. arenaria and M. incognita/M. hapla in this agro-ecological zone. In view of these results, which provide information on the distribution of Meloidogyne in this area, it seems necessary for producers to develop management strategies by improving preventive techniques and by piloting technical and cultural itineraries for the control of this plant pest.