Application of Molecular Markers for the Identification of Resistant Cowpea Varieties Against Fusarium Wilt in the Sudano-Sahalian Zone of Cameroon

Abstract

The current study aims to determine four cowpea varieties status under fusarium wilt disease by using Single Nucleotide Polymorphism (SNP) molecular markers potentially associated to cowpea resistant gene. Plant material was constituted by ten cowpea varieties with four varieties developed by the Institute of Agricultural Research for Development and six imported varieties from the International Institute of Tropical Agriculture. The experiment was carried out in completely randomized block with three replications. Infestation was performed by Fusarium oxysporum f.sp tracheiphilum isolate identified as the more virulent in the Far-North Region of Cameroon. The plants’ DNA was extracted by FTA Plantsaver cards method. Severity scale of the disease was noted from 0 to 5. The analysis of variance has revealed that significant differences exist among tested varieties as far as disease severity concern. IR15MA33, IT99K-573-2-1, IT82E-18 and IR15MA02 varieties with respectively 4.00, 3.67, 3.33 and 3.00 severity were identified susceptible. TVU109, IT98-503-1, CB46 and TV410 varieties with respectively 1.67, 1.67, 2.00 and 2.33 severities reveal the resistance signs against wilt fusarium. Among twenty-one tested markers, 2_31831, 2_27367 and 2_02374 have shown their potential associability to cowpea wilt fusarium resistance alleles. Potential parent’s resistant genes donors against this disease have revealed their resistance and relative information of different cowpea varieties status are henceforth available. Supplementary investigation is therefore necessary to establish genetic map of resistant gene.