Genetic diversity of rhizobia nodulating Arachis hypogaea L. in diverse land use systems of humid forest zone in Cameroon

Peanut (Arachis hypogaea) is one of the most important legume cultivated in the humid forest zone of Cameroon. However, in this country the diversity of rhizobial strains that can nodulate peanut was poorly understood. Forty-two strains from Arachis hypogaea were examinated by restriction fragment length polymorphism (RFLP) analysis of 16S-23S rDNA genes amplified by polymerase chain reaction (PCR). A considerable level of genetic diversity was determined among those peanut isolates. Eight composite genotypes were obtained from the combined data of the RFLP analysis with four endonucleases. A correlation between land use system and the diversity of peanut isolates was observed in the current study. The highest diversity was found in the cocoa farm and fallow and the lowest one in peanut farm. Our results have shown that the genotype richness diversity of peanut isolates depends on the land use system.