Mycoflora associated with Groundnut Seeds Collected from the three Senatorial Districts of Kwara State, Nigeria

Abstract

Groundnut seeds are of numerous benefits to mankind which can be reduced through contamination by fungal species, depending on the fungal species and their degree of contamination of the seeds. Occurrence of fungal species on groundnut seeds is of great public health concern. Therefore, it is essential to examine the different fungal species present. This study employed both the phenotypic and molecular methods to isolate and characterize the fungal species attributed to groundnut seeds.  The Zymo Research Group's recommended protocols were followed in order to extract the genomic DNA of each of the fungal species recovered. The PCR amplification and sequencing of the ITS region from the total genomic DNA of fungal isolates were conducted to molecularly identify them, using the NCBI database for comparison. The commonest mycoflora isolated from the stored groundnut seeds were Aspergillus flavus, A. niger, Alternaria alternate, Fusarium graminearum, Macrophomina phaseolina, Penicillium digitatum and Rhizopus stolonifer. The total incidence of each of them ranged from 8 - 32%. Among the three surveyed districts, Kwara Central exhibited the highest incidence of major mycoflora at 40%, while Kwara North had the lowest at 27%. Aspergillus niger demonstrated the highest incidence among the fungal species found in groundnut seeds collected from all districts. Failure to adequately dry these seeds before storage could elevate the risk of mycotoxin contamination. Implementing management approaches targeting different fungi is essential to preserve nutritional value of groundnut seeds during storage.