Identification and Sequencing of aflP (omt) and aflD (Nor-1) Genes from Aspergillus flavus Species isolated from Maize (Zea mays L.), Obtained Across Abuja, Nigeria

Abstract

This study aims to examine aflD (Nor-1) and aflP (omt) genes that could be present in species of Aspergillus flavus isolated from varieties of maize seeds obtained across Abuja, Nigeria, utilizing the PCR method and Sanger sequencing method. The DNA extraction of16 isolates (14 were procured maize varieties and 2 known aflatoxin infected varieties of yellow and white maize from the laboratory to serve as positive control) was carried out with Zymo, D6005 DNA extraction kit. All 16 A. flavus isolates were tested for amplification of Aflatoxin genes with oligonucleotide primers (FwOmt-1:5’, RvOmt-1:5’, FwNor-1: 5′, and Rv Nor-1: 5′). The PCR analysis was carried out with a DreamTaq Green PCR Master Mix (2x). The sanger sequencing was carried out using ExoSAP-IT™ Express PCR Product Cleanup Sequencing Kit. The findings of this study showed that all A. flavus isolated from the various maize varieties had the presence of NOR (afl D) gene except for the A. flavus isolated from Maize-Samaz 15, Maize-Oba super 39 and Maize-Oba super 6 (UNIAbuja). In addition, Maize-DK 777, Maize-Samaz 52 (Abaji) and Maize-Samaz 37 varieties had the OMT (aflP) gene. This study has demonstrated that an Aspergillus flavus attack may either be accompanied with aflatoxin production or not, with the Maize-Oba super 39, Maize-Samaz 15 and Maize-Oba super 6 (UNIAbuja) although infected with A. flavus they had no aflD and aflP gene present in them. In addition, this study revealed that the maize varieties across Abuja were prone to A. flavus contamination which have tendency to produce aflatoxin.