Molecular detection of virus infection in Ocimum gratissimum L. in Ogoja, Cross River State, Nigeria

Viruses have been known to cause considerable yield losses in Ocimum gratissimum L., a leafy vegetable commonly known as African basil but locally referred to as “scent leaf’. The crop is cherished for its essential oil, medicinal and agricultural benefits. Virus-like symptoms on leaves causing mosaic, yellowing, leaf malformation and stunting on Ocimum gratissimum L. were observed in backyard garden in Ogoja in 2024. Molecular methods were used to detect the virus infecting the crop by testing the samples using cylindrical inclusion (CI) specific primer in reverse transcriptase-polymerase chain reaction (RT-PCR). Sequences were compared to corresponding sequences in the GenBank using the BLAST program, and the ocimum isolates showed nucleotide sequence similarities of 86 % to African cassava mosaic virus (ACMV). The findings emphasize the need for regular monitoring of viral pathogens in medicinal plants to prevent yield loss and maintain phytochemical quality.