A novel PCR-DNA probe for the detection of fumonisin-producing Fusarium species from major food crops grown in southern India

Abstract

Fumonisins are a group of 20 chemically related toxic fungal metabolites mainly produced by Fusarium verticillioides and Fusarium proliferatum. In this study, attempt has been made to develop rapid detection of fumonisin-producing Fusarium species from freshly harvested rice and finger millet by novel and sensitive polymerase chain reaction-deoxyribonucleic acid (PCR-DNA) probe. One set of oligonucleotide primers was designed targeting FUM13 gene involved in fumonisin biosynthesis and PCR-DNA probe was developed for dot-blot hybridization assay. The sensitivity of developed PCR-DNA probe was determined; it could detect 10 pg genomic DNA and 1 pg of purified PCR product. To determine the practical usefulness, the developed PCR-DNA probe was evaluated onto the rice grains that were artificially inoculated with toxigenic fungal spores. Sensitivity of the developed probe was found to be 1 × 106 CFU per gram of the rice sample using dot-blot hybridization assay. The specificity of the DNA probe was validated by testing against an array of Fusarium, including Gibberella zeae clade and other fungal strains. All PCR-DNA probe results were further cross-checked with conventional high performance thin layer chromatography (HPTLC) method. PCR-DNA probe results were equivocally matched with the HPTLC method. The novel PCR-DNA probe developed in this study may find application in rapid detection of fumonisin-producing Fusarium isolates from contaminated cereal grains. © 2012 Copyright 2012 Mycological Society of China.