DNA-based electrochemical nanobiosensor for the detection of Phytophthora palmivora (Butler) Butler, causing black pod rot in cacao (Theobroma cacao L.) pods

• Main Authors: Franco, Anthony James DM, Merca, Florinia E., Rodriguez, Myrna S., Balidion, Johnny F., Migo, Veronica P., Amalin, Divina M., Alocilja, Evangelyn C., Fernando, Lilia M.
• Format: text
• Published: Animo Repository 2019
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/726; https://animorepository.dlsu.edu.ph/context/faculty_research/article/1725/type/native/viewcontent
• Institution: De La Salle University

© 2019 Elsevier Ltd A nanobiosensor was developed for the electrochemical detection of Phytophthora palmivora, a notorious pathogen of cacao causing severe crop loss. Sandwich hybrids between two oligonucleotide probes and the genomic DNA of P. palmivora were prepared and electrochemically detected. The oligonucleotide probes were designed based on the ITS sequence of the P. palmivora field isolates. The detection of sandwich hybrids with P. palmivora genomic DNA and the selectivity of the nanobiosensor towards it compared to other cacao-associated fungal pathogens were demonstrated. The detection limit was determined to be at 0.30 ng DNA μL−1. Detection of P. palmivora DNA on cacao samples was also demonstrated. The result of the preliminary analysis on cacao pod samples shows the potential of the developed nanobiosensor for reliable and more cost-effective analysis of field samples.