A comparison of methods for the detection of Phytophthora infestans on potatoes in Mauritius

Late blight, a disease caused by oomycota, Phytophthora infestans, is greater threat to the potato crop than any other in Mauritius. This remains most challenging manage once symptoms have appeared, thus requiring rapid detection for effective management. The aim of this study was compare different methods early causal agent late blight. Conventional culture-based involved direct isolation P. infestans from infected leaves on Carrot Piece Agar (CPA), Sucrose (CSA), Commercial Potato Dextrose (CPDA), Fresh (FPDA-1 and FPDA-2), Oatmeal (OMA), Pea (PSA) Water (WA) without antibiotic supplementation. Mycelial growth agar subsequently identified using molecular techniques. A culture-independent method also attempted whereby total genomic DNA directly extracted symptomatic with mycelial followed PCR amplification ITS5/ITS4 primers sequencing. media ranked following decreasing order performance: PSA >>> CSA ~ FPDA-1 > CPA CPDA OMA, appearing within 7 days contamination. sequencing confirmed identity recovered diseased be infestans. Findings point an optimum nutritive medium recovering culturing foliar blight use antibiotics. Alternatively, can used identification during routine surveillance.