Peronosclerospora philippinensis (Philippine corn downy mildew): predicting plant disease emergence and distribution

Abstract

Peronosclerospora philippinensis, or the Philippine corn downy mildew, is an obligate biotrophic pathogen of the Phylum Oomycota. The organism is tagged as the most destructive pathogen of maize worldwide, and recently, there have been a few reports on the re-occurrence of the pathogen from the past decade. Disease control and mitigation through chemical agents have been the current practice; however, it appears that the pathogen is influenced by environmental factors that drive re-emergence. Presented herein is an attempt to predict the potential geographical distribution of P. philippinensis in the Philippines. Two changing climate scenarios were generated, and data suggested a probable expansion of the pathogen to the Southern Tagalog region and some areas in the Visayas region, particularly on Negros Island. Further, the mean diurnal range for the current climate and precipitation in the driest month for the predicted scenarios appeared as the most contributory bioclimatic variables affecting distribution. Generated data suggest a call for a proactive response to the potential disease breakthrough of the Philippine corn downy mildew