Aerobiology of the Wheat Blast Pathogen: Inoculum Monitoring and Detection of Fungicide Resistance Alleles

Wheat blast, caused by the ascomycetous fungus Pyricularia oryzae Triticum lineage (PoTl), is mainly controlled fungicide use, but resistance to main groups—sterol demethylase (DMI), quinone outside (QoI), and succinate dehydrogenase inhibitors (SDHI)—has been reported in Brazil. In order rationalize inputs (e.g., choice, timing, dose-rate, spray number, mixing/alternation) for managing wheat we describe a new monitoring tool, enabling quantitative measurement of pathogen’s inoculum levels detection alleles. blast airborne spores (aerosol populations) were monitored at Londrina Paraná State, major cropping region Brazil, using an automated high-volume cyclone coupled with lab-based real-time PCR (qPCR) assay. The objectives our study as follows: (1) monitor amount PoTl conidia during 2019–2021 based on DNA detection, (2) reveal prevalence QoI resistant (QoI-R) cytochrome b alleles aerosol populations (3) determine impact weather dynamics spread was consistently detected aerosols seasons from 2019 2021, amounts varied significantly between seasons, highest 2019. High peaks also continuously off-season 2020 2021. G143A determined subset 10 positive samples frequencies varying 91% combination PCR-amplification SNP pyrosequencing. Statistically significant low correlations found pathogen variables. conclusion, this system provided prior spore