Diversity of thermal aptitude of Middle Eastern and Mediterranean <i>Puccinia striiformis</i> f. sp. <i>tritici</i> isolates from different altitude zones

Abstract The worldwide spread of wheat yellow rust lineage PstS1/S2 adapted to higher temperatures prompted us investigate how diverse temperature responses this are in the Middle East, where diversity was previously observed within for pathotypes and genotypes. Here we highlight response a population. Twenty‐six isolates from eight countries different altitudes, which were tested under four combinations cold warm incubation postincubation conditions, showed infection efficiency (IE) latency period (LP). IE various ranged 5.8% 13.7% (5°C) 0.04% 1% (20°C) temperatures. LP varied 10.2 days 4.43 incubation. same country could differ by 2 days. Significant differences thermal aptitudes between countries. not related altitude origin on whole; however, trade‐off low (&lt;400 m) regime. We aptitude belonging lineage. Understanding Pst among geographically distant clonal may help identify geographic range pathogens also improve forecast models or breeding programmes.