Genetic mapping of pear scab resistant gene Rvn1

Pear scab is the most serious disease affecting Japanese pear production, causing significant economic losses. To develop scab-resistant cultivars, the scab resistance gene derived from the Japanese pear 'Kinchaku' was narrowed down through fine mapping using 4,297 seedlings from 23 populations. RNA-seq was performed to identify the pear scab resistance gene, Rvn1. The resistant cultivar Hoshiakari, a descendant of Kinchaku, and the susceptible cultivar Kosui were used for inoculation with isolate HA38 (race 3). Leaf samples were meticulously collected before inoculation, as well as at 2 days and 5 days post-inoculation, to monitor gene expression changes and understand the resistance mechanism.