“…The majority of the data on pear resistance to scab is based on the cultivar performance in the field, and only a few studies on a systematic and comprehensive screening of germplasm collections are available (Brewer et al., 2009; Brown, 1960; Kemp & van Dieren, 2000; Lācis et al., 2015; Postman et al., 2005). Morphological changes in leaf tissues of resistant and susceptible pear cultivars during the infection by the pathogen have been characterized, and proofs for the ontogenic and polygenic resistance have also been demonstrated (Brewer et al., 2009; Chevalier et al., 2002,2004; Chevalier, Tellier, Lespinasse, & Caffier, 2008). Studies on resistance mechanisms of pear to V .…”