In order to select pollinizer varieties of high fruit qualities with large sized and high soluble solid contents, ‘Nishimurawase’ was crossed with ‘Johongsi’ at the Pear Research Institute, National Institute of Horticultural & Herbal Science in 2000. Among these crossed seedlings, ‘00-16-121’ was selected primarily in 2007, and it was finally selected since it was worthy of not only a pollinizer but also ripen and dried persimmon and named ‘Partner’ in 2009. ‘Partner’ shows intermediate in growth habit and semi-spreading tree shape. It has plenty of male flowers and rich pollen amount with about 380 mg per one hundred flowers. The average optimum harvest time of ‘Partner’ was 144 days after full bloom and it matured around one week earlier than ‘Zenzimaru’ and three weeks later than ‘Nishimurawase’. The fruit is elliptic in shape and orange in skin color. Average fruit weight was 224 g, and soluble solids content was 18.8°Brix.

Suppression subtractive hybridization was carried out to identify resistant genes against to pear scab caused by Venturia nashicola using leaves harvested at 24 and 48 hours after inoculation into ‘93-3-98’ (highly resistant) and ‘Sweat Skin’ (highly susceptible). As a result of the ESTs analysis, nine and 14 unique genes were expressed on 24H (tester, mRNA at 24hr after inoculation of ‘93-3-98’; driver, one of ‘Sweet Skin’) and 48H (tester, mRNA at 48hr after inoculation of ‘93-3-98’; driver, one of ‘Sweet Skin’), respectively and genes related to defense or stress response were accounted for 40% (24H) and 42% (48H). Differential expressed genes classifying into PR protein family were pathogenesis-related protein 1a, major allergen Pyr c1 and allergen mal d 1 at 24H and major allergen Mal d 1.03B at 48H, respectively. Major allergen Pyr c1, F-Box/kelch-repeat protein, Flavoprotein wrbA, and hypothetical protein POPTRDRAFT_783792 are expected to closely connecting to scab resistance of pear following strongly expressed in highly resistant cv. ‘Bartlett’ and ‘93-3-98’ compared with moderately susceptible cv. ‘Gamcheonbae’, susceptible cv. ‘Wonhwang’, and highly susceptible cv. ‘Niitaka’ and ‘Sweat skin’.