Bologna University’s plum breeding program

Bologna University’s plum breeding program at the Department of Agricultural Sciences has developed in two main phases. Following its inception in the 1970s, it released the European cultivars. ‘Sugar Top’ and ‘Prugna 29’, and the Japanese cultivars ‘Black Glow’ and ‘Black Sunrise’. These efforts led in 2008 to a joint venture with private-industry partner New Plant, a consortium of Apo Conerpo, Apofruit, and Orogel Fresco, and to a strategy change. The shift in focus was, and is still, designed to develop novel cultivars of high-quality traits, from field performance through postharvest handling and retail, in line with emerging market demands. The specific targets for Japanese plum include large fruit size, enhanced firmness for postharvest sorting, storage and transport, upgraded flavor and taste properties like texture, juiciness, and sweet/sour balance, and distinctive red flesh coloring in response to consumer preferences. The goals for European plum mostly involve upgrading field performance and consumer-appealing fruit flavor properties. Common to both tacks is developing a product line of cultivars with similar performance, including on-tree retention of ripeness for flexible picking schedules and fruit quality characteristics that cover a broader seasonal picking calendar to ensure continuous market supply. The initial screening of some 2500 seedlings has so far identified 30 Japanese and 10 European selections that potentially match the specific and common goals for each species. In 2015, Bologna University filed an application for the grant of EU plant breeder’s rights for the new Japanese plum cultivar ‘SU1_UNIBO’ and then licensed the commercial rights to New Plant for its distribution in Europe.