Field Evaluation of Raspberry Cultivars in North Dakota

Raspberry has been widely used for fresh consumption and processed products in the world. Recently there has been increasing interest in raspberry production in the northern Great Plains due to its high soluble fiber, vitamins, and minerals. In North Dakota, harsh winter conditions often result in considerable winter injury of many floricane raspberries and a short growing season will result a lower yield because a large percentage of fruits remain immature before the fall frost. In this study, ten floricane cultivars (‘Prelude’, ‘Boyne’, ‘Killarney’, ‘Nova’, ‘Meeker’, ‘Latham’, ‘Encore’, ‘Amthyst’, ‘Royalty’, and ‘Mac Black’) and nine primocane cultivars (‘Polana’, ‘Autumn Bliss’, ‘Autumn Britten’, ‘BP-1’, ‘Himbo-Top’, ‘Joan J’, ‘Caroline’, ‘Heritage’, and ‘Anne’) that were reported to have good hardiness and fruit quality are being field evaluated in North Dakota. The experiment is a randomized complete block design (RCBD). Each block contains 4-6 plants per cultivar and replicated 4-6 times (blocks). The planting spacing is 9’ × 5’ and the “V”-shape trellis system was used. One year result (2014) indicated that seven floricane cultivars survived the winters with various degrees of winter injury. ‘Prelude’, ‘Boyne’, ‘Killarney’, ‘Amthyst’, ‘Latham’, and ‘Nova’ showed no or very minor winter damage. ‘Encore’ showed some dieback. Primocanes of ‘Polana’ were vigorous and produced fruits in early August to early October. ‘Prelude’ is the earliest ripening cultivar with 5% of fruits being harvested in July 7, followed by ‘Killarney’, ‘Boyne’, ‘Nova’, and ‘Encore’. Polana had the longest harvest duration (62d). ‘Polana’, ‘Killarney’, and ‘Nova’ produced the largest fruit size. Various soluble sugar contents (SSC), firmness, and flavor were observed in cultivars. Winter hardiness, fruit quality, and resistance to major pests will be evaluated in the following years.