Present status and prospects of strawberry breeding and cropping type in northern Japan

As northern Japan (the Hokkaido and Tohoku districts) encompasses two different strawberry production regions, cold regions (Hokkaido, Akita and Yamagata Prefecture) and warmer regions (the Pacific coast of Aomori, Miyagi, and Fukushima Prefecture), during winter, breeding programs for late June-bearers and early June-bearers have been conducted. Cultivars with a relatively long dormant period such as 'Morioka-16' were released as late June-bearers. 'Fukuharuka', 'Fukuayaka', and 'Moikko' were bred as early June-bearers. 'Kitanokagayaki' and 'Belle Rouge' are grown in open field cultures in Hokkaido and Akita Prefecture, in semi-forced cultures in Hokkaido, Iwate and Akita Prefecture, and are late raised in Akita Prefecture. On the other hand, 'Mouikko', 'Fukuharuka' and 'Fukuayaka' are grown mainly using forced culture at the Pacific coast in Miyagi and Fukushima Prefecture. Though the area of strawberry cultivation and the amount of strawberry production in northern Japan occupy only 14% of the total areas and 8% of the total productions, respectively, its importance as a strawberry production region is high because the summer to autumn production which runs short in Japan is expected to increase in view of the region's cool climate conditions. For these reasons, the ever-bearers such as 'HS-138', 'Kiminohitomi', 'Natsuakari' and 'Summer Candy', have been bred. The strategy for summer and autumn production has also been spotlighted by developing a new cropping system (a short-day treatment carried out in nursery plants for around 30 days) for a June-bearer such as 'Kitanokagayaki'. As a new mode of cooperation, a study group intended to develop information exchange among all those involved with strawberry research, production, extension, and industries has recently been organized in northern Japan.