Kiwifruit

Abstract

Kiwifruit are a national icon in New Zealand. Nowhere else in the world do kiwifruit appear on postage stamps, can you buy kiwifruit-shaped soft toys, and can tourists take a drive in a kiwi-kart through an entire kiwifruit theme park. Yet kiwifruit are not native to New Zealand. The centre of diversity for the genus Actinidia is South Eastern Asia, in particular the Yangtze Valley of China. Kiwifruit’s association with New Zealand only started in the early twentieth century when a missionary returning from China brought a small handful of seed to New Zealand. Several cultivars were selected by amateur horticulturalists in the 1930s and the New Zealand export industry was developed around fruit of the A. deliciosa cultivar Hayward in the 1960s (Ferguson et al. 1996). During the 1980s, breeding programs were established in New Zealand using additional germplasm imported from China. The first internationally successful product from the New Zealand breeding program was a large gold-fruited A. chinensis cultivar, released commercially in 1998 as ZESPRI™ GOLD. New products currently being released are sweet-flavored A. arguta selections and further A. deliciosa and A. chinensis selections that are defined by specific market- and production-related targets (Ferguson et al. 1996; Seal 2003). It is not surprising, given its history of commercial development in New Zealand, that the drive to apply biotechnology to kiwifruit is also being driven by research within New Zealand (n.b. kiwifruit will be used here as a generic term to describe all species of Actinidia).