Norsk landbruksforskning : pære - eit oversyn over historisk utvikling, produksjon, genetisk variasjon og foredling

Abstract

This study of the literature on pears and pear breeding deals with Pyrus systematics, gene centers and species development. The history and development of the European pear (Pyrus communis L.), both worldwide and within the Nordic countries, are presented. The production of pears is tabulated and production trends in different countries are discussed. Localization of production is described and the development and irnportance of Norwegian pear production are reviewed. The quality, nutritive value, and uses of pears are summerized along with rnarket trends. A brief description is given of the 10 main varieties of European pear, and their importance in different countries. The two main varieties of Oriental pear are described, and varieties of other Pyrus sp. are mentioned. The main varieties of pears in the Nordic countries are listed and the differences in variety assortment within each respective country are presented. Variety development, commercial production and development in quality and prices of the main varieties in Norway are also discussed. A brief review of the rootstocks available for pears is also given. Pyrus germ plasm has been recorded from the literature, and variations in tree charcter, fruit character, resistance and chromosome number are exemplified by species, varieties and selections. The section on breeding summarizes breeding history, breeding systems, breeding methods and breeding programs. The breeding programs at East Malling, I.N.R.A. Angers, Balsgård, USDA, Kearneysville and Harrow are described fairly accurately with regard to breeding methods and results, and other breeding stations throughout the world are mentioned.