Genetic Diversity and Erosion in Berries

Abstract

Fragaria (strawberry; Rosaceae), Rubus (brambles: raspberry and blackberry; Rosaceae), and Vaccinium (blueberry, cranberry and lingonberry; Ericaceae) are among the most important berry crop genera worldwide. Berry fruits are rich in vitamin C, cellulose, and pectin, and produce anthocyanins which have important therapeutic values, including antitumor, antiulcer, antioxidant, and antiinflammatory activities. As in other crops, biodiversity of berry crops decreased dramatically at the species and intraspecific levels, leading to genetic erosion due to complex process involving both human and environmental drivers. Genetic erosion occurs when old varieties in farmers' fields are replaced by newer ones. Conservation of genetic resources is of prime importance to prevent genetic erosion. Efforts are being made to conserve the biodiversity of berries across Europe and North America. Utilization of diverse, locally adapted germplasm is required for the future viability of berry production. There is a pressing need to develop reliable methods for conserving, maintaining, and identifying berry germplasm and for assessing genetic biodiversity for practical breeding purposes and proprietary-rights protection. The introduction of molecular biology techniques, such as DNA-based markers, allows direct comparison of different genetic material independent of environmental influences. This paper presents the progress indepth of various aspects of molecular diversity analyses in wild berry species and cultivars collected from Canada, Europe, and USA. Different molecular markers detected a sufficient degree of polymorphism to differentiate among wild clones and cultivars, making these technologies valuable for cultivar identification and for the more efficient choice of parents in berry breeding programs. The chapter describes in-depth the progress of various aspects of berry crop diversity, erosion, and their characterization at molecular and chemical levels, and on the employment of molecular markers for the assessment of genetic diversity, relatedness and population structure in berry crop germplasm.