Genetic Diversity of Red Raspberry Varieties throughout the-World

Abstract

<jats:p>Pedigrees of 137 red raspberry (<jats:italic>Rubus idaeus</jats:italic> L.) varieties released throughout the world since 1960 were used to calculate: 1) the genetic contribution of founding clones to these varieties; 2) genetic relatedness among them; and 3) their inbreeding coefficients. Fifty founding clones contributed to the pedigrees of these varieties with a mean genetic contribution ranging from &lt;0.1% to 21%. Varieties were clustered according to the genetic contribution into groups strongly related to geographical origin. Varieties developed in the former USSR and derived from `Novost Kuzmina' formed a distinct cluster. The remaining varieties were clustered in groups based mainly on whether they were of North American or European origin. Varieties were clustered also on the basis of Wright's coefficient of relationship-a measure of genetic relatedness. Cluster groups were related to their geographical origin and the varieties within the groups could be traced to similar intermediate parents. Inbreeding coefficients ranged from 0.0 to 0.625 and were related, in part, to the numbers of generations of controlled hybridization from common ancestors. The British group, with the largest number of generations of breeding, had a low mean inbreeding coefficient, indicating that inbreeding can be minimized with attention to the mating system. Strategies are suggested for maintaining and increasing the genetic diversity in the world's red raspberry breeding populations.</jats:p>

Saturated linkage map construction in Rubus idaeus using genotyping by sequencing and genome-independent imputation

“…Despite the calculation of relatively low inbreeding coefficients for both ‘Heritage’ and ‘Tulameen’ (0.094 and 0.069 respectively) by Dale et al (1993) [49], in this investigation we observed almost twice the level of heterozygous SNPs in the genome of ’Heritage’ than in the genome of ‘Tulameen’. Relatively high levels of genome differentiation and heterozygosity is a feature of red raspberry germplasm, despite the majority of modern varieties being derived from a narrow genetic base [49].…”

Construction of black (Rubus occidentalis) and red (R. idaeus) raspberry linkage maps and their comparison to the genomes of strawberry, apple, and peach

“…Using methods described by Falconer and Mackay (1996), we calculated the inbreeding coefficient for S1 to be 0.35, indicating that 35% of alleles at a locus are identical by descent, resulting in a sparsely populated S1 genetic map. The degree of inbreeding in S1 is higher than the average of 21% reported for raspberry cultivars (Dale et al 1993), and the 0-25% reported in both blackberry (Rubus subgenus Rubus) (Stafne and Clark 2004) and almond (Prunus dulcis) cultivars (Lansari et al 1994). The parent 96395S1 has a pedigree dominated by black raspberry (R. occidentalis); however it was derived from crosses of black raspberry with red raspberry 'Burnethholm' with the intention to introgress spinelessness from this cultivar.…”

The construction of a genetic linkage map of red raspberry (Rubus idaeus subsp. idaeus) based on AFLPs, genomic-SSR and EST-SSR markers

“…Five parent cultivars dominate the ancestry of red raspberry; 'Lloyd George' and 'Pynes Royal' entirely derived from the European subspecies and 'Preussen', 'Cuthbert' and 'Newburgh' derived from both European and North American subspecies. Domestication has resulted in a reduction of both morphological and genetic diversity in red raspberry (Haskell 1960;Jennings 1988) with modern cultivars being genetically similar (Dale et al 1993;Graham and McNicol 1995).…”