The linkage maps of the cultivated strawberry, Fragaria × ananassa (2n = 8x = 56) that have been reported to date have been developed predominantly from AFLPs, along with supplementation with transferrable microsatellite (SSR) markers. For the investigation of the inheritance of morphological characters in the cultivated strawberry and for the development of tools for marker-assisted breeding and selection, it is desirable to populate maps of the genome with an abundance of transferrable molecular markers such as microsatellites (SSRs) and gene-specific markers. Exploiting the recent release of the genome sequence of the diploid F. vesca, and the publication of an extensive number of polymorphic SSR markers for the genus Fragaria, we have extended the linkage map of the 'Redgauntlet' × 'Hapil' (RG × H) mapping population to include a further 330 loci, generated from 160 primer pairs, to create a linkage map for F. × ananassa containing 549 loci, 490 of which are transferrable SSR or gene-specific markers. The map covers 2140.3 cM in the expected 28 linkage groups for an integrated map (where one group is composed of two separate male and female maps), which represents an estimated 91% of the cultivated strawberry genome. Despite the relative saturation of the linkage map on the majority of linkage groups, regions of apparent extensive homozygosity were identified in the genomes of 'Redgauntlet' and 'Hapil' which may be indicative of allele fixation during the breeding and selection of modern F. × ananassa cultivars. The genomes of the octoploid and diploid Fragaria are largely collinear, but through comparison of mapped markers on the RG × H linkage map to their positions on the genome sequence of F. vesca, a number of inversions were identified that may have occurred before the polyploidisation event that led to the evolution of the modern octoploid strawberry species.

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This study attempted to manipulate an athlete’s facilitative or debilitative appraisal (direction; Jones, 1995) of competitive anxiety through imagery-based interventions in order to study the effects on subsequent anxiety intensity (heart rate and CSAI-2) and direction (CSAI-2D; Jones & Swain, 1992). In a within-subjects’ design, 24 experienced soccer players were relaxed via progressive relaxation audiotape and then randomly underwent an imagery-based video- and audiotaped manipulation of their appraisal of taking a hypothetical gamewinning penalty kick under either a “pressure” or “challenge” appraisal emphasis. There was no significant effect for heart rate. A repeated measures MANOVA for CSAI-2 and CSAI-2D scores revealed that for both intensity and direction scores the challenge condition produced less cognitive anxiety, less somatic anxiety, and more self-confidence (all p < .001) than the pressure situation. This finding suggests that a challenge appraisal manipulation taught by applied sport psychologists might benefit athletes’ performance.

The cultivated strawberry, Fragaria × ananassa ( Fragaria spp.) is the most economically important global soft fruit. Phytophthora cactorum , a water-borne oomycete causes economic losses in strawberry production globally. A bi-parental cross of octoploid cultivated strawberry segregating for resistance to P . cactorum , the causative agent of crown rot disease, was screened using artificial inoculation. Multiple putative resistance quantitative trait loci (QTL) were identified and mapped. Three major effect QTL ( FaRPc6C , FaRPc6D and FaRPc7D ) explained 37% of the variation observed. There were no epistatic interactions detected between the three major QTLs. Testing a subset of the mapping population progeny against a range of P. cactorum isolates revealed no significant interaction ( p = 0.0593). However, some lines showed higher susceptibility than predicted, indicating that additional undetected factors may affect the expression of some quantitative resistance loci. Using historic crown rot disease score data from strawberry accessions, a preliminary genome-wide association study (GWAS) of 114 individuals revealed an additional locus associated with resistance to P . cactorum . Mining of the Fragaria vesca Hawaii 4 v1.1 genome revealed candidate resistance genes in the QTL regions.

Over the last two centuries, breeders have drastically modified the fruit quality of strawberries through artificial selection. However, there remains significant variation in quality across germplasm with scope for further improvements to be made. We reported extensive phenotyping of fruit quality and yield traits in a multi-parental strawberry population to allow genomic prediction and quantitative trait nucleotide (QTN) identification, thereby enabling the description of genetic architecture to inform the efficacy of implementing advanced breeding strategies. A negative relationship (r = −0.21) between total soluble sugar content and class one yield was identified, indicating a trade-off between these two essential traits. This result highlighted an established dilemma for strawberry breeders and a need to uncouple the relationship, particularly under June-bearing, protected production systems comparable to this study. A large effect of quantitative trait nucleotide was associated with perceived acidity and pH whereas multiple loci were associated with firmness. Therefore, we recommended the implementation of both marker assisted selection (MAS) and genomic prediction to capture the observed variation respectively. Furthermore, we identified a large effect locus associated with a 10% increase in the number of class one fruit and a further 10 QTN which, when combined, are associated with a 27% increase in the number of marketable strawberries. Ultimately, our results suggested that the best method to improve strawberry yield is through selecting parental lines based upon the number of marketable fruits produced per plant. Not only were strawberry number metrics less influenced by environmental fluctuations, but they had a larger additive genetic component when compared with mass traits. As such, selecting using “number” traits should lead to faster genetic gain.