Defining strawberry shape uniformity using 3D imaging and genetic mapping

Strawberry shape uniformity is a complex trait, influenced by multiple genetic and environmental components. To complicate matters further, the phenotypic assessment of strawberry uniformity is confounded by the difficulty of quantifying geometric parameters ‘by eye’ and variation between assessors. An in-depth genetic analysis of strawberry uniformity has not been undertaken to date, due to the lack of accurate and objective data. Nonetheless, uniformity remains one of the most important fruit quality selection criteria for the development of a new variety. In this study, a 3D-imaging approach was developed to characterise berry shape uniformity. We show that circularity of the maximum circumference had the closest predictive relationship with the manual uniformity score. Combining five or six automated metrics provided the best predictive model, indicating that human assessment of uniformity is highly complex. Furthermore, visual assessment of strawberry fruit quality in a multi-parental QTL mapping population has allowed the identification of genetic components controlling uniformity. A “regular shape” QTL was identified and found to be associated with three uniformity metrics. The QTL was present across a wide array of germplasm, indicating a potential candidate for marker-assisted breeding, while the potential to implement genomic selection is explored. A greater understanding of berry uniformity has been achieved through the study of the relative impact of automated metrics on human perceived uniformity. Furthermore, the comprehensive definition of strawberry shape uniformity using 3D imaging tools has allowed precision phenotyping, which has improved the accuracy of trait quantification and unlocked the ability to accurately select for uniform berries

Genetic dissection of fruit quality traits in the octoploid cultivated strawberry highlights the role of homoeo-QTL in their control

Fruit quality traits are major breeding targets in the Rosaceae. Several of the major Rosaceae species are current or ancient polyploids. To dissect the inheritance of fruit quality traits in polyploid fleshy fruit species, we used a cultivated strawberry segregating population comprising a 213 full-sibling F1 progeny from a cross between the variety ‘Capitola’ and the genotype ‘CF1116’. We previously developed the most comprehensive strawberry linkage map, which displays seven homoeology groups (HG), including each four homoeology linkage groups (Genetics 179:2045–2060, 2008). The map was used to identify quantitative trait loci (QTL) for 19 fruit traits related to fruit development, texture, colour, anthocyanin, sugar and organic acid contents. Analyses were carried out over two or three successive years on field-grown plants. QTL were detected for all the analysed traits. Because strawberry is an octopolyploid species, QTL controlling a given trait and located at orthologous positions on different homoeologous linkage groups within one HG are considered as homoeo-QTL. We found that, for various traits, about one-fourth of QTL were putative homoeo-QTL and were localised on two linkage groups. Several homoeo-QTL could be detected the same year, suggesting that several copies of the gene underlying the QTL are functional. The detection of some other homoeo-QTL was year-dependent. Therefore, changes in allelic expression could take place in response to environmental changes. We believe that, in strawberry as in other polyploid fruit species, the mechanisms unravelled in the present study may play a crucial role in the variations of fruit quality

Confronting Inauthenticity – Utopias of David Bowie

Bowie consists of twenty-one short chapters that function as a collection of conceptual fragments. Bowie's artistic work already provides a series of different periods each with its own stock of identities which could easily be comprised into different sections of this book according to, as Critchley calls them, illusions he inhabited, both musically and aesthetically. Although a sense of linearity is present, as the author tends to give an overview of albums and his own fan sensibilities, dividing the book according to Bowie's own artistic eras is avoided. The division into twenty-one chapters is much closer to breaking Bowie's work into conceptual categories that are present throughout his career and are related to questions of identity, sexuality and desire or sometimes even Bowie's own life in the background of it all. Still, as the author notes at the very beginning of the book – it is important not to conflate Bowie as a persona of popular music with his work. It is a popular approach in music journalism and production of music biographies to somehow look behind the performance in search of traumas that might have provoked an artist to perform in a specific mode. This is in its own a desire of authenticity always present with popular music that Critchley seeks to deconstruct in order to give more layers to Bowie's music, or as he is approaching it – poetry

Variation of genetic dissection of seasonal vs recurrent flowering according to year in the cultivated strawberry

International audienc

Use of a reference octoploid map for detecting homoeologous QTLs

International audienc

Variation of genetic dissection of seasonal vs recurrent flowering according to year in the cultivated strawberry

International audienc

Use of a reference octoploid map for detecting homoeologous QTLs

International audienc

Comparative quantitative trait locus (QTL) suggests polyploidization in Fragaria led to different genetic keys for recurrent flowering in Fragaria

National audienc

Analyse du génome du fraisier cultivé octoploïde

National audienc

Metabolic profiling by proton NMR for genetic study of fruit quality

International audienc