Suchergebnisse

[EN] Tomato flavour is an important goal for breeders. Volatile organic compounds (VOCs) are major determinants of tomato flavour. Although most tomato varieties for fresh market are F1 hybrids, most studies on the genetic control of flavour-related traits are performed on lines. We quantified 46 VOCs in a panel of 121 small fruited lines and in a test cross panel of 165 hybrids (the previous panel plus 44 elite cherry tomato lines crossed with a common line). High and consistent heritabilities were assessed for most VOCs in the two panels, and 65% of VOC contents were strongly correlated between lines and hybrids. Additivity was observed for most VOCs. We performed genome wide association studies (GWAS) on the two panels separately, along with a third GWAS on the test cross subset carrying only F1 hybrids corresponding to the line panel. We identified 205, 183 and 138 associations, respectively. We identified numerous overlapping associations for VOCs belonging to the same metabolic pathway within each panel; we focused on seven chromosome regions with clusters of associations simultaneously involved in several key VOCs for tomato aroma. The study highlighted the benefit of testcross panels to create tasty F1 hybrid varieties. ; This research was funded by the CIFRE project Qualhytom, grant number 2018/1239, the ANR project TomEpiSet, grant number ANR-16-CE20-0014 and European Union's Horizon 2020 research and innovation programme, HARNESSTOM, grant number No. 101000716. ; Bineau, E.; Rambla Nebot, JL.; Priego-Cubero, S.; Hereil, A.; Bitton, F.; Plissonneau, C.; Granell Richart, A. (2021). Breeding Tomato Hybrids for Flavour: Comparison of GWAS Results Obtained on Lines and F1 Hybrids. Genes. 12(9):1-20. https://doi.org/10.3390/genes12091443 ; S ; 1 ; 20 ; 12 ; 9

[EN] Amblyseius swirskii is a predatory mite widely used for the control of very important pest species, such as whiteflies and thrips, in organic farming and conventional agriculture. However, this species cannot establish on tomato crops, probably due to the toxic effects of plant trichomes and their exudates. We evaluated tomato plants for effects on: a) A. swirskii preference mediated by plant volatiles, b) A. swirskii development, predation capacity and reproductive performance, c) the dispersal and survival of mites as affected by stem trichomes, and d) mite survival as a function of secondary metabolites secreted by tomato trichomes. The results showed that A. swirskii mites which gained experience foraging on tomato plants, tend to avoid them. The survival of A. swirskii eggs and juveniles on tomato leaves was not different from that on sweet pepper. However, adult survival was significantly lower when tested on whole plants. This was ostensibly due to the impact of trichomes and their secondary metabolites that are abundant on the stems and which negatively impacted mite dispersal on the plant. Among the secondary metabolites detected in tomato trichomes, the strongest negative effects were associated with acyl sugars. Acyl sugars were highly toxic to the mites and also, physically accumulated on their bodies after walking on tomato stems. Altogether, our results reveal why A. swirskii is not an efficient biocontrol agent on tomato crops. ; This work was funded by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 641456. JGC was supported by the Spanish Ministry of Economy and Competitiveness, Ramon y Cajal Program (RYC-2013-13834). JLR was supported by the Spanish Ministry of Economy and Competitiveness through a "Juan de la Cierva-Formacion" grant (FJCI-2016-28601). Mass spectrometric determinations were carried out at Servei Central d'Instrumentacio Cientifica (SCIC) from Universitat Jaume I. ; Paspati, A.; Rambla Nebot, JL.; ...