Characterization of a wide collection of tomato (Solanum lycopersicumL.) for morpho-phenological, quality and resistance traits

Tomato (Solanum lycopersicumL.) is considered one of the leading vegetable crops worldwide and it is an important model species for plant biology, in particular for the genetic control of quantitative variation, fruit ripening processes and resistance to biotic stress. The availability of the tomato genome has enhanced the chances to unravel the genetic control of simple and complex traits that can be achieved by genome-wide association studies which exploit natural variation. Accordingly, in the present study it has been investigated a wide collection of tomato mainly including landraces (71 from Italy of which 64 from Sardinia, and 44 from all over the world) which were compared to ten cultivars and five wild-related tomato species. Three experimental trials in two years and two locations were performed and data were collected for a) phenotypic traits by both classic and precision phenotyping, b) genetic diversity by means of 19 micro-satellite markers, c) carotenoid content and d) antixenotic resistance toTuta absoluta(Meyrick). Results revealed high levels of phenotypic and genetic diversity pointing to these landraces as a valuable model to identify QTLs and genes of relevant interest. Finally, the associations detected between molecular markers and phenotypic traits indicate that our collection is suitable for future association mapping and transcriptome correlation studies in addition to breeding purposes.