What kind of genetic mapping approach will be suitable for mapping metabolites (health beneficial) in a diverse set of tomato varieties; Association Mapping?
If you have a genotyped diverse set of tomato varieties, then you need to use association mapping. The mapping approach doesn't really matter if it is used with metabolites or morphological data.
Association mapping would be straight forward approach when you have diverse set while you may choose to use bi-parental mapping if you have identified contrasting parents to cross.