A lot of people think that domestication and plant breeding has led to genetic erosion, including loss of nutritional value, especially in tomato. A recent study looked at the diversity dynamics of greenhouse tomato varieties in NW Europe over the last seven decades. Lo and behold, the study provided compelling evidence that plant breeding has in fact increased! The diversity of tomato varieties, a whopping eight-fold since the 1960s. Conclusion: the concern that modern plant breeding is decreasing diversity among varieties, is not at all supported by scientific evidence, at least for greenhouse grown tomatoes in NW Europe. In contrast, a tremendous increase in diversity was observed, both at the genotypic and phenotypic level of greenhouse grown tomatoes.
A recent paper in Nature Biotechnology on de novo domestication of tomato voiced the general belief that “breeding of crops over millennia for yield and productivity has led to reduced genetic diversity. As a result, beneficial traits of wild species, such as disease resistance and stress tolerance, have been lost. Despite the increases in yield conferred by domestication, the breeding focus on yield has been accompanied by a loss of genetic diversity and reduced nutritional value and taste. To try and find more data on this assumption, Wageningen researcher Henk Schouten and his colleagues looked at the diversity dynamics of greenhouse tomato varieties in NW Europe over the last seven decades.