Making desired traits hereditary - Elements of an epistemology of translation

The agro-economic field, its practises and institutions, discern certain traits of plants and animals that only become visible within this framework. Think of the winter hardiness of wheat, low protein/high starch content in brewing barley or the shelf life of tomatoes. It is clear that there can be no such trait without the dietary habits and the agronomic and economic systems of a given society. There is simply no shelf life without supermarket shelves. But nevertheless, once recognised, it becomes a biological property of an organism. There are some plants having fruits that stay fresh for a longer time under the given conditions of the supermarket shelve than others. To optimize organisms with respect to such desired traits and make these traits hereditary is the aim of plant breeding as well as genetic engineering. Now these practises have their own ways of defining traits. Plant breeding relies on the genetic theory of its time. In classical genetics, roughly speaking, traits are conceptualised as features that are inherited according to a certain pattern. In genetic engineering, they are features that can be manipulated by altering the genome. The practitioners in these fields of applied biology have to translate the traits defined by the agro-economic context into the trait categories based on concepts and experimental systems of the biological framework they act in. This renders traits boundary objects. I will illustrate these processes using the case of plant breeding around 1900, where early genetics and a more and more industrialized agriculture intersect. More specifically, i will take the work of Herman Nilsson-Ehle at the plant breeding station at Svalöf, Sweden as an example. I will describe the various actors and institutions and their various goals and the resulting view on the organisms they work with. I will show how the traits that are visible or accessible for the plant breeder are entrenched in an experimental and material practise and a theoretical Mendelian framework and which problems arise in the resolution of externally defined valuable traits into hereditary traits and how these efforts lead to advancements genetic theory.