title: The plant breeding industry after pure line theory: Lessons from the National Institute of Agricultural Botany.
abstract: In the early twentieth century, Wilhelm Johannsen proposed his pure line theory and the genotype/phenotype distinction, work that is prized as one of the most important founding contributions to genetics and Mendelian plant breeding. Most historians have already concluded that pure line theory did not change breeding practices directly. Instead, breeding became more orderly as a consequence of pure line theory, which structured breeding programmes and eliminated external heritable influences. This incremental change then explains how and why the large multi-national seed companies that we know today were created; pure lines invited standardisation and economies of scale that the latter were designed to exploit. Rather than focus on breeding practice, this paper examines the plant varietal market itself. It focusses upon work conducted by the National Institute of Agricultural Botany (NIAB) during the interwar years, and in doing so demonstrates that, on the contrary, the pure line was actually only partially accepted by the industry. Moreover, claims that contradicted the logic of the pure line were not merely tolerated by the agricultural geneticists affiliated with NIAB, but were acknowledged and legitimised by them. The history of how and why the plant breeding industry was transformed remains to be written.
authors.affiliation: School of Philosophy, Religion and History of Science, University of Leeds, Leeds, W Yorkshire LS2 9JT, UK. Electronic address: Ph09djb@leeds.ac.uk.
authors.forename: Dominic
authors.initials: D
authors.lastname: Berry
mesh_terms: D000383:Agriculture / Q000266:history*; D001901:Botany / Q000266:history*; D001947:Breeding / Q000266:history*; D004739:England; D049673:History, 20th Century; D010944:Plants / Q000235:genetics*
keywords: Agriculture; Britain; Genetics; Plant breeding; Pure line; Wilhelm Johannsen