In the 1920s and early 1930s, American grain producers developed a practical way to produce hybrid wheat. Seeds of “double hybrids” can be produced at an affordable price for farmers. Farmers can therefore reap the benefits of inbreeding followed by the targeted crossing of grain lines, leading to increased potency and yield of the hybrid offspring. Dr. Duvick describes the emergence of hybrid wheat in the article “Biotechnology in the 1930s: The Development of Hybrid Corn” in the January 2001 issue of Nature Reviews / Genetics. He claims in the article that the technology was introduced even though wheat growers and other scientists did not understand (and still do not understand) the genetic principles of hybrid potency, one of the main reasons for the increased productivity of hybrid wheat.
The introduction of hybrids also allowed for the economic protection of intellectual property in corn exploration for the first time. Farmers who purchased the seed could not maintain or re-create the hybrid and therefore had to buy seed from corn seed companies every year if they wanted to maintain the yield advantage of corn hybrids. This led to a profitable plant improvement industry. Numerous “corn seed companies” soon accounted for much of the selection and virtually all hybrid corn production and sales in the United States (Figure 1). Corn Belt farmers readily adopted this new technology, and within a few years, most of the area was cultivated with corn hybrids (Figure 2). Maize productivity began to increase immediately and continues to increase, mainly due to annual improvements in hybrid genetics (Figure 3). As with any new business, new businesses had questions and problems. Below are excerpts from two letters initiated by the president of one of these hybrid corns. Both letters illustrate some of the dilemmas faced by the then president of the company.