England provides the first traces of concerted activity by plant breeders, who tried to improve wheat yields. Thomas Andrew Knight (1759-18 3 8) is now generally acknowledged by contemporary breeders to have been the first, in the 1790s. Later wheat breeders credited Knight with being the first to make deliberate crosses between two different wheat plants.51
However, the most notable successes came somewhat later with the work of John LeCouteur and Patrick Shirreff (Figure 2.7). LeCouteur's work was based on selecting individual spikes of superior individuals and sowing the seeds from each spike separately. In this sense LeCouteur was not strictly a wheat breeder because he did not cross different parents and select from their progeny. But his methods were successful in identifying the variety Talevara, which was used extensively by Shirreff.52
Shirreff used the selection method, but he also began crosses. Over a period of several decades, Shirreff, at his station in Mungoswells farm, Scotland, identified several important varieties. By selection he found Shirreff's Bearded Red, Shirreff s Bearded White, Pringle, and Shirreff's Squarehead. He also used Talevara for crosses and obtained King Red Chaff White, which he considered a worthy variety.53
Selection of pure lines and additional crosses to create and select useful hybrids continued to be the output of the pre-1900 wheat breeders. Especially successful practitioners in addition to LeCouteur and Shirreff were F. Hallett54 (England), Henri
Figure 2.7 Patrick Shirreff. From Patrick Shirreff, Improvement of the Cereals (Edinburgh: William Blackwood and Sons, 1873), frontispiece.
de Vilmorin (France), Wilhelm Rimpau (Germany), Broekema (Netherlands, 1886), Hjalmer Nilsson and Herman Nilsson-Ehle (Sweden), William Saunders (Canada), William Farrer (Australia), and Liberty Hyde Bailey and W. M. Hays (United States).55 Successful as the breeders were before 1900, the rate of output of new varieties was low and their ability to explain how and why they performed their crosses was not entirely satisfactory. Science, as it gains control over a body of observations, moves from observation to explanation to prediction to control. Before 1900, wheat breeders were astute on observation and had schemes of explanation. They could not, however, do much to predict the results of their crosses and therefore had only minimal levels of control over the wheat plant's genetic resources. Mendel's theory about the flow of information from one generation to the next provided the basis for better prediction and thus better control. It is the subject of the next chapter.
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