Appendix II-A 
A Case Study of Wheat 
wheat is a major food staple in the diet of a large 
percentage of the world’s population. Wheat grain in 
the United States is used almost exclusively for 
human consumption, although temporary localized 
oversupply may result in some wheat feeding to live- 
stock. 
Attempts to improve wheat plant populations by 
selection began several thousand years ago. The de- 
sirable attributes selected included the ability to 
withstand severe environmental stresses such as 
heat, cold, and drought and the stability of the seed 
head (which tends to disarticulate in wild forms). 
Wheat seeds moved from country to country 
along with explorers and colonists. New varieties 
played major roles in the establishment of many 
productive wheat cultures— e.g., the Mennonite set- 
tlers introduced hard red winter (Turkey Red) wheat 
into the Kansas area from Russia in the late 19th 
century. And two private breeders— E. G. Clark of 
Sedgenick, Kans., and Danne of Elreno, Okla.— de- 
veloped varieties that set new levels of productivity 
and straw strength in hard winter wheats which 
were sought by millers for their excellent flour 
recovery. 
Breeding programs expanded during the first half 
of the 20th century. At first, the U.S. Department of 
Agriculture (USDA) played a lead role; but the 
emergence of the Land Grant System and the estab- 
lishment of the State experiment station concept 
prompted individual States to launch breeding pro- 
grams designed to address the particular production 
problems faced by farmers within their respective 
boundaries. 
As the State experiment stations began to assume 
more responsibility, USDA programs and personnel 
began to concentrate in central locations to assemble 
the optimal number of personnel for the greatest in- 
teraction and productive output. If the present trend 
continues, there will be virtually no USDA scientists 
engaged in actual wheat breeding. Instead they will 
have assumed the roles of basic researchers and re- 
gional coordinators supplying information to the 
public and private breeders. 
Disease and insect resistance have been the pri- 
mary breeding goals of many programs. The dramat- 
ic losses associated with severe pest problems have 
focused the attention of producers, researchers, and 
legislators on these areas of need. Other traditional 
breeding objectives have included improved use 
properties, tolerance to environmental stresses such 
as cold, wheat, wind dessication, and excessi\e mois- 
ture, and inherent yield capacity in the absence of 
significant production limitations. 
The quality of wheat’s end products has been 
impro\ed significantly through breeding. Varieties 
have been tailored to meet the demands of \ arious 
industries. The bread bakeries needed a higher pi’o- 
tein and more gluten strength to make a lighter, 
larger loaf, while the cookie producer needed a low - 
protein flour w ith desirable dough-spreading prop- 
erties. 
Wheat productivity and management 
The pattern of wheat productiv ity (yield |)er acre) 
in developed countries is remarkably similar. When 
yields are plotted o\er the centuries, there is a long 
period of barely perceptible increases in yield, from 
the time of first records of production to the end of 
the first third of this century (the period of 1925-35). 
Since around 1935, yield has increased sharply. Re- 
cent data suggest that yield increases may he U'\ (>ling 
off. Why increases have been so substantial after 
generations of little success, is a complex ciuestion in- 
voh'ing genetic resources, economic de\ ('lo|)m('nt. 
social interaction, and ado|)tion of mechanical and 
biological inno\ ations. 
Lintil recently, the U.S. commercial seed com|)a- 
nies, with one or two exceptions, ha\e not been in- 
terested in wheat breeding programs as a prolitmak- 
ing venture. Since wheat has a perfect flower and 
can fertilize itself, the fai nier can |)urchase seed ol a 
new' variety and reproduce it from generation to 
generation, llowexer, the di.scxncrv of cyto|)lasmic 
male sterility and nuclear restorer genes has stim- 
ulated industry interest in the possibility of devel- 
oping hybrid wheat. The farmer would purchase the 
hybrid seed each yc^ar: the inl)red lines used to make 
the hybrid would he the exclusive |)ropertv ol the 
originating company. .Although |)rogress h.is been 
good, problems (rxisi with tin* sterililv and restorer 
systems, the ability to produce* ade(|uate amounts ol 
hybrid seed, and the id(*ntification ol economie levels 
of hybrid vigor. The next 5 years should reveal live 
potential for success in hybrid w heal. 
Several milestone’s e)f |)re)gre*ss have* he*e*n se*l m 
wheat. Meld has rise*n elramatie allv (.e*ne*lie- preile*e - 
tion against |)ests anel e)the*r ha/arels has he*e*n a m.i 
jor contiihute)!' lee ine ie*ase*el yie’lels In .lelelilieen re* 
cent advances using se*mielwarf ge*ne*s have* he*e*n ,is 
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