Contribution of Genetic Improvement to Recent Wheat Yield Increases in the USA1
- A. M. Feyerherm,
- G. M. Paulsen and
- J. L. Sebaugh2
Genetic yield potential of wheat (Triticum aestivum L. and T. turgidum L. var. durum) has increased markedly during recent decades, but its impact on production has not been well documented. Studies were conducted to measure the effect of genetic improvements from 1954 through 1979 on growers' yields of wheat in states where each major class is grown. Differential yielding ability (DYA) values were calculated for popular cultivars from a broad data base of performance trial yields and weighted by the mix of cultivars in production in each state. Yield increases attributed to changing cultivar mixes in spring wheat states ranged from 268 kg ha−1 in Montana to 550 kg ha−1 in Minnesota. Increases in the hard red winter wheat region were greatest in Nebraska (416 kg ha−1), Oklahoma (368 kg ha−1), and Kansas (348 kg ha−1) and were smallest in Texas (233 kg ha−1), Colorado (228 kg ha−1), and Montana (193 kg ha-'). Soft wheat yield increases ranged from 739 to 854 kg ha−1 in Corn Belt states and 734 kg ha−1 in Washington State. We concluded that the impact of genetic improvement was inversely related to environmental constraints, that substantial yield improvement in unfavorable environments requires greater emphasis on stress resistance, and that no slowing of the rate of yield improvement is evident.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
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