chemicals allowed farmers to provide the right environment to achieve maximum production with widely adapted crop varieties. However, in the developing world where resources are not sufficient to allow farmers to modify adverse environments, farmers and crop scientists have had to tailor technology to specific environments. The "Green Revolution" had a large and critical impact on food production in this part of the world, but it affected mostly those
farms blessed with the better environments. It has 'been only
recently that organized development efforts have been able to reach the majority of farmers -- those with few resources and living in relatively hostile environments -- by adapting technology to their environments. Now, in the developed world, with increasing concern for an agriculture that is environmentally and economically more sustainable, crop adaptation to environment, rather than adapting environment to the crop, is also becoming more important.
"The traditions of farming have usually been called for deciding on a crop variety and pushing and pulling on the environment until it grows that variety. But in the past few years, an increasing number of scientists have been
approaching the problem of growing crops at the extremes of climate and soil type from the other side of the problem. Rather than figuring out what has to be added
to the soil or which way to shift the planting date, they have been adapting the crops -- breeding them to naturally suit the circumstances instead of manipulating
their environment."1 (J.K. Kaplan, 1989).
Breeding for broad adaptability requires a different
interpretation and approach to the stability analysis procedure than breeding for specific adaptability. This paper discusses the
use of a modified approach to stability analysis (Hildebrand, 1984) as an important research tool that can provide the basis for an effective and efficient plant .breeding program for which adaptability to specific environments is desired as a critical factor in enhancing the sustainability of agriculture throughout the world. First, the philosophical history of stability analysis
is discussed. Then, the effect of this history on plant technology development is argued. Finally, the farming systems philosophy is
discussed and the use of stability analysis in this approach is presented.
pKZLosorIcAL ISTORY OF STABILITY ANALYSIS
Yates and Cochran (1938), apparently the first to conceptualize stability analysis, understood the potential 'to differentially recommend varieties based on their performance in different environments: "The fact that the experimental sites are a random sample of this nature does not preclude different
recommendations being made for different categories included in this random sample" (p.557). In fact, they argue that "1... the, deliberate inclusion of sites representing extreme conditions may
be of value" (p.558). However, the primary concern in their
seminal article was the statistical problem of how to evaluate mean
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