ss the subjective visual human evaluation, even during the earliest segregating generations. Further, the equations are very appropriate for accurately phenotyping whole plants under real field conditions, bridging the gap between molecular-genomic and phenotypic data.
Overall, three essential, yet unappreciated reasons for the observed gaps between actual and potential crop yield, concern reduced stability of performance that should have been incorporated during the early segregating stages of cultivar creation through appropriate breeding methodology, any prevalence of big genetic or acquired differences in the crop stand that increases the CV of individual plant yield, and failure to practice nonstop selection after the release of cultivar to avoid degeneration and incorporate useful adaptive (genetic or epigenetic) de novo variation.
The author gratefully acknowledges stimulating discussions with Apostolos C. Fasoulas, Aristotelian University, Greece, which contributed to the final form of the manuscript.
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