Comparison Between the Prognostic and the Traditional Methodology of Crop Genetic Improvement.

Prognostic breeding is different from the traditional methodology of crop improvement. The foundation of traditional breeding is based on two choices that have not been critically investigated. One is the adoption of the densely grown field plot as unit of evaluation and selection, instead of the individual plant grown in the absence of competition. The second is the adoption of progeny lines available in the following generation, for measuring plant stability and heritability, instead of adopting sibling lines available in the current generation. The consequence of these two choices has been the limited annual genetic gain at the level of approximately 1% in all crops for more than one century. Recommended solution is the application of the principles of prognostic breeding, an integrated crop improvement methodology enabling selection of plants with high crop yield potential. These principles are embodied into an innovative equation with two parameters, measured accurately in honeycomb designs via moving replicates and moving grids. The first parameter measures the single plant yield potential devoid of the confounding effect of soil heterogeneity. The second parameter, by sampling effectively soil heterogeneity, measures accurately the stability and heritability of the sibling line to which each plant belongs. The product of the two parameters gives the crop yield prognostic equation which is used to rank and select plants according to their crop yield potential. As a consequence, the prognostic equation accomplishes four important objectives. The first objective is the effective selection of “champion” plants with high crop yield. The second objective is the application of very high selection pressures (1% to 0.5%) for achieving higher annual genetic gain. The third objective is investigating the possibility of automating the genetic improvement of crops. The fourth objective is the elucidation of the genetic basis of crop improvement.