Plant Breeding and Whole-System Crop Physiology: Improving Adaptation, Maturity and Yield

Improvements in adaptation and maturity leading to greater yield are the most important criteria for the acceptance of a new crop cultivar, since yield improvement is one goal of virtually every crop breeding programme. Many such programmes have tended to concentrate on identifying the genetic traits responsible for higher yield and selecting each of them in the later stages of the breeding cycle. However, selection for yield per se is still the most effective method, since it is a combination of traits, operating within the limits of the system, which finally determines yield. This work presents a whole-system or holistic model for the improvement of adaptation, maturity and yield. Central to its thesis is recognition that competition between several components of the plant system, within a constant capacity, i.e. within the limitations of the system, determines yield and other cultivar characteristics. It goes on to describe how this can improve our understanding of plant systems. This understanding can then enhance the success of breeding trials by enabling a compromise to be reached between the different yield components which maximises performance under prevailing field conditions. Based principally on 25 years of research by the authors, the ideas presented in this book should be useful reading for crop physiologists and plant breeders.