Is there a niche for physiology in future genetic improvement of maize yields?

SLAFER, G.A.; OTEGUI, M.E.

Physiological Bases for Maize Improvement.

Food Product Press

Lugar: New York; Año: 2000; p. 1 - 13

World population is (and will be for the decades to come) growing fast and demanding agriculture to produce more and more efficiently. As the arable area is not expected to increase significantly, more food and fiber can be produced only if yields keep increasing, at least at a similar pace to that of the last half of the 20th century. Maize is one the most important crops, and its yield has increased even faster than the world population during the last five decades or so. These increases were due to the synergetic effects of (i) using higher-yielding cultivars (initially replacing open pollinated cultivars by hybrids and then largely improving their yielding capacity together with the replacement of double-crossed by single-crossed hybrids), and (ii) improved management (including a large increase in the usage of fertilizers and herbicides). It appears now that the required future gains in yield would depend far more strongly upon genetic gains than those observed in the past. In the future, however, it seems that genetic gains in yield will be harder to obtain than in the past. In fact, we can find already incipient signals that current trends do not keep pace with increases in population. In this context, efforts to find alternatives to complement conventional breeding, which has always been an academically interesting task, seems empirically opportune. It will be undoubtedly helpful to increase our understanding of physiological processes that may help identifying realistic opportunities for future breeding. In this book we attempted to compile the current knowledge in this field to identify prospect characteristics that may be useful in realistic breeding programs, either to directly select for or to identify prospective traits that might be then selected with molecular tools, widening the usefulness of molecular biology to more quantitative characters.