Plant breeding for climate change: Opportunities for adaptation and mitigation
Plant breeding for climate change: Opportunities for adaptation and mitigation
Patrick F. Byrne, Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado USA 80523<EMAIL_ADDRESS>Learning Objectives
- Summarize the past, present, and future use of plant genetic resources in plant breeding.
- Provide examples of strategies and successes of employing plant genetic resources to help plants adapt to climate change.
- Explain the potential use of plant genetic resources in breeding for climate change mitigation.
outline
- Introduction
- Past, present, and future use of plant genetic resources in plant breeding
- From genebanks to farmers’ fields
- Breeding plants for adaptation to climate change
- Breeding plants for climate change mitigation
- Conclusions
- References
- Acknowledgments
1. Introduction
Genetic diversity is the foundation upon which plant breeding progress rests. Therefore, diverse genetic resources have always played a key role in the improvement of crops from wild progenitors to elite cultivars. Given the relatively narrow genetic base of most modern crops, access to a broad range of genebank resources is essential to help breeders adapt crops to the extreme conditions predicted under climate change, as well as to breed plants that can mitigate those conditions.
2. Past, Present, and Future Use of Plant genetic resources in Plant Breeding
To place this chapter in perspective, we begin with a condensed, subjective assessment of the use of plant genetic resources (PGR) by plant breeders through the past, present, and future eras of plant breeding.
Past
Crop improvement in the broad sense has a long history of altering the genetics of plant populations for the benefit of human society. Plant breeding has had numerous notable achievements from the domestication of wild plants, to selection by generations of farmers for local adaptation, to scientific breeding starting around 1900. Often this progress has been accompanied by a narrowing of genetic diversity. Modern breeders have used genebank resources occasionally, especially for disease resistance traits controlled by major genes, but not for quantitative traits like drought tolerance, with their more complex inheritance. The vulnerability of major crops due to limited genetic diversity was emphasized by the southern corn leaf blight epidemic in the U.S. in 1970-71 (Ullstrup, 1972), but relatively little progress has been made to broaden the genetic base of many crops. Further description of the history of plant breeding is contained in the eBook chapter, From Wild Species to Landraces and Cultivars.
Present
There is growing recognition of the value of PGR, especially to help crops adapt to the stresses brought about by climate change (FAO, 2015). However, identifying the most useful accessions remains a challenge, as does incorporating the beneficial variation into commercially viable cultivars. Initiatives have been completed or are underway to conduct co