Warren Kronstad, a wheat breeder from Oregon State University, gave an invited talk on breeding strategies in self-pollinated crop species to achieve and maintain adaptability. His presentation was a wake- up call for all breeders regarding the adaptive problems that can arise with breeding programs based on a narrow genetic base. Warren presented an overview of wheat breeding, and the current race to maintain or improve grain quality and quantity, while staying ahead of the many types of rust that can devastate crops. As hybrid wheat cultivars become near- homozygous lines after five generations of selfing, strategies for maintaining adaptability are important. In recent years, wheat yields have levelled out while worldwide wheat consumption has risen.
Diseases overcome genetic resistance in new cultivars in just a few years.
Wheat breeders are now employing a variety of strategies to develop broad adaptability including testing and selection over a wider range of environments, deployment of cultivar mixtures rather than planting isogenic crops, and developing hybrid cultivars. After hearing of the woes of wheat breeding, the focus turned to maintaining adaptability in tree breeding populations. Reinhart Stettler drew on his extensive research experience to discuss the role of adaptability in poplar culture. He addressed issues of phenotypic plasticity, developmental homeostasis and yield stability with respect to adaptability in poplar species. Populus trichocarpa was used as an example to discuss morphological, anatomical and physiological mechanisms of adaptability in poplars.