This chapter reviews the key stages in corn plant development when water deficits can most impact on productivity. It reviews progress made in genotyping and phenotyping that enable selection for improved productivity in water-limited growing conditions. Technical approaches to experimental design and data analysis that can facilitate discovery, validation, and implementation of research outputs at a commercial level are also described.

Elhan Ersoz, University of Illinois at Urbana-Champaign and Umbrella Genetics, USA; and Robert J. Bensen, Umbrella Genetics, USA

• 1 Introduction
• 2 The importance of corn
• 3 Impacts of water deficits during the life cycle of the corn plant
• 4 Breeding objectives for improving performance under water deficits
• 5 Hypothesis-driven and genetic mapping studies to identify candidate genes
• 6 Transgenic approaches to improving tolerance to water deficits
• 7 Hybrid breeding for improved performance under water deficits
• 8 Genotyping assays and data: linking phenotype and genotype
• 9 Analytical methods to facilitate breeding: genome-wide association studies, genomic selection and beyond
• 10 Beyond association mapping and genomic selection: next-generation modeling approaches with machine learning
• 11 Conclusion
• 12 Acknowledgements
• 13 References