Investigating the adaptive genetic landscape of global crop species

Abstract

Improving environmental adaptation in crops is essential for sustaining food security in the face of global climate change. Recent advances in high-throughput genomic sequencing and phenotyping technologies have enabled researchers to identify and validate the genetic factors shaping adaptation. In this dissertation, I investigated the genetic basis of environmental adaptation in global cereal crops, focusing on the staple crop, maize (Zea mays L.), and the orphan crop, tef (Eragrostis tef Zucc.). In Chapter 2, I employed a landscape genomics approach to identify the genetic and environmental drivers of adaptation in a georeferenced collection of Ethiopian tef. In Chapter 3, I utilized both forward and reverse genetic approaches to evaluate the precision of phenotype-genotype mapping across multiple phenotyping methods for quantifying root system architecture in field-excavated maize. In Chapter 4, I applied a functional genetics approach to characterize a novel gene model in maize predicted to regulate root system development and nitrogen capture under field conditions. Collectively, this work provides valuable insights into the complex relationships between phenotype, genotype, and environment, contributing to our understanding of adaptation in two distinct and vital crop systems.