Project

Genomics and Evolution of Lettuce Crop-Wild Relatives

Domesticated lettuce (Lactuca sativa of the plant family Asteraceae) looks and tastes quite different than its wild relatives which for example usually have spines and milky latex in their leaves. The domestication of lettuce also meant the species went through a genetic bottleneck and thus lacks diversity in pathogen and pest defense genes.

We want to understand the evolution of the genus Lactuca and to find new sources of resistance and genes for novel traits. Thus, we have undertaken fundamental phylogenetic studies of the genus, including species sampling of Lactuca species from Asia and Africa to get a more complete and robust evolutionary framework. We have also completed whole genome sequencing and assembly of two of the most important sources of novel resistance genes, namely L. saligna and L. virosa.

We also have also generated 500 single seed descent lines and resequencing data in collaboration with the Center for Genetic Resources (CGN) and Biosciences Group at WUR. In collaboration with KeyGene, we cloned an important gene for apomixis (specifically parthenogenesis) and demonstrated how the gene maybe useful in lettuce breeding. Finally, we are constructing a phylogenomic synteny framework for the entire Asteraceae family, with the goal of facilitating evolutionary and functional analysis for any lettuce gene to any of the nearly 40,000 other Asteraceae species.

Publications