The red oaks of California include only 4 species, but together they occupy a wide range of habitats in California. These include the iconic oak woodlands of the mediterranean ecosystem that characterizes the California Floristic Province. Many of these habitats are at greatest risk from human activities, including land conversion to urban development and agriculture. They are also habitats that will be seriously affected by climate change. The red oaks of California are keystone species in many ecosystems, providing forage, nurseries, shelter and other substrates for a very wide range of taxa from different organismal groups. Their protection is crucially important for overall biodiversity within the state. We have chosen Quercus wislizeni (interior live oak) for the reference genome because it has the widest range of the 4 species in California. It is closely related to the Quercus parvula complex that includes a variety (var. parvula) that is listed as Endangered. Indeed, the Quercus parvula group can be difficult to identify from Q. wislizeni and the two taxa are commonly misidentified. Q. wislizeni regularly hybridizes with Q. agrifolia (coast live oak) with which it frequently hybridizes. We will be re-sequencing range-wide collections of Q. wislizeni, the Q. parvula complex and Q. agrifolia. We anticipate that the close relationships between these taxa will mean that a single reference genome can be used for all species. Our study questions directed towards climate-related adaptation will include a landscape genomics study of environmental-related genomic structure, the role of hybridization in environmental adaptation and the phylogenetic relationships within the group.
Submitted by Richard Dodd, UCB