Pistachio

 

Publications resulting from this research

Jacygrad E, et al. 2020. Phenotypic segregation of seedling UCB-1 hybrid pistachio rootstock. Trees, 34: 531-541.

Jacygrad E, et al. 2022. Comparison between field measured and UAV-derived pistachio tree crown characteristics throughout a growing season. Drones. 

Palmer W, et al. 2023. Genome assembly and association tests identify interacting loci associated with vigor, precocity, and sex in interspecific pistachio rootstocks. G3.

Kafkas S, et al. 2022. The pistachio genomes provide insights into nut tree domestication and ZW sex chromosome evolution. Plant Communications, XPLC 100497.

 

Pistachio Project

Pistachio is an increasingly important crop in California that is also fascinating genetically.  It is dioecious, has a small genome, and the predominant UCB-1 rootstocks are F1 seedlings from an interspecific cross between two clonally-propagated, heterozygous parents. The millions of rootstocks growing in commercial orchards in a variety of environments are possibly the largest set of full sibs on the planet. In collaboration with other labs at UC Davis and funded by the California Pistachio Research Board, we have identified loci associated with vigor, precocity, and sex. We have sequenced and assembled the parents of UCB-1 and identified a major QTL determining vigor as reflected by tree size.  One of our goals is to deploy molecular markers for vigor to allow nurseries to rogue out seedlings prior to planting in orchards that would later result in stunted trees. 

We are currently dissecting the genic basis for vigor and sex determination as well as developing methods for transformation and gene editing for pistachio. We aim to generate rapid-cycling rootstocks for accelerated breeding of non-GMO pistachio nuts.  We are investigating the structure of the sex chromosomes as a pre-requisite for our long-term goal of generating self-fertile, hermaphrodite pistachio trees.

Collaborating Labs