Current Projects

  • Sequencing the gene space of gerbera daisies (NSF Plant Genome Program / ARI Campus; Co- PI Youngsook You)
  • Development of slow-bolting lettuce (ARI System; Co-PI Ryan Hayes)
  • Sustainability of lettuce production through breeding approaches to increase water and nitrogen use efficiency. (California Department of Food and Agriculture, Specialty Crop Block Grant Program)
  • Development of lettuce cultivars with increased water and nitrogen uptake (CDFA, SCBGP)
  • Identification of physiological and genetic factors associated with higher nitrogen use efficiency in lettuce grown under limiting nitrogen. (California Leafy Green Research Board / ARI Campus)
  • Sustaining the supply of high quality lettuce in changing technological and climatic environments (NIFA, SCRI; PI-Richard Michelmore)
  • Development of Lettuce Cultivars with Increased Water and Nitrogen Uptake
    Project description: Lettuce has a shallow root system that limits the amount of water and nitrogen uptake. Water is an increasingly critical and unpredictable resource and nitrogen fertilizers are known contributors to groundwater contamination and greenhouse gases. Developing cultivars with improved nitrogen and water uptake will reduce resource consumption, minimize environmental impact and enhance sustainability of lettuce production. To accomplish this goal, lettuce cultivars and accessions will be screened to: 1) Identify lines with the greatest root biomass, length and growth rates; 2) Identify lines with the greatest nitrogen uptake; and 3) Develop new F2 populations to determine the genetics of root biomass, water and nitrogen uptake. Superior genotypes identified in screens will be crossed with commercial cultivars that are typically shallow-rooted and have low nitrogen use efficiency. Determining the genetics of root growth and nitrogen uptake will facilitate successful breeding with this germplasm.
    Funding Agency:   California Department of Food and Agriculture, Specialty Crop Block Grant Program
  • Development of Lettuce Cultivars With Improved Water and Nitrogen Use Efficiency and Environmental Impact Assessment
    Project description: Lettuce size and quality are attained during production when water and nitrogen are not limiting. Water is an increasingly unpredictable resource and climate models predict less water for California. Greenhouse gases (GHG) drive global warming, and atmospheric nitrous oxide, a long-lived and potent GHG, increasing dramatically since 1940; nitrogen-based fertilizers are, by far, the major anthropogenic source. Since lettuce cultivars were developed under non-limiting water and nitrogen, developing cultivars with improved nitrogen and water use efficiency will lower the environmental impact of growing the crop and help ensure sustainability in California. This project seeks to, 1) advance the genetic lines created with previous CDFA funding, 2) develop commercially-viable molecular markers linked to high leaf nitrogen, 3) implement selection based on photosynthetic rate per unit of leaf nitrogen, and 4) assess GHG emission of lettuce grown under limited nitrogen.
    Funding Agency:   California Department of Food and Agriculture, Specialty Crop Block Grant Program