Management of Nitrogen in Orchard Ecosystems
- Constructing Tree Nutrient Budgets
- Modelling nitrogen movement in the root zone
- Organic Matter amendments, soil health, nutrient and water cycling
- Barriers to adoption of new technologies by growers
- Whole system analysis of nitrogen flux from surface to groundwater
- Almond Yield Prediction through remote sensing, machine learning and modeling
Salinity and Boron Toxicity in Perennial Crops
- Salinity tolerance of almond rootstocks
- Boron toxicity principles and remediation technologies
Biostimulants: Their Role in Modern Agriculture
- Field testing platform for biostimulants
- Impact of biostimulants on the plant microbiome
- Updating leaching strategies for B in diverse soil types
Advanced Harvest Systems for Almond
- Almond Windfall
- Econometric analysis of advanced harvest systems for almond
- Utilization of recycled almond hulls and organic matter amendments in orchard crops
Dormancy Mechanisms in Perennial Orchard Crops
- Pistachio dormancy and the development of a quick test for tree dormancy status
Foliar Fertilizers
- Principles of foliar fertilization
- Effect of formulation and timing on nutrient uptake rate
- XRF analysis of nutrient uptake and movement in crop species
Coffee Agroecosystems
- Impact of plant nutrient management on soil health and plant resilience in coffee
Additional Detail for Select Projects:
Title: Developing Nutrient Budget and Early Spring Nutrient Prediction Model for Nutrient Management in Citrus.
Contact: Douglas Amaral (amaral@ucdavis.edu)
Current approaches to nutrient management in citrus rely heavily on leaf sampling collected during late summer which is too late to respond to deficiencies or adjust fertilizer regimes. The utility of leaf sampling can be improved if samples are collected early in the season so that farmers have enough time to respond to current tree nutrient status.
The objectives of the project are:
- Develop nutrient demand curves to guide the quantity and time of fertilizer application in mandarin and orange based on crop phenology.
- Develop an Early Season leaf sampling and nutrient prediction model for mandarin and orange.
- Develop and extend nutrient Best Management Practices (BMP) for citrus species.
Title: Effects of plant stimulants on nutrient concentration and mobility in plants. Studies utilizing micro X-ray fluorescence and plant genomics.
Contact: Douglas Amaral (amaral@ucdavis.edu)
Approaches involving the use of plant stimulants into foliar fertilizers with the rationalization that these additives will enhance the uptake, or subsequent mobility of the applied nutrient in food crops are still very poorly known. While very clear benefits from the addition of biostimulants have been observed, there were several circumstances in which no benefit were found.
The objectives of the project are:
- Utilize the X-ray fluorescence (µ-XRF) technique to obtain high spatial quantification (cellular and subcellular) of elemental distribution and transport following the application of various nutrient formulations and/or plant stimulants.
- Obtain a mechanistic understanding of the mode of action of plant stimuants through characterization of the phyllosphere microbiology, particularly changes in benefical microbial communities in a variety of species and to determine the best application method to attain these benefits.
Title: Improving nitrate and salinity management strategies for almond grown under micro-irrigation
Contact: Daniela Reineke (dreineke@ucdavis.edu)
The goal of this project is to investigate how irrigation management affects the spatial distribution of salt, nutrients and water in the root zone of almond trees and how the trees integrate the non-uniform moisture and salinity conditions resulting from drip irrigation. This will be done by combining measurements from a lysimeter experiment with a numerical modelling approach.
As part of this project, a web app was developed. This app shows the simulated spatial distribution of water and nitrate in the rootzone under drip or microsprinkler irrigation for various different timings of irrigation and fertigation and for different soil types. The simulations were carried out using the numerical modelling software HYDRUS.
Title: Advanced Field Screening Protocol for Biostimulants
Contact: Meerae Park (meepark@ucdavis.edu)
The Biostimulant Field Screening project will investigate the application of proximal sensing tools in the evaluation of biostimulant efficacy. The aim of this project is to identify biostimulants that merit further physiological research and optimize sensing technologies for precision agriculture. This project is an interdisciplinary collaboration between research teams from remote sensing and agricultural engineering.
Title: Evaluating HFLC Nitrogen Management Strategies to Minimize Reactive Nitrogen Mobilization from California Almond Orchards; Boron Remediation in Almond; Demonstration of a combined new leaf sampling technique for nitrogen analysis and nitrogen applications approach in almonds
Contact: Christine “Teena” Stockert (cmstockert@ucdavis.edu)