Development of a virtual laboratory for growing salt-tolerant almond

Almond orchards in Central California, providing more than 80% of the global supply of this crop, are facing threats due to drought, groundwater salinization, and salt accumulation in the root zone. Traditional breeding of such trees is complicated by long juvenility periods and complex interactions between rootstock and scion. In this regard, the AlmondLab project was introduced, including a research protocol and a virtual laboratory for evaluating genetic constructs that enhance salt tolerance in almonds (Prunus dulcis).

Six candidates (C1–C6) have been developed for testing, utilizing adaptation mechanisms from marine algae, halophytes, and extremophiles. They target sodium extrusion via SOS1-type antiporters, sodium exclusion via HKT1 transporters, sodium compartmentalization in vacuoles, osmotic adaptation through mannitol accumulation, detoxification of reactive oxygen species using ascorbate peroxidases, and the strengthening of Casparian strips in the endoderm to prevent apoplastic breakthrough.

The experiment is conducted in a closed greenhouse system using precision lysimeters, reverse osmosis for water desalination, and nutrient remineralization. This prevents the discharge of saline runoff into the soil. The study covers 720 plants divided into 16 systems, using a Bayesian hierarchical assessment system. The primary criterion for efficiency is the canopy area over a 90-day period.

The project is supplemented by a computational platform with a command set for auditing and verifying all pipeline stages, as well as digital models for analyzing production costs under constraints on groundwater pumping and water price fluctuations from 50 to 2000 dollars per acre-foot.