Optimizing the consumptive irrigation water use in a young drip-irrigated almond orchard

F. Montoya, J.M. Sánchez, J. González-Piqueras, L.L. Simón, F. Valentín, R. López-Urrea
In arid and semiarid Mediterranean agro-ecosystems, where the surface area of almonds grown under irrigation is increasing each year, technicians and growers demand operative tools and practices which aid in using limited irrigation water resources more efficiently. A field experiment was carried out during two growing seasons in southeast Spain to assess the crop growth, the crop water requirements, and the productive response of young almond trees irrigated using both surface (DI) and subsurface (SDI) drip-irrigation systems. In this experiment we used the FAO56 methodology to determine the irrigation scheduling. Several crop growth samples, crop water status samples, and soil moisture measurements were collected during both cropping seasons. In addition, each treatment had two towers equipped with a set of thermal infrared broad-band radiometers to measure both soil and canopy temperatures which allowed us to estimate the crop evapotranspiration (ETc), tree transpiration (Tc), and soil evaporation (Es), using a simplified version of the Two Source Energy Balance (STSEB) approach. SDI resulted in water savings of around 12% in comparison with the SDI, and there were not significant differences on yield, tree growth and tree water status between the two irrigation systems. The midday stem water potential (Ψstem) was related with the measured soil water content, showing us that a depletion of up to 45-50% of the total available water would maintain good water status (Ψstem≥-1.0 MPa) in almond trees. These encouraging results suggest that SDI is a suitable alternative for reducing the non-productive water use resulting in water savings and maintaining the crop yield in almond orchards.
Montoya, F., Sánchez, J.M., González-Piqueras, J., Simón, L.L., Valentín, F. and López-Urrea, R. (2024). Optimizing the consumptive irrigation water use in a young drip-irrigated almond orchard. Acta Hortic. 1406, 137-144
DOI: 10.17660/ActaHortic.2024.1406.20
https://doi.org/10.17660/ActaHortic.2024.1406.20
almond growth, plant-water status, simplified two-source energy balance, crop evapotranspiration, nut production
English

Acta Horticulturae