A field trial experiment has been started in the framework of INNOMED in the experimental fields of the Aula Dei experimental station (EEAD-CSIC) in Zaragoza, Spain. The purpose of this experiment is to improve our understanding of the effects of deficit irrigation on fruit production and quality parameters. The experiment has been set up in a pre-existing peach tree orchard with trees of the Extreme July variety.

Full irrigation up to 100% of the theoretical requirements will be applied for all the trees, except during the seed hardening period (approximately during the month of June), when four different treatments will be applied:

  1. 100% of irrigation requirements (ET0), established as the control treatment
  2. 50% of ET0
  3. 25% of ET0
  4. 10% of ET0

A fully randomised design with two trees and three replicates per treatment has been set up, and controlled dip irrigation will be used to apply the different irrigation levels.

Continuous-time soil humidity sensors from Decagon have been installed (one per treatment), at 10, 20 and 30 cm from the soil surface, and a recording frequency of 15 minutes. In addition, 12 soil sensor from Diviner have been installed up to a depth of 60 cm, and readings will be made manually at pre-defined times. The leaf water potential will be also recorded during the experiment, in order to relate the differences in soil moisture to the water stress in the trees.

Differences in yield, fruit size and weight, and fruit quality properties will be determined after harvest, and will be analysed in relation to the different irrigation intensities.