Scheduling irrigation for jujube (Ziziphus jujuba Mill.)

Abstract

This study was performed to select suitable indicator for scheduling the irrigation of jujube (Ziziphus jujuba Mill.) 
grown in the Loess Plateau. The relationships between plant-based indicators and soil matrix potential as well as 
meteorological factors of jujube under deficit irrigation compared with well irrigation were determined. The results 
showed that maximum daily trunk shrinkage increased and maximum daily trunk diameter, gas conductance and 
midday leaf water potential decreased in response to higher and lower soil matrix potential, respectively. However, 
the maximum daily trunk shrinkage signal intensity to noise ratio was highest in response to higher and lower soil 
matrix potential. Besides, the maximum daily trunk shrinkage correlated well with reference evapotranspiration and 
vapor pressure deficit (r2= 0.702 and 0.605 respectively). When the soil water potential was greater than -25kPa or 
less than –40 kPa, maximum daily trunk shrinkage values showed increasing trend, suggesting that Jujube might be 
subject to water stress. Based on this, the suitable soil water potential values of pear-jujube in anthesis and setting 
periods were identified between -40 kPa and - 25 kPa and the values can conduct precise irrigation of jujube in the 
Loess Plateau.