Effects of water-saving pruning on the growth and water consumption of jujube (Ziziphus jujuba Mill.) in a loess hilly region with deep soil desiccation

In order to study whether jujube trees can grow normally under rain-fed conditions in loess hilly areas, we planted jujube trees (Ziziphus jujuba Mill.) 4 years after felling a 23-year-old apple orchard. The growth process of the jujube trees and the variation in soil water content (SWC) were monitored for three consecutive years following planting in order to study the effects of the water-saving pruning (WSP) technique. Results showed the following. (1) The soil at a depth of 0–1,000 cm had been desiccated when the area was an apple orchard. (2) Under rain-fed conditions, the jujube trees with the WSP technique were always able to maintain normal growth while the jujube trees with conventional pruning method had a normal growth stage of only 4 years. The water use efficiency of the jujube trees with the WSP technique was much higher than that of the jujube trees with conventional pruning. We recommend WSP in jujube orchard management, because the jujube trees with WSP could maintain normal growth in the deep dried soils of the loess hilly region, as WSP can reduce the water consumption of the jujube trees and may have a positive effect on soil moisture restoration. HIGHLIGHTS We proposed water-saving pruning for the growth of jujube trees planted in dry soil.; Water-saving pruning can significantly improve water use efficiency of jujube trees planted in dry soil.; Water-saving pruning may have a positive impact on the restoration of soil water in dry soil.