Effects of alternate partial rootzone irrigation on roots activity,stem sap flow and fruit of apple

In order to save irrigation water and improve irrigation patterns, field experiment was conducted in the Taihang Mountain gneiss orchards to evaluate the effects of different irrigation patterns, i.e, 3/4, 1/2, 1/4 alternate partial root-zone irrigation, 1/2 fixed partial root-zone irrigation, conventional border irrigation and non-irrigation on roots activity, stem sap flow, fruit yield and quality of Changfu-2 apple. The results showed that the root activities of which under irrigation area of alternate partial root zone irrigation were higher than that of conventional border irrigation in all period, the average root activity of which under 3/4 alternative irrigation was the highest, and had no significant difference with that of 1/2 alternating irrigation and conventional border irrigation; stem sap flow flux gradually decreased with the reduction of irrigation volume, the minimum irrigation volume to maintain stem sap flow was 1/2; Fruit yield per plant of 1/2 alternating irrigation had reduced by 7.10% as compared to conventional border irrigation, but had no significant difference compared with 3/4 alternative irrigation, and sugar-acid ratio of 1/2 alternating irrigation was the highest. This research suggests that 1/2 alternating irrigation has the potential for use as a high-quality efficient irrigation pattern in gneiss mountain orchards.