Field Comparison of Annular and Straight Capillary Wick Irrigation with Drip Irrigation in an Arid Red Globe Vineyard

Capillary wick irrigation offers a passive means of gradual water delivery, but field evidence comparing wick configurations with conventional drip irrigation remains limited. This study compared annular capillary wick irrigation (AI), straight capillary wick irrigation (SI), drip irrigation (DI), and a non-irrigated rainfall-only control (NI) in a Red Globe grapevine field experiment in Ningxia, northwest China. Each irrigated experimental unit consisted of one reservoir supplying three grapevines and received four 90 L irrigation events, corresponding to a seasonal applied irrigation amount of 360 L per experimental unit. The local soil moisture at a monitored 10 cm depth, vegetative growth, berry development, yield, fruit quality traits, physiological indicators, and irrigation water productivity were evaluated. The capillary wick treatments generally showed a more persistent local soil moisture response than the more rapid post-irrigation response under DI. AI had the highest-recorded treatment mean yield (11.97 kg experimental unit−1), irrigation water productivity among the irrigated treatments (0.033 kg L−1), final 100-berry weight (864.49 g), and soluble solids content (18.77%). A 13-indicator AHP–Entropy Weight evaluation ranked AI first (0.8765), followed by SI (0.5129), DI (0.4860), and NI (0.3502); the same treatment order was retained in a sensitivity analysis using mean SPAD readings. Because the archived dataset did not permit consistent reconstruction of experimental unit identity for all response variables, the treatment differences are interpreted descriptively rather than as inferential statistical effects. These results provide preliminary field evidence that annular capillary wick irrigation warrants further engineering evaluation as a delivery configuration, while direct measurements of hydraulic discharge, spatial wetting patterns, and long-term operational reliability are required before its broader application.