Effect of Drip and Micro-Sprinkler Irrigation Systems on the Yield of Chinese Garlic (Allium sativum L.) in the Peruvian Altiplano

Water scarcity in the Peruvian Altiplano demands irrigation strategies that optimise water use without compromising agricultural productivity. The objective of this study was to compare the effects of drip irrigation and micro-sprinkler irrigation on the agronomic development, water balance, and yield of Chinese garlic (Allium sativum L.) in the community of Challapujo, Ilave, Puno, during the 2021–2022 growing season. Six plots were evaluated under two localised irrigation treatments: T-1 (drip) and T-2 (micro-sprinkler). The irrigation scheduling was based on a daily water balance, accounting for evapotranspiration, precipitation, effective root depth, and soil moisture thresholds. The soil exhibited analogous hydro-physical characteristics across treatments, with a bulk density of 1.28 g cm−3, a field capacity of 20.31%, and a permanent wilting point of 10.33% for T-1 and values of 1.31 g cm−3, 19.99%, and 10.16%, respectively, for T-2. The C-factor was calculated based the actual volume applied and the effectively wetted area, estimated at 80% for drip irrigation and close to 100% for micro-sprinklers. During the 190-day growing period, 84 effective irrigation events and a cumulative precipitation of 424.30 mm were recorded. Treatment T-1 required 1099.98 min of irrigation and applied 223.87 mm, whereas T-2 required 1280.75 min and 346.76 mm; this represented an absolute saving of 122.89 mm and a 35.5% reduction in favour of drip irrigation. Nevertheless, no significant differences were observed regarding to plant height, pseudostem diameter, leaf length, pre-bulbing stage, number of leaves, or yield—with values of 14.70 t ha−1 for T-1 and 14.83 t ha−1 for T-2. In conclusion, both systems yielded equivalent agronomic results, but drip irrigation demonstrated superior water-use efficiency, making it a technically favourable alternative for high-Andean production systems with limited water availability.