Resumen

QUIROGA GARZA, Héctor Mario  y  FAZ CONTRERAS, Rodolfo. Increase in Water Use Efficiency by Alfalfa with Water-Limiting Irrigations during Summer. Terra Latinoam [online]. 2008, vol.26, n.2, pp.111-117. ISSN 2395-8030.

With the objective of evaluating the effect on alfalfa (Medicago sativa L.) production using water-limiting irrigation during the summer a study was established in the La Laguna research station of the 'Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias' (INIFAP). Eleven treatments were evaluated with no irrigation during summer (July-September) by one, two or three growths starting in the first and the second year. In general, alfalfa was not affected by this extreme water management. The best treatments with water-limiting irrigation during August and September were those in the second year and during July in the planting year. The treatments in which irrigation was suspended showed higher stem density than the control when irrigation was resumed; however, their dry forage yield in 28 and 29 harvests was 1 and 2% lower than the control (68.8 Mg ha^-1 in 32 harvests). A total irrigation of 583.16 cm was applied to the control, while the two previous treatments received 13 and 9% less water, increasing the dry matter production efficiency from 1.18 to 1.34 kg dry forage m^-3 water applied. Withholding irrigation during the summer did not affect alfalfa production nor stand longevity, but it did increase the global efficiency of dry matter production.

Palabras llave : Medicago sativa L.; forage; water layer.