Water use efficiency of alfalfa varieties (Medicago sativa) with subsurface irrigation system

A study was carried out to evaluate the efficiency of irrigation water in the production of dry matter and crude protein in five varieties of alfalfa and two irrigation systems in Zacatecas. Planting date was on February 2012. Split plot design was used. Irrigation systems evaluated were subsurface drip (SSD) and basin flooding; and also the alfalfa varieties: Silverado, Jupiter, 58n57, Excellent and Giant. Statistical analysis performed was split plot using the SAS statistical package. The dry matter production (DMP) was not affected by the irrigation system (P>0.05), with an average for the total of five cuts of 15,561 and 14,121 kg ha(-1) for SSD and basin flooding systems; respectively. As for varieties only differences (P<0.05) were found in the third cut to DMP, standing out Giant and Jupiter with 4,638 and 4,263 kg ha; respectively. There was no interaction between irrigation* variety (P>0.05). Irrigation systems did not affect the percentage of crude protein and crude protein production of forage. The SSD system reduced by 44 % the volume of water applied compared to the basin flooding. Moreover in the same way increased the efficiency of irrigation water in the production of dry matter and crude protein forage by 49.2 and 50.9 % respectively.