Determinación de requerimientos hídricos en el cultivo de lechuga (lactuca sativa) var: Winterhaven en base al tanque de evaporación tipo y fórmulas empíricas (FAO) en Macají, cantón Riobamba, provincia de Chimborazo

Abstract

The present investigation proposes : to determine the wather requirements for the cultivation of lettuce (Lactuca sativa var . Winterhaven based on drainage lysimeters , type A evaporation tank and empirical formulas (FAO) in Macaji. The essay was carried out with a Desing of Complete Blocks at RAndom (DCBR) and was adapted to drip irrigation conditions . Three treatments and three repetitions of irrigation were included , according to the abatement of the available soil moisture (T1 Lysimeter at the time of drainage, T2 Evaporation Tank 25% and T3 FAO empirical formulas at 25%) . The results showed that the different irrigation sheets affected the yield of the lettuce. The highest yield obtained with Treatment 1 (Lysimeter) with an applied volume of 440.90 , thus obtaining a yield of 29.6 t/ha. The evaluated variables were : height of the plant , number of leaves, polar diameter , Equatorial diameter , ralative wáter content , chorophyll content , days to harvest, weight of cabbage , total yield , percentage of dry matter ,and correlation between wáter used and yield (wáter footprint). Four phenological stages were establishid for cultivation from transplant to harvest : Number of plants lit (initial phase) , Days elapsed since transplanting , to the rosette phase (development phase) , Days elapsed until the formation of the cabbage (intermediate phase ) , Days elapsed until the harvest (final phase) . The Kc was determined and adjusted for each of the phonological stages . The values of Kc with which better yields were obtained (T1) 0.62/0.99/ 1/0.8 , for the initial stage , development , average and final respectively , results of the replacement of irrigation wáter at the time of drainage .

Keywords: HYDROLOGY –DRAINAGE LYSIMETER – IRRIGATION SHEETS – EVAPOTRANSPIRATION OF REFERENCE – CROP COEFFICIENT