Resumen

SIFUENTES IBARRA, Ernesto et al. Irrigation scheduling in pecan (Carya illinoinensis), through an integrated model based on thermal time. Rev. Mex. Cienc. Agríc [online]. 2015, vol.6, n.8, pp.1893-1902. ISSN 2007-0934.

In recent years, Mexico has been placed among the main producers of walnuts in the world with more than 44 000 ha, established mainly in the irrigated areas of the north, where water availability is scarce. Most studies report a high demand for water from this excess of 1 100 mm annual crop, which increases competition for this resource, more acute in periods of drought. Irrigation scheduling in real time based on thermal time (degree day) has been widely used in grains and vegetables in the State of Sinaloa, Mexico, allowing water availability scenarios handle and use, with water savings of 1 600 m3 ha-1 in maize, without reducing yield. This study was adapted, through a parameterization of the previous base model for growing pecan, in an orchard of Laguna Region of Coahuila, Mexico, for which the model parameters were determined experimentally related to the crop coefficient (Kc), dynamic root depth (Pr) and abatement of soil moisture (f), all based on the thermal time accumulation. The validity of the model was determined by comparisons between measured and modeled variables of phenology, temporal variation of the moisture content in the soil profile and yield. The model estimated a requirement irrigation of 741 mm for the sprouting starting period to harvest (pre-sprouting irrigations were not considered) with a total degree days accumulation of 2 449.54. It also allowed to model the variation in the length of the phenological stages at different times of sprouting, which was higher than 20 calendar days for most of the stages, which affects crop management, it was also possible to generate irrigation schedules for different planting dates, soil and irrigation systems.

Palabras llave : irrigation systems; moisture content; nut; phenological stages.