Estimación del rendimiento de cebada (Hordeum vulgare L.) maltera con el método FAO

when using models to predict crop yields, with frequency there are limitations due to the variables fed into those models. hence, the need to select the model with either the smallest number of variables or variables that can be estimated by some well known procedures that are also easy to fit. the methodology provided by the agro-ecological zones project, proposed by the food and agriculture organization (fao) constitutes a good alternative, not only due to its simplicity, but also for the eco-physiological principles that support the processes for biomass production by crops. the use of this method allows for validating, calibrateing and fitting the model, according to the needed variables, these must be calculated in the field, experimentally or by a sampling procedure that evaluates an area or a region to make sure that the method estimates crop yields in an acceptable form (highly accurate and low bias). for the studied case in the barley crop, the method does not allow for the detection of the local variation in yield potential, but at a regional scale the method produces a reasonable average yield, therefore we suggest the increase of the study to explore differences among regions and genotypes. the results indicate the need for an adjustment factor to fao's methodology, so that the estimated yield approaches reality for both, region and genotype.. a relationship between the fitting factor of crop yield and spikes density per hectare, is presented.