Application of a productivity index in two soils units and its relation with sorghum crop, Low Guajira, Zulia State, Venezuela

The study was carried at the Venezuelan low Guajira, Zulia state, Venezuela, located at 11º09'50"-11º09'57", north latitude and 72°02'07"- 72°04'17", west longitude. Some chemical and physical soil properties were evaluated in two cartographic units (A.gc.5.fn-so and A.er.4.fp) selected under the approach of climatic homogeneity and the application of a similar management for crop production. It determined the soil productivity index (IP) and the yield of sorghum ( Sorghum vulgare Pers.) were determined in both cartographic units, in order to evaluate their potentialities and limitations comparing yield obtained with the predicted yield using the general equation of regression that relates the crop yield with the IP. Statistical Analysis System (SAS) was used, in a totally randomized model. Highly significant differences were detected (P