A descriptive analysis was made including the possible plants capable of producing an allergic reaction with pollen grains. We worked with 106 species from 30 families and 79 genera; only 57 species contributed to the collection with prepared pollen grains. In the same manner, morphologic descriptions of the pollen grains were conducted. Clinical charts were reviewed, selecting those patients who reacted positively to some type of pollen (1101 patients) and to some kind of food. This was corroborated by the ingestion of vegetal origin foods. The gramineous, leguminous, rosaceae, and solanaceae were the most important group of vegetal-originating foods which caused a positive reaction due to their ingestion and a skin reaction in 37.52% of the patients.