Morfología comparativa de granos de polen de Citrus aurantifolia (Christm.) Single 1913, Citrus limon (L.) Osbeck 1765, Citrus latifolia (Yu. Tanaka) Yu. Tanaka 1951 y Citrus medica (L.) 1853

The present research was carried out with the objective of determining the comparative differential morphological characteristics between the pollen grains of Citrus aurantifolia (Christm.) Single 1913, Citrus limon (L.) Osbeck 1765, Citrus latifolia (Yu. Tanaka) Yu. Tanaka 1951 and Citrus medica (L.) 1853, from Cajamarca and La Libertad, Perú. Samples of stems and branches with flowers were taken for taxonomic identification in the “Truxillense” herbarium of the Universidad Nacional de Trujillo(UNT), and palynological studies in the Genetics and Molecular Biology laboratory of the UNT, Trujillo, La Libertad, Perú. Dehiscent anthers of each species under study were isolated on a slide sheet, the pollen grains were stained with 0.5% safranin and were observed and photographed under an Olympus BX40 optical microscope at a magnification of 100X, recording the ornamentation characteristics and values. to establish shape, number, diameter of pores and thickness of the exine. The pollen grains in the studied species show reticulated exines, being predominantly prolatespheroidal, tetracolporate; with variable values of P/E, exine thickness and pore diameter between species and even within the same species, thus affirming theexistence of great interspecific and intraspecific genetic variability in the Citrus genus.