Infraspecific variation of Sechium edule (Jacq.) Sw. in the state of Veracruz,Mexico

In this study a morphological and anatomical variation analysis was carried out with leaves and fruits of Sechium edule, collected in the central region of Veracruz, Mexico. The collected fruits were classified in eight groups according to their typical characteristics. The results showed that the phenotypical distinction of the studied infraspecific S. edule complex is related to morphological and anatomical changes in order to improve the adaptive specialization of the different chayote types with respect to the environment, and suggests that cultivated chayotes have followed different routes in the process of co-evolution with man, showing stable variation patterns in the so-called “green” and “yellow” groups. Considering the phenotypic variability existing in the analyzed characters, a certain prediction may be proposed about the direction the variation patterns may follow facing the transference of chayotes to environments of lower altitudes than mountain cloud forest.