Morphometric and molecular analysis (mtDNA) of honeybees (Apis mellifera L.) in the state of Tabasco, Mexico

Abstract

Beekeeping in Mexico is based on subspecies of European (Apis mellifera L) and Africanized bees. Due to the difficulty in the morphological differentiation of the European (E) and Africanized (A) populations of A. mellifera, the objective of this work was to perform a comparative analysis between the FABIS morphometric technique, against the diagnosis using the restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA). Samples of bees from 135 commercial colonies (CC), 15 breeding colonies (BRC) and 3 wild colonies (WC), located in different municipalities of the state of Tabasco (N= 153), were used. Both diagnostic methods identified BRCs as European and WCs as Africanized, but in CCs, the FABIS method could not define 9 colonies, considering them as suspicious (S) and another 50 did not coincide with the result of the molecular method, so, in total, both methods coincided in 94 identifications (61.44 %). The Bayesian grouping based on the analysis of the twelve morphometric variables showed that the categories A-CC and E-CC form a group close to the category E-BRC; while the category A-WC presented the greatest distance, forming an isolated group. Therefore, CC bees have morphometric characteristics tending to E-BRC bees. This work is also intended to be a contribution to the lack of records on Africanization in the state of Tabasco. It is recommended to use the molecular method to discriminate between E/A bees, as it is not affected by environmental factors.