Stock composition of northern neotropical honey bees: mitotype and morphotype diversity in Mexico (Hymenoptera: Apidae)

Abstract

-The stock of honey bees in the northern neotropics is likely a composite of European and African lineages, but the genetic makeup of most populations in this region has remained unstudied. We analyzed the genetic composition of honey bees across temperate and tropical regions of Mexico using mitochondrial and morphometric analyses. The results showed that honey bees from Mexico are descendent almost in similar proportion from matrilines of African and European origins. However, morphometrics indicate that most colonies are the result of extensive introgressive hybridization with Africanized bees. While large-scale displacement of European honey bees seems to have occurred in the tropical regions, higher frequencies of colonies with a mixed range of AfricanEuropean markers were identified in the temperate areas. Our results suggest that the outcome of the hybridization between Africanized and European honey bees in Mexico has been significantly associated with climate.Apis mellifera / Africanization / introgressive hybridization / mtDNA / morphometrics

Onset of foraging and lifespan of Africanized honey bees (Apis mellifera) infected with different levels of Nosema ceranae spores in Neotropical Mexico

“…The effects of N. ceranae on honey bees from tropical regions have been poorly documented, mostly limited to reports of the presence of this microsporidium in different countries (Guzmán-Novoa et al 2011;Teixeira et al 2013;Santos et al 2014). In tropical and subtropical Mexico, Africanized honeybee (AHB) colonies are predominant (Domínguez-Ayala et al 2016). In Brazil, laboratory studies have confirmed a reduced survival of Africanized honey bee workers infected with N. ceranae under controlled conditions (Gregorc et al 2016).…”

The Process and Outcome of the Africanization of Honey Bees in Mexico: Lessons and Future Directions

“…Presently, the process of Africanization of Mexico's honey bees seems to have stabilized to a large extent (Domínguez-Ayala et al, 2016). In general, the honey bees of Mexico show evidence that hybridization has occurred extensively and that climate drives introgression of African genes into local populations.…”

“…Recently, a comprehensive study including 500 colonies collected from the five beekeeping regions of Mexico yielded a better picture of the current genotypic composition of honey bees in the country (Domínguez-Ayala et al, 2016). About half of the colonies sampled (51.5%) had African mitotypes.…”

“…A corollary is that breeding programs in Mexico and elsewhere in the Neotropics, may benefit from using honey bees that are already present and better adapted to their respective tropical and temperate zones. These populations have been largely confronted to various environmental conditions and in the process are better adapted compared with foreign stock (Domínguez-Ayala et al, 2016). This is particularly relevant considering the low frequency of massive colony losses in Mexico and Latin America due to Colony Collapse Disorder and diseases, compared to what occurs in the United States and Europe (Vandame and Palacio, 2010).…”

Intranidal temperature and body size of Africanized honey bees under heatwaves (Hymenoptera: Apidae)

“…The tropical Yucatan Peninsula of Mexico is among the top beekeeping areas in the world (Echazarreta et al 1997). Indeed, the most productive beekeeping is practiced in the tropical and subtropical areas of Mexico where AHBs are predominant (Quezada-Euán 2007; Domínguez- Ayala et al 2016). Environmental temperatures in the Peninsula can reach up to 45°C during the dry season between April and June (Poot-Báez 2018).…”