Genetic diversity of wild papaya

In order to determine whether genetic architecture stems from pre-Pleistocene events or refugia, Chávez-Pesqueira and Núñez-Farfán assess genetic diversity and population dynamics of 19 populations of wild papaya (Carica papaya) from northern Mesoamerica.

The six genetic clusters (in blue) inferred from GENELAND using DNA microsatellite loci of natural populations of Carica papaya in Northern Mesoamerica. Solid black lines represent the location of the most probable barriers obtained with BARRIER for DNA microsatellite loci, and dotted black lines for the psbA-trnH chloroplast region.

Phylogenetic analysis using cpDNA markers indicates a lack of a phylogeographic structure, and nuclear markers reveal a recent population structure. This suggests that the evolution of C. papaya together with seed dispersal by animals could have contributed to long-distance colonization of lowland rainforests. Anthropogenic habitat disturbance poses a threat to the maintenance and longevity of wild papaya’s genetic diversity and population structure.