Population genetics of Anastrepha fraterculus (Diptera, Tephritidae) in different hosts: genetic differentiation and heterozygosity

An allozymic survey of 11 populations of Anastrepha fraterculus Wied. (Diptera, Tephritidae) in 8 different hosts from the same orchard revealed very small levels of genetic distance (D = 0.002 plus or minus 0.001) between hosts. The data thus provide no evidence for host-dependent genetic differentiation. Low values of heterozygosity were observed (H = 0.050 plus or minus 0.28) and 6 loci out of 11 were monomorphic. Biological attributes of the species, such as its polyphagic regime, multivoltine pattern of reproduction, and seasonal changes in population size, are discussed in an attempt to explain the low variability.