Biochemical evidence of haplodiploidy in the whitefly Bemisia tabaci.

Polymorphic esterase and acetylcholinesterase alleles in the whitefly Bemisia tabaci were studied using electrophoretic and colorimetric assays. The segregation of these alleles between parental and F1 generations provided unequivocal evidence of haplodiploidy in this pest species. Unmated females, heterozygous at a polymorphic locus, produced a 1:1 ratio of haploid males expressing either of the maternal alleles. Although male offspring were produced by both virgin and mated females, the segregation of alleles showed they were always haploid (hemizygous) for the marker enzymes. Females only arose from fertilized eggs and invariably expressed paternal and maternal alleles.