Comparisons of Life-History Characteristics of a Genetic Sexing Strain with Laboratory Strains of Anopheles arabiensis (Diptera: Culicidae) from Northern Sudan

A genetic sex separation strain (GSS) has been created for Anopheles arabiensis (Patton) (Diptera: Culicidae), one of the major African malaria vectors, for use in controlling wild populations of this species via the sterile insect technique (SIT). This GSS strain, “ANO IPCL1,” allows sex separation by a translocation linking a dieldrin resistance allele and the Y chromosome. Differences between ANO IPCL1 relative to wild strains might reflect its field performance and therefore are of concern. Of more immediate interest is how differences might affect production during mass rearing. Life-history parameters were measured for the ANO IPCL1 strain and the two wild strains from which it originated. Although developmental rate differences were found among them, none were large. However, a major observed variation was the very low intrinsic fertility of ANO IPCL1 because of the translocation itself. This resulted in a much lower rate of increase: ANO IPCL1 was able to double its population size, in 7.8 ± 0.4 d, whereas Dongola and Sennar strains could do so in 4.9 ± 0.5 and 5.6 ± 0.4 d. The presence of the Y-autosome translocation mainly affected the natural fertility of the males, and this will require amplification steps during mass rearing.