Coinfection of the secondary symbionts, Hamiltonella defensa and Arsenophonus sp. contribute to the performance of the major aphid pest, Aphis gossypii (Hemiptera: Aphididae)

In this study, we characterize the bacterial endosymbionts ofA. gossypii collected in Karaj, Iran and their role in the performance of the aphid. Our results indicated that besideBuchnera aphidicola,A. gossypii, also harbors bothHamiltonella defensa andArsenophonus sp. Quantitative PCR (qPCR) results revealed that the populations of the endosymbionts increased throughout nymphal development up to adult emergence; thereafter, populations ofBuchnera andArsenophonus were diminished while the density ofH. defensa constantly increased.Buchnera reduction caused prolonged development and no progeny production. Furthermore, secondary symbiont reduction led to reduction of the total life span and intrinsic rate of natural increase as well as appearance of the deformed dead offspring in comparison with the control insects. Reduction of the secondary symbionts did not affect parasitism rate of the aphid by the parasitic waspAphidius matricariae. Together these findings showed thatH. defensa andArsenophonus contributed to the fitness ofA. gossypii by enhancing its performance, but not through parasitoid resistance.
Source: Insect Science - Category: Biology Authors: Tags: ORIGINAL ARTICLE Source Type: research