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

Abstract

Bacterial endosymbionts play important roles in ecological traits of aphids. In this study, we characterize the bacterial endosymbionts of A. gossypii collected in Karaj, Iran and their role in the performance of the aphid. Our results indicated that beside Buchnera aphidicola, A. gossypii, also harbors both Hamiltonella defensa and Arsenophonus sp. Quantitative PCR (qPCR) results revealed that the populations of the endosymbionts increased throughout nymphal development up to adult emergence; thereafter, populations of Buchnera and Arsenophonus were diminished while the density of H. 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 wasp Aphidius matricariae. Together these findings showed that H. defensa and Arsenophonus contributed to the fitness of A. gossypii by enhancing its performance, but not through parasitoid resistance.

The Bacterial Flora Associated with the Polyphagous Aphid Aphis gossypii Glover (Hemiptera: Aphididae) Is Strongly Affected by Host Plants

“…Spiroplasma had extremely low relative abundance (< 0.005%) in two aphid samples, which may explain why it was not found before. The defensive symbiont Hamiltonella defensa was reported to infect all A. gossypii samples examined by Zhao et al [74], Ayoubi et al [77], and Zhang et al [76]. However, in our study, it was just carried by six samples at very low abundance (< 0.005%).…”

“…Our data showed that Arsenophonus was the predominant facultative symbiont, with the highest infection prevalence and abundance. It has been reported in previous studies of A. gossypii [66,[73][74][75][76][77]. Jousselin et al [98] surveyed the distribution of Arsenophonus in aphids and revealed its high prevalence in the genus Aphis.…”

“…A. gossypii is currently controlled primarily by insecticides, which have been reported to influence the bacterial communities associated with aphids [75,76]. In addition, by utilizing quantitative PCR, Ayoubi et al [77] uncovered development-associated dynamics in the abundance of symbionts within A. gossypii.…”

Facultative symbionts associated with aphid populations in citrus orchards in northern Tunisia

“…However, in A. gossypii, the presence of at least one facultative symbiont is almost systematic. H. defensa was recorded in A. spiraecola but not in A. gossypii even though previous studies have reported the presence of H. defensa in this aphid (Zhao et al, 2016;Ayoubi et al, 2020). We recorded similar percentage infections of A. gossypii and A. spiraecola with S. symbiotica and R. insecticola, but the percentage infection of these aphids with Arsenophonus differed.…”

“…Bacteriophages required for protective symbiosis are recorded in various strains of this symbiont (Duron, 2014), but no defensive properties are reported for Aphis glycines infected with Arsenophonus (Wulff et al, 2013). Due to the high prevalence of Arsenophonus in populations of A. gossypii it is suggested that this facultative symbiont may be involved in host nutrition by mediating host plant range (Wagner et al, 2015;Zhao et al, 2016;Tian et al, 2019;Ayoubi et al, 2020).…”