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

Abstract

Aphids live in symbiosis with a variety of bacteria, including the obligate symbiont Buchnera aphidicola and diverse facultative symbionts. The symbiotic associations for one aphid species, especially for polyphagous species, often differ across populations. In the present study, by using high-throughput 16S rRNA sequencing, we surveyed in detail the microbiota in natural populations of the cotton aphid Aphis gossypii in China and assessed differences in bacterial diversity with respect to host plant and geography. The microbial community of A. gossypii was dominated by a few heritable symbionts. Arsenophonus was the most dominant secondary symbiont, and Spiroplasma was detected for the first time. Statistical tests and ordination analyses showed that host plants rather than geography seemed to have shaped the associated symbiont composition. Special symbiont communities inhabited the Cucurbitaceae-feeding populations, which supported the ecological specialization of A. gossypii on cucurbits from the viewpoint of symbiotic bacteria. Correlation analysis suggested antagonistic interactions between Buchnera and coexisting secondary symbionts and more complicated interactions between different secondary symbionts. Our findings lend further support to an important role of the host plant in structuring symbiont communities of polyphagous aphids and will improve our understanding of the interactions among phytophagous insects, symbionts, and environments.

Diversity of bacterial symbionts associated with Myzus persicae (Sulzer) (Hemiptera: Aphididae: Aphidinae) revealed by 16S rRNA Illumina sequencing

“…In the present study, the microbiota of M. persicae was dominated by relatively few bacteria, which were primarily heritable symbionts. As in most other aphid species [22][23][24][25]44], B. aphidicola was the predominant symbiont in M. persicae, being present in all samples and showing the highest average relative abundance. This is due to the fact that B. aphidicola is required for aphid development and reproduction [3]; it is strictly vertically transmitted and has undergone long-term parallel evolution with its aphid hosts [5].…”

“…In recent years, high-throughput amplicon sequencing has become an effective method for understanding insect microbial communities and their dynamics. Although high-throughput sequencing techniques have been used by many studies to investigate the bacterial communities of specific aphid groups [22,23] and community changes within some aphid species [24,25], the symbiont diversity of most aphid species remains unknown or poorly characterized.…”

Host Plants Influence the Symbiont Diversity of Eriosomatinae (Hemiptera: Aphididae)

“…Geographical distribution has been reported to influence symbiont communities of populations of A. gossypii, whereas host plants seem to have no impact [52,53,[55][56][57]. However, based on extensive sampling efforts of A. gossypii, the study revealed that host plants rather than geographical distribution structured the symbiont community [50]. Strong associations between host plants and symbiont composition have been largely documented in pea aphid A. pisum and A. craccivora [45][46][47][48][49], whereas the role of geographical distribution in structuring aphid microbial communities has not been detected in these species.…”

“…The distributions of microbial symbionts differ across aphid species or populations, which may be influenced by both internal and external factors. The strong correlations between symbiont communities and host plants were revealed in Acyrthosiphon pisum (Harris) [45][46][47], Aphis craccivora Koch [48,49], Aphis gossypii Glover [50] and Phylloxera notabilis Pergande [51]. Studies have also found that aphid geographical distribution plays an important role in shaping symbiont microbiotas [52][53][54][55][56][57].…”

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

“…The factors that may determine the presence of facultative symbionts in aphid populations remain poorly understood. A recent study indicates that the bacterial fl ora associated with A. gossypii is strongly affected by its host plants (Xu et al, 2019). However, other studies indicate that the composition of microbial communities hosted by aphids may largely depend on host genotype (Fakhour et al, 2018;McLean et al, 2019).…”