AUTHOR=Li Fei , Hua Hongxia , Ali Asad , Hou Maolin 

TITLE=Characterization of a Bacterial Symbiont Asaia sp. in the White-Backed Planthopper, Sogatella furcifera, and Its Effects on Host Fitness

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.02179

DOI=10.3389/fmicb.2019.02179

ISSN=1664-302X

ABSTRACT=<p>The white-backed planthopper (WBPH), <italic>Sogatella furcifera</italic> Horváth (Hemiptera: Delphacidae), is an economically significant rice insect pest that harbors a primary fungal yeast-like symbiont (YLS), and some secondary bacterial symbionts like <italic>Wolbachia</italic> and <italic>Cardinium</italic>. In the present study, an additional bacterial symbiont in WBPH was characterized. Phylogenetic analysis employing the 16S rRNA gene showed a bacterium closely related to <italic>Asaia</italic> of <italic>Nilaparvata lugens</italic> and <italic>Nysius expressus</italic>, and <italic>Asaia krungthepensis</italic>. TEM observation of the bacterium showed the typical morphology of <italic>Asaia</italic> sp. with signature filamentous structures in the nucleoid region. These results indicate that the bacterium belongs to <italic>Asaia</italic>. The <italic>Asaia</italic> bacterium was detected in all the tested individual adults and tissues of the laboratory WBPH population but showed varying infection rates (ca 45%) in the field collected WBPH populations. Quantitative PCR analysis revealed that <italic>Asaia</italic> sp. were significantly more abundant in WBPH females than males, and mainly distributed in the guts, fatty bodies, and salivary glands. <italic>Asaia</italic>-infected WBPH were of shorter nymphal duration and heavier adult weight than <italic>Asaia</italic>-free WBPH, while <italic>Asaia</italic>-free WBPH comparatively fed more, indicating that <italic>Asaia</italic> plays a role in improving WBPH fitness through involvement in host’s nutrient supply.</p>