Influences of two coexisting endosymbionts, CI‐inducing Wolbachia and male‐killing Spiroplasma, on the performance of their host Laodelphax striatellus (Hemiptera: Delphacidae)

Abstract

The small brown planthopper Laodelphax striatellus (Hemiptera: Delphacidae) is reported to have the endosymbiont Wolbachia , which shows a strong cytoplasmic incompatibility (CI) between infected males and uninfected females. In the 2000s, female‐biased L. striatellus populations were found in Taiwan, and this sex ratio distortion was the result of male‐killing induced by the infection of another endosymbiont, Spiroplasma . Spiroplasma infection is considered to negatively affect both L. striatellus and Wolbachia because the male‐killing halves the offspring of L. striatellus and hinders the spread of Wolbachia infection via CI. Spiroplasma could have traits that increase the fitness of infected L. striatellus and/or coexisting organisms because the coinfection rates of Wolbachia and Spiroplasma were rather high in some areas. In this study, we investigated the influences of the infection of these two endosymbionts on the development, reproduction, and insecticide resistance of L. striatellus in the laboratory. Our results show that the single‐infection state of Spiroplasma had a negative influence on the fertility of L. striatellus , while the double‐infection state had no significant influence. At late nymphal and adult stages, the abundance of Spiroplasma was lower in the double‐infection state than in the single‐infection state. In the double‐infection state, the reduction of Spiroplasma density may be caused by competition between the two endosymbionts, and the negative influence of Spiroplasma on the fertility of host may be relieved. The resistance of L. striatellus to four insecticides was compared among different infection states of endosymbionts, but Spiroplasma infection did not contribute to increase insecticide resistance. Because positive influences of Spiroplasma infection were not found in terms of the development, reproduction, and insecticide resistance of L. striatellus , other factors improving the fitness of Spiroplasma ‐infected L. striatellus may be related to the high frequency of double infection in some L. striatellus populations.

Endosymbionts Reduce Microbiome Diversity and Modify Host Metabolism and Fecundity in the Planthopper Sogatella furcifera

“…However, this reduction effect does not always occur, such as in Anopheles coluzzii ( 37 ). In pests infected with two endosymbionts, one of them usually has a dominant effect on the bacterial microbiota ( 38 – 40 ). For example, in drosophilid flies, which were infected with both Wolbachia and Spiroplasma , Wolbachia had a much greater impact on microbes ( 38 ).…”

Benefits and costs of hosting facultative symbionts in plant‐sucking insects: A meta‐analysis

“…We searched for relevant literature using keyword searches in Web of Science finding articles published until the end of 2019 (details for each group below). Literature and data pertaining to other herbivorous sucking insects was searched for, but with few articles relevant to our meta‐analyses; data for three Auchenorrhyncha species hosting symbionts was extracted but this taxa does not belong to any of the three identified groups and was insufficient to analyse independently (Li et al, 2019; Shentu et al, 2019; Yoshida et al, 2019).…”

Effects of feeding on different parts of Ailanthus altissima on the intestinal microbiota of Eucryptorrhynchus scrobiculatus and Eucryptorrhynchus brandti (Coleoptera: Curculionidae)

“…For this result, we propose such a conjecture, Spiroplasma and Wolbachia in this study may have a competitive relationship. Cause male-killing Spiroplasma infection obstructs the spread of CI-inducing Wolbachia infection ( Yoshida et al, 2019 ). The ripeness of the feeding material is positively related to the relative abundance of Spiroplasma in E. brandti and Wolbachia in E. scrobiculatus .…”

“…The ripeness of the feeding material is positively related to the relative abundance of Spiroplasma in E. brandti and Wolbachia in E. scrobiculatus . A trunk diet might result in reproductive isolation between E. brandti and E. scrobiculatus , as the relative abundance of Wolbachia and gene flow toward the MK-infected island is increased when the relative abundance of Spiroplasma is high ( Engelstadter et al, 2008 ; Yoshida et al, 2019 ). However, some previous studies have shown that the abundance of Wolbachia in the gut is higher in laboratory environments, but the reason for this pattern remains unclear ( Liu et al, 2021 ).…”