Plant-Mediated Horizontal Transmission of Asaia Between White-Backed Planthoppers, Sogatella furcifera

is a bacterial symbiont of sugar-feeding insects that has been shown to be vertically transmitted by maternal transmission and paternal transmission mechanism, and to be horizontally transmitted via co-feeding artificial diet and venereal routes. Here, the first case of plant-mediated horizontal transmission of between white-backed planthoppers (WBPH), , was reported. In -infected WBPH, was detected mostly in salivary glands and to a less extent in stylets. The rice leaf sheaths fed by -infected WBPH for 12 h were all positive with , where persisted for at least 30 d but was localized in the feeding sites only. When confined to -infected leaf sheaths for 7 d at the sites pre-infested by the -infected WBPH, all -free WBPH became infected with and the acquired could be vertically transmitted to their offspring. Phylogenetic analysis confirmed an identical strain in the -infected donor WBPH, the -infected leaf sheaths, and the newly infected recipient WBPH. Our findings provide direct evidence for the first time that rice plant can mediate horizontal transmission of between WBPH, which may contribute to the spread of in the field WBPH populations.