Prevalence in Potato of ' Candidatus Arsenophonus Phytopathogenicus' and ' Candidatus Phytoplasma Solani' and Their Transmission via Adult Pentastiridius leporinus.

Simple Summary: The planthopper Pentastiridius leporinus is the main vector of two bacterial pathogens (Arsenophonus and stolbur phytoplasma) that cause a disease known as syndrome basses richesses (SBR) in sugar beet, reducing the yield and sugar content. In 2022, P. leporinus nymphs were also found to transmit Arsenophonus in potato fields, causing symptoms like wilting, yellow leaves, and rubbery tubers. We monitored both pathogens in Southwest Germany in 2022 and 2023, revealing that P. leporinus adults can transmit Arsenophonus and stolbur to potatoes. The broad prevalence of Arsenophonus was maintained, whereas the prevalence of stolbur increased in most regions in 2023. Neither of the pathogens influenced the germination rate of potato tubers, and no abnormal growth was observed after germination. Arsenophonus was not detected in germinated shoots, but stolbur was present, emphasizing the need for plant material testing to prevent outbreaks of disease. The planthopper Pentastiridius leporinus (Hempiptera: Cixiidae) is the main vector of two bacterial pathogens: the γ-proteobacterium 'Candidatus Arsenophonus phytopathogenicus' and the stolbur phytoplasma 'Candidatus Phytoplasma solani'. These pathogens cause the disease syndrome basses richesses (SBR) in sugar beet (Beta vulgaris), which reduces the yields and sugar content. In 2022, potato (Solanum tuberosum) fields were found to be colonized by P. leporinus, and the transmission of Arsenophonus was confirmed, resulting in symptoms like wilting, yellow leaves, and rubbery tubers. We monitored both pathogens in Southwest Germany in 2022 and 2023. This revealed their widespread presence in potato tubers, although there were differences in regional prevalence. The broad prevalence of Arsenophonus was maintained in 2023, whereas the prevalence of stolbur increased in most locations. We confirmed that P. leporinus adults can transmit both pathogens to potatoes, but neither pathogen reduced the germination rate of tubers, and no plants showed abnormal growth after germination. Arsenophonus was not detected in germinated shoots, but 5.4% contained stolbur, emphasizing the need for plant material testing to maintain phytosanitary conditions. [ABSTRACT FROM AUTHOR]