Host-Associated Occurrence of Wolbachia in Natural Populations of the Pyriform Scale Protopulvinaria pyriformis (Cockerell, 1894) in Moroccan Orchards.

Scale insects are a highly diverse group of phloem-feeding pest insects that cause economic losses in a wide range of cultivated crops worldwide. Among these pests, Protopulvinaria pyriformis (Cockerell, 1894), recently reported in Morocco, represents an emerging threat to citrus (Citrus spp.) and avocado (Persea americana) production, two strategically important crops in the country. Like other hemipterans, P. pyriformis maintains close associations with prokaryotic endosymbionts, particularly Wolbachia, a facultative intracellular bacterium capable of influencing host reproduction, population dynamics, and interactions with host plants. Between June 2023 and March 2025, a survey was conducted in two adjacent avocado and citrus orchards in Kénitra, northwestern Morocco, to detect the presence of Wolbachia in natural populations of scale insects and assess its potential role in their population dynamics. A total of 180 individuals were collected (150 from Citrus sinensis and 30 from P. americana var. Hass) and subjected to molecular analyses. Detection of Wolbachia was performed by PCR targeting the coxA gene. Phylogenetic analyses revealed that the Moroccan isolate belongs to the A supergroup of Wolbachia. Only P. pyriformis collected from citrus tested positive for Wolbachia, with 90% prevalence, whereas specimens from avocado, despite high infestations, were negative. Within the citrus-avocado system examined, infection was observed only in populations associated with citrus, suggesting a host-associated pattern in this specific context. This study provides the first global evidence of Wolbachia infection in P. pyriformis in Moroccan orchards and provides a foundation for future research aimed at exploring the ecological significance of this association.