Fresh and frozen dried fruit mites (Carpoglyphus lactis) supported the rearing of a predatory mite Phytoseius leaki (Acari: Phytoseiidae) with specialised niche requirements

The structural features of plant surfaces play a crucial role in the survival and development of phytoseiid mites, yet the specific requirements remain understudied. We investigated the effects of fibrous materials and leaf trichomes on the survival and life history traits of a predatory mite, Phytoseius leaki Schicha. Despite access to abundant food and moisture, no individuals survived to the deutonymph stage in artificial rearing cells lacking fibrous materials, suggesting that structural cues are essential for immature development. Protonymphs exhibited minimal feeding before mortality, indicating that the absence of a suitable niche may have induced stress-related effects. Comparisons between fabric substrates and the leaf discs of woolly nightshade (Solanum mauritianum Scop.) revealed accelerated development on leaf surfaces but reduced fecundity and lifespan, potentially due to toxic biochemical products. Laboratory trials demonstrated that both live and frozen Carpoglyphus lactis (L.) eggs supported the development and reproduction of P. leaki, although frozen eggs reduced interference from live mites and waste accumulation. These findings highlight the structural requirements of P. leaki, emphasising the importance of leaf trichomes in shaping its habitat distribution and potential role in managing pests associated with pubescent plants.