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• First report of a broader approach for developing an EPF based tick control agent. • Ca-alginate beads function as microfermenter for Metarhizium spp. blastospores. • Encapsulated blastospores maintained virulence against I. ricinus nymphs. • Most promising Metarhizium spp. isolate for control of I. ricinus was identified. As vectors of pathogens, ticks pose a considerable problem in most parts of the world. Most tick bites in Germany are caused by Ixodes ricinus for which there is no specific scientifically proven control agent available. Although biological control options like entomopathogenic fungi are known, there is a lack of studies on formulation and applicability. This study presents a broad biotechnological approach for the development of an entomopathogenic fungus-based tick control agent, considering virulence and cultivation as well as formulation of fungal isolates. First, five Metarhizium spp. isolates were pre-screened for their virulence against I. ricinus nymphs. Afterwards, three virulent isolates were cultivated on solid medium as well as in submerged cultures. The highest concentrations were obtained with the isolate M. brunneum Ca8II both on solid medium (4.65·107 conidia·cm−2) and in submerged cultures (2.93·107 blastospores·mL−1), whereas M. pemphigi X1c obtained the highest total dry weight (86 g·L−1). Then, blastospores of the isolates were encapsulated in calcium alginate, supporting growth of fungal biomass and ensuring formation of aerial conidia on the surface. The highest concentration was obtained with M. brunneum Cb16II (1.88·107 conidia·bead−1). The highest mortality of I. ricinus nymphs under laboratory conditions, however, was achieved with encapsulated M. pemphigi X1c. Altogether, a promising Metarhizium spp. isolate that fulfills all the required needs was identified. This screening of entomopathogenic fungi has shown that in addition to virulence, cultivation and formulation aspects need to be considered to open up novel attract-and-kill formulation strategies as an option for arthropod pest control. [ABSTRACT FROM AUTHOR]