Regarding the inefficiency of prevalent control methods and their incompatibility with environmental concerns to control the grapevine cicada, Psalmocharias alhageos (Kolenati) (Hemiptera: Cicadidae), which has lately become a major pest by invading grape vineyards in Middle Eastern, there is a serious need to find suitable and effective alternative control measures. While the nymphal stage of this species inflicts significant root damage and resides in subterranean habitats, entomopathogenic fungi (EPF) are considered one of the potent groups that can effectively manage this pest as they have shown great potential against an extensive array of soil-dwelling pests. Thus, the current study aimed to assess the efficacy of three EPF species, Beauveria bassiana, Beauveria varroae, and Metarhizium anisopliae, against the nymphal stage of the grapevine cicada. The highest virulence was achieved by M. anisopliae with an LC50 value of 1 × 10 6 conidia/ml, followed by B. bassiana with an LC50 of 7.2 × 106 conidia/ml in the laboratory petri dish assay. In the soil column assay, the greatest efficacy against nymphs was recorded for M. anisopliae at the highest concentration tested (1 × 10 8 conidia/ml) causing 75% cumulative mortality. Soil type significantly influenced the activity of M. anisopliae against P. alhageos in a way that nymphal mortality was higher in clay loam (>80) and loam soil than in sandy loam, respectively. When tested at temperatures of 20, 25, and 30 °C, M. anisopliae induced the highest mortality at 20˚C (>90%) and the lowest at 30 °C (>35%). When applied to soil pots under semi-field conditions in a vineyard, M. anisopliae was recorded as the most virulent species among all EPF tested by producing 65% mortality at the concentration of 1 × 10 8 conidia/ml. Respecting our assessments of pure cultures of EPF holds promise for the management of P. alhageos. Nevertheless, future extensive evaluations of these microbial agents, especially M. anisopliae, must comprehensively understand their potential applications in the field and determine their compatibility for integration with other complementary tools

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