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Background: Ticks and tick-borne diseases are a severe economic and public-health problem for cattle producers. The emergence of acaricide resistance to synthetic chemical treatments has prompted interest in developing alternative tickcontrol methods.Aim: The main objective of the current research was to identify the chemical structure of Carthamus tinctorius and Nasturtium officinale seed oils and to assess their anti-tick properties against Hyalomma scupense ticks both alone and in combination (1:1).Methods: Analytical methods were used to analyze the chemical components. For in vitro assays, adults of H. scupense were immersed in C. tinctorius and N. officinale seed oils at 100, 125, 200, and 300 mg/ml concentrations; for 5 minutes. Larvae of H. scupense were dipped in 25, 50, 100, 125, 200, and 300 mg/ml doses of seed oils; the mortality percentage was determined after 24 hours.Results: The seed oil safflower was mainly composed of linoleic acid (84.48%), followed by palmitic acid (6.54%) and stearic acid (3.77%). Meanwhile, watercress seed oil was mainly composed of linolenic acid (50.78%), gondoic acid (13.57%), linoleic acid (10.58%), palmitic acid (8.02%), and erucidic acid (6.62%). The Adults Immersion Test showed the sensitivity of ticks to C. tinctorius and N. officinale seed oil: C. tinctorius seed oil caused (95%) mortality of H. scupense at 300 mg/ml, while N. officinale seed oil induced (88.68%) mortality at the same concentration. At a 200 mg/ml concentration, C. tinctorius and N. officinale oil combined caused 100% mortality. Tested oils showed larvicidal efficacy. LC50 values for C. tinctorius and N. officinale seed oils were 84.16 and 61.78 mg/ml, respectively, in 24 hours. LC50 value of oils association (50% C. tinctorius: 50% N. officinale) was 47.96 mg/ml. The mixture of seed oils from two plants tested against H. scupense larvae and adult females at a 1:1 ratio showed synergistic interaction.Conclusion: Seed oils tested alone, and the mixture could be used as an alternative solution in the fight against ticks.

International audience; Enniatins are emerging mycotoxins produced by Fusarium species. They are frequently found as contaminants in cereal grains in recent years. The synthesis of these secondary metabolites is often a response to biotic and abiotic stresses. Therefore, the introduction of fungicides into the environment of toxigenic fungi can lead to an increase in mycotoxin accumulation. The search for molecules with both antifungal and antimycotoxigenic activities is a challenge to preserve food safety. Essential oils (EOs) have a promising potential as natural fungicides and should be used both to control fungi and/or their mycotoxin production. In the present work, we extracted the essential oil of Tunisian Thymus capitatus and tested its effect in vitro on two enniatin-producing Fusarium strains when placed in contact with the mycelium in solid medium or used as a fumigant. In agar medium, contact tests measured with two different sets of EOs for a strain of Fusarium avenaceum provided an IC 5O of 0.05 µL EO mL-1. For another strain of Fusarium sp. it was found an IC 50 of 0.08 µL EO mL-1. Fungistatic activity induced no overproduction of enniatins and in contrast, decreases of 55% were found in some samples. Volatile components diffusing in a sealed container also had fungistatic activity that was both dose (5 to 25 µL 1.5 L-1) and time (6 to 24 days) dependent. No fungal acclimation to the EOs and no persistent effect of the EOs were observed, but the decrease in protective effect with increasing incubation time was probably due to EOs alterations.