Investigation of the toxicity of ethanol extracts obtained from six different Satureja L. species on Colorado Potato Beetle, Leptinotarsa decemlineata (Say, 1824), (Coleoptera: Chrysomelidae)

Abstract

In the present study, ethanol extracts obtained from Satureja cilicica P. H. Davis, Satureja cuneifolia Ten, Satureja hortensis L., Satureja spicigera (C. Koch) Boiss., Satureja thymbra L. and Satureja montana L. were tested against on the adults and larvae of Colorado potato beetle (Leptinotarsa decemlineata (Say, 1824)). The experiments were conducted in glass Petri dishes and vacuum desiccators including 15 individual for each period with three replicates under laboratory conditions. 10, 15 and 20 mg/mL doses of ethanol extracts conducted in the Petri dishes and the desiccators showed that depending on concentration increase and duration of exposure time resulted between 2.22-100% toxic effects on the potato beetle larvae and adults. In Petri trials, the highest mortality rate was recorded as 100% for the second larval stage at the 20 mg/mL dose of S. spicigera ethanol extract after 96 hours the treatment. In desiccator experiments, the highest toxicity rate was determined as 100% for first larval stage at the 20 mg/mL dose of S. thymbra ethanol extract after 96 hours of the application. In addition to, when LD values of the ethanol extracts were taken into account the highest toxicity of adult period was determined for S. thymbra extract (LD25: 0.000, LD50: 0.010 μL/insect), the lowest toxicity was determined for S. cilicica extract (LD90: 436.020 μL/insect). The results obtained from this study suggested that the ethanol extracts of tested Satureja L. species could be used for L. decemlineata larvae and adults as bio-larvicides and insecticides.

Acaricidal, Insecticidal, and Nematicidal Efficiency of Essential Oils Isolated from the Satureja Genus

“…For example, along with acute fumigant toxicity of S. thymbra essential oil against the adults of Acanthoscelides obtectus , Ephestia. kuehniella , and Leptinotarsa decemlineata , its repellent effect on Aedes albopictus was also reported [ 22 , 23 , 24 ]. In general, there are several sub-lethal bio-efficiencies of Satureja essential oils, including repellent and antifeedant activities and adverse effects on fecundity, fertility, and life cycle.…”

“…High mortality of the first (100%), second (100%), third (95.5%), and fourth (95.5%) instar larvae and the adults (80.0%) at 20 µL/cm 2 after 96 h [24].…”

“…High mortality of the first (100.0%), second (95.5%), third (97.7%), and fourth (95.5%) instar larvae and the adults (97.7%) at 20 µL/cm 2 after 96 h [24]. S. wiedemanniana (Avé-Lall) Velen Contact toxicity (on treated filter papers) against the adult females L. pseudobrassicae.…”