Investigation of Insecticidal Effects of Some Plant Seed Oils on Adults of Acanthoscelides obtectus (Say, 1831) (Coleoptera: Chrysomelidae)
8th International Eurasian Conference on Biological and Chemical Sciences (EurasianBioChem 2025) , Ankara, Türkiye, 17 - 19 Aralık 2025, ss.145-146, (Özet Bildiri)
- Yayın Türü: Bildiri / Özet Bildiri
- Basıldığı Şehir: Ankara
- Basıldığı Ülke: Türkiye
- Sayfa Sayıları: ss.145-146
- Süleyman Demirel Üniversitesi Adresli: Evet
Özet
Legumes are highly susceptible to post-harvest insect damage, which can reduce seed quality, weight, and
germination. Acanthoscelides obtectus (Say, 1831) is a major pest of stored beans and other legumes. While
chemical insecticides are commonly used, concerns about residues and environmental impact necessitate safer
alternatives. Plant-derived fixed oils represent a promising natural control strategy. This study evaluated the
insecticidal effects of Calendula officinalis oil and Silybum marianum oil on adult A. obtectus under controlled
laboratory conditions. Experiments were conducted at 24 ± 1°C and 27 ± 1°C with 65 ± 5% relative humidity in
temperature-controlled incubators.. Four different doses (100, 150, 200, and 250 μL) were applied in four
replicates, each consisting of 20 adult individuals, and mortality was monitored until all individuals in the control
groups had died. LT₅₀ values were calculated to quantify the speed of lethal effects. Results showed clear dose–
response and temperature–dependent patterns. At 24 °C, Calendula officinalis oil exhibited rapid mortality,
particularly at 200–250 μL, whereas Silybum marianum oil showed moderate efficacy. At 27 °C, mortality
increased for both oils, with Calendula officinalis oil consistently producing the fastest lethal effect across all
doses. Silybum marianum oil’s activity at 27 °C increased at higher doses (specifically at 150 μL and higher doses)
but remained low at 100 μL. These findings demonstrate that elevated temperature enhances insecticidal
performance and that Calendula officinalis oil is more potent than Silybum marianum oil under all tested
conditions. Overall, high-dose applications of Calendula officinalis oil produced the lowest LT₅₀ values, indicating
its potential as a rapid-acting natural agent for the management of A. obtectus in stored legumes.