Chemical composition and repellent effects of powders and essential oils of Artemisia absinthium, Melia azedarach, Trigonella foenum-graecum, and Peganum harmala on Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

Abstract

Tribolium castaneum (herbst) is one of the most damaging insect pests of stored products. The aim of this study is to assess the repellent effects of powders and essential oils (EOs) of Artemisia absinthium aerial parts, Melia azedarach fruits, Trigonella foenum-graecum, and Peganum harmala seeds on adults of T. castaneum (Herbst). The EOs were extracted by the hydrodistillation method, and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The repellency test was determined by the area preference method. The number of insects present in treated and control areas was counted after 10 min, 20 min, 30 min, 1 h, 2 h, 3 h, 4 h, and 5 h of exposure. The results obtained by GC-MS revealed that the major components of the studied EOs were camphor (36.22%) and α-thujone (30.28%) for A. absinthium EO. Caproic acid (8.63%) and ç-Caprolactone (9.44%) for M. azedarach EO; Epi-cubenol (28.78%), palmitic acid (15.07%), and Dihydroactinolide (10.84%) for T. foenum-graecum; and α -Pinene (29.38%), linoleic acid (14.00%) for P. harmala. The M. azedarach powder has the highest average repellency rate of 48.20%, followed by T. foenum-graecum (34.67%), while A. absinthium and P. harmala powders have the negatives average repellency rates (−22.10% and −16.10%, respectively). Furthermore, A. absinthium EO had the highest average repellency rate of 64.50%, followed by M. azedarach and P. harmala EOs (50.30% and 46.50%, respectively). In contrast, T. foenum-graecum EO gave 33.70% of repellency. The plants studied may prove novel biological treatments to prevent insect infestations of stored products.