bioassays were conducted to assess the contact toxicity of two plant essential oils against adults of sitophilus granarius (l.) and tribolium confusum jacquelin du val. essential oils were extracted from seeds of carum copticum l. and cuminum cyminum l. contact toxicity was assessed by topical application and adult mortality was counted 1, 2, 6 and 24 h after exposure. bioassays were carried ou...