Progeny of the maize weevil, Sitophilus zeamais, is affected by parental exposure to clove and cinnamon essential oils.

The interest in and utilization of botanical insecticides, particularly essential oils, has become increasingly relevant to the control of insect pests. However, the potential ecotoxicological risks or flaws (including sublethal effects on the targeted pest generation and its subsequent progeny) of this pest control tool have been neglected frequently. Here, we evaluated the effects of sublethal exposure to clove, Syzygium aromaticum (L.) Merrill & Perry ( Myrtaceae), and cinnamon, Cinnamomum verum J. Presl ( Lauraceae), essential oils on adult (F0) maize weevils, Sitophilus zeamais Motschulsky ( Coleoptera: Curculionidae), and the physiology (e.g., body mass, respirometry, and grain consumption) and population dynamics (e.g., daily emergence and sex ratio) of their progeny. Longevities of the parents were negatively affected by the essential oils in a concentration-dependent manner. Parental sublethal exposure to clove oil (0.17 μl cm−2) accelerated offspring emergence but delayed the emergence of females compared to males. Parents that were sublethally exposed to clove (0.17 μl cm−2) or cinnamon (0.35 μl cm−2) essential oils produced heavier offspring. Parental sublethal exposure to cinnamon essential oil accelerated offspring emergence (at 0.70 μl cm−2), delayed female emergence (at 0.17 μl cm−2), and enhanced grain consumption (at 0.35 and 0.70 μl cm−2) of the progeny. Thus, our findings indicate that sublethal exposure to clove and cinnamon essential oils is capable of promoting transgenerational effects in S. zeamais that can negatively impact the control efficacy of such products. [ABSTRACT FROM AUTHOR]