Toxicity property of clove oil (Syzygium aromaticum L.) and rice grain protection against Rhyzopertha Dominica (Fabricius) and Sitophilus zeamais Motschulsky

Abstract

© 2019 Association of Agricultural Technology in Southeast Asia. All Rights Reserved. Rhyzopertha Dominica and Sitophilus zeamais caused considerable damage on rice stored grains. These stored insects are normally controlled during storage mainly by synthetic insecticides for grain protection and fumigation. Plant extract was highly conducted with effectiveness against stored grain insects and can be an alternative application which is safety to natural environment and consumers. This study investigated the application of clove oil (Syzygium aromaticum L.) by grain treatment as well as effects to their insecticide activity, inhibition progeny production, and grain damage (weight loss) as compared with chlorpyrifos under laboratory. The results showed that clove oil coating at 200 µL/L after 7 days of application had performed the mortality percentage of R. Dominica and S. zeamais at 99.33% and 95.33%, whereas chlorpyrifos was showed mortality percentage at 66.00% and 100%, respectively. The study indicated that this insecticide was lower effective to kill R. Dominica than clove oil, but all of them were still effective to kill S. zeamais. For F1 inhibition emergence, the clove oil inhibited adult emergence both R. Dominica and S. zeamais, whereas chlorpyrifos was highly inhibited to the emerged adults of R. Dominica than S. zeamais adults. Weight loss and frass production of grain coated with clove oil showed the greater in S. zeamais than that in R. Dominica. This attributed to more susceptible of R. Dominica to clove oil than S. zeamais. Hence, grain coating with clove oil is an alternative method for promising as seed protectants from R. Dominica and S. zeamais in warehouse in the future. Clove oil is safety, environmental-friendly, and reduces the use of synthetic insecticide. However, this method should be further studied in terms of reasonable application such as economic-value consideration.