Jiahui Liu1,2, Xiaojing Zhao1, Yidi Zhan1, Kang Wang1,3, Frederic Francis1,2, Yong Liu1. 1. College of Plant Protection, Shandong Agricultural University, No. 61, Daizong Road, Taian, Shandong, 271018, China. 2. Functional and Evolutionary Entomology, Terra, Gembloux Agro-Bio Tech, Liege University, Passage des Deportes 2, 5030, Gembloux, Belgium. 3. Taizhou Customs of the People's Republic of China, No. 269 Zhongxin Road, Taizhou City, Zhejiang, 318000, China.
Abstract
BACKGROUND: Semiochemical use is a promising way to reduce damages from pests by improving natural control in agro-ecosystems. The aphid alarm pheromone (E)-β-farnesene (EβF) and herbivore-induced methyl salicylate (MeSA) are two volatile cues to induce changes in aphid behavior with functional significance. Because of the limitations related to the volatility and oxidization of EβF and MeSA under natural conditions, slow release and antioxidant techniques should be developed and optimized before application. Here, a slow release alginate bead of EβF mixed with MeSA was first designed and manufactured. We hypothesized that mixture of these two semiochemicals could be effective in controlling Sitobion miscanthi in wheat crops. RESULTS: Both MeSA and EβF in alginate beads released stably and continuously for at least 15 days in laboratory, whereas EβF in paraffin oil and pure MeSA did only for 2 and 7 days respectively. In 2018 field experiments, EβF and MeSA alone or in association significantly decreased abundances of alate and apterous. The increased abundance of mummified aphids enhanced by higher parasitism rates was observed by using EβF and MeSA in association, with also significant reduction of apterous abundance, more than EβF or MeSA alone. In 2019, the mixture of EβF and MeSA treated plots significantly decreased the alate and apterous aphid abundances with higher parasitism rates compared with the control. CONCLUSIONS: The new slow release alginate bead of a mixture of EβF with MeSA could be the most efficient formulation to control S. miscanthi population by attracting parasitoids in the wheat agro-ecosystem. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
BACKGROUND: Semiochemical use is a promising way to reduce damages from pests by improving natural control in agro-ecosystems. The aphid alarm pheromone (E)-β-farnesene (EβF) and herbivore-induced methyl salicylate (MeSA) are two volatile cues to induce changes in aphid behavior with functional significance. Because of the limitations related to the volatility and oxidization of EβF and MeSA under natural conditions, slow release and antioxidant techniques should be developed and optimized before application. Here, a slow release alginate bead of EβF mixed with MeSA was first designed and manufactured. We hypothesized that mixture of these two semiochemicals could be effective in controlling Sitobion miscanthi in wheat crops. RESULTS: Both MeSA and EβF in alginate beads released stably and continuously for at least 15 days in laboratory, whereas EβF in paraffin oil and pure MeSA did only for 2 and 7 days respectively. In 2018 field experiments, EβF and MeSA alone or in association significantly decreased abundances of alate and apterous. The increased abundance of mummified aphids enhanced by higher parasitism rates was observed by using EβF and MeSA in association, with also significant reduction of apterous abundance, more than EβF or MeSA alone. In 2019, the mixture of EβF and MeSA treated plots significantly decreased the alate and apterous aphid abundances with higher parasitism rates compared with the control. CONCLUSIONS: The new slow release alginate bead of a mixture of EβF with MeSA could be the most efficient formulation to control S. miscanthi population by attracting parasitoids in the wheat agro-ecosystem. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.