Involvement of sweet pepper Ca LOX2 in jasmonate-dependent induced defence against Western flower thrips  

作　　者：Sandeep J Sarde Klaas Bouwmeester Jhon Venegas-Molina Anja David Wilhelm Boland Marcel Dicke 

机构地区：[1]Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA Wageningen, The Netherlands [2]Laboratory of Phytopathology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands [3]Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knoll-Straβe 8, D-07745 Jena, Germany

出　　处：《Journal of Integrative Plant Biology》2019年第10期1085-1098,共14页植物学报（英文版）

基　　金：partly financed by the Netherlands Organisation for Scientific Research (NWO) and partly by the breeding companies Keygene, Syngenta and East West Seeds

摘　　要：Insect herbivory can seriously hinder plant performance and reduce crop yield. Thrips are minute cell-content-feeding insects that are important vectors of viral plant pathogens, and are serious crop pests. We investigated the role of a sweet pepper (Capsicum annuum) lipoxygenase gene, CaLOX2, in the defense of pepper plants against Western flower thrips (Frankliniella occidentalis). This was done through a combination of in-silico, transcrip-tional, behavioral andchemicalanalyses.Our datashowthat CaLOX2 is involved in jasmonic acid (JA) biosynthesis and mediates plant resistance. Expression of the JA-related marker genes, CaLOX2 and CaPIN II, was induced by thrips feeding. Silencing of CaLOX2 in pepper plants through virus-induced gene silencing (VIGS) resulted in low levels of CaLOX2 transcripts, as well as significant reduction in the accumulation of JA, and its derivatives, upon thrips feeding compared to control plants. CaLOX2-silenced pepper plants exhibited enhanced susceptibility to thrips. This indicates that CaLOX2 mediates JA-dependent signaling, resulting in defenseagainstthrips. Furthermore,exogenous application of JA to pepper plants increased plant resistance to thrips, constrained thrips population development and made plants less attractive to thrips. Thus, a multidisciplinary approach shows that an intact lipoxygenase pathway mediates various components of sweet pepper defense against F. occidentalis.Insect herbivory can seriously hinder plant performance and reduce crop yield. Thrips are minute cell-content-feeding insects that are important vectors of viral plant pathogens, and are serious crop pests. We investigated the role of a sweet pepper(Capsicum annuum)lipoxygenase gene, Ca LOX2, in the defense of pepper plants against Western flower thrips(Frankliniella occidentalis).This was done through a combination of in-silico, transcriptional, behavioral and chemical analyses. Our data show that Ca LOX2 is involved in jasmonic acid(JA) biosynthesis and mediates plant resistance. Expression of the JA-related marker genes, Ca LOX2 and Ca PIN II, was induced by thrips feeding. Silencing of Ca LOX2 in pepper plants through virusinduced gene silencing(VIGS) resulted in low levels of Ca LOX2 transcripts, as well as significant reduction in theaccumulation of JA, and its derivatives, upon thrips feeding compared to control plants. Ca LOX2-silenced pepper plants exhibited enhanced susceptibility to thrips. This indicates that Ca LOX2 mediates JA-dependent signaling, resulting in defense against thrips. Furthermore, exogenous application of JA to pepper plants increased plant resistance to thrips,constrained thrips population development and made plants less attractive to thrips. Thus, a multidisciplinary approach shows that an intact lipoxygenase pathway mediates various components of sweet pepper defense against F. occidentalis.

关 键 词：Western FLOWER THRIPS SWEET PEPPER CaLOX2 JASMONATE 

分 类 号：Q[生物学]