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Proc Natl Acad Sci U S A

Title:		Whiteflies interfere with indirect plant defense against spider mites in Lima bean
Author(s):		Zhang PJ; Zheng SJ; van Loon JJ; Boland W; David A; Mumm R; Dicke M;
Address:		"Laboratory of Entomology, Wageningen University, PO Box 8031, 6700 EH Wageningen, The Netherlands"
Journal Title:		Proc Natl Acad Sci U S A
Year:		2009
Volume:		20091124
Issue:		50
Page Number:		21202 - 21207
DOI:		10.1073/pnas.0907890106
ISSN/ISBN:		1091-6490 (Electronic) 0027-8424 (Print) 0027-8424 (Linking)
Abstract:		"Plants under herbivore attack are able to initiate indirect defense by synthesizing and releasing complex blends of volatiles that attract natural enemies of the herbivore. However, little is known about how plants respond to infestation by multiple herbivores, particularly if these belong to different feeding guilds. Here, we report the interference by a phloem-feeding insect, the whitefly Bemisia tabaci, with indirect plant defenses induced by spider mites (Tetranychus urticae) in Lima bean (Phaseolus lunatus) plants. Additional whitefly infestation of spider-mite infested plants resulted in a reduced attraction of predatory mites (Phytoseiulus persimilis) compared to attraction to plants infested by spider mites only. This interference is shown to result from the reduction in (E)-beta-ocimene emission from plants infested by both spider mites and whiteflies. When using exogenous salicylic acid (SA) application to mimic B. tabaci infestation, we observed similar results in behavioral and chemical analyses. Phytohormone and gene-expression analyses revealed that B. tabaci infestation, as well as SA application, inhibited spider mite-induced jasmonic acid (JA) production and reduced the expression of two JA-regulated genes, one of which encodes for the P. lunatus enzyme beta-ocimene synthase that catalyzes the synthesis of (E)-beta-ocimene. Remarkably, B. tabaci infestation concurrently inhibited SA production induced by spider mites. We therefore conclude that in dual-infested Lima bean plants the suppression of the JA signaling pathway by whitefly feeding is not due to enhanced SA levels"
Keywords:		Animals Cyclopentanes/antagonists & inhibitors Ectoparasitic Infestations/immunology Fabaceae/*immunology/parasitology Hemiptera/*pathogenicity Oxylipins/antagonists & inhibitors Salicylic Acid/pharmacology Signal Transduction/drug effects Tetranychidae/*;
Notes:		"MedlineZhang, Peng-Jun Zheng, Si-Jun van Loon, Joop J A Boland, Wilhelm David, Anja Mumm, Roland Dicke, Marcel eng Research Support, Non-U.S. Gov't 2009/12/08 Proc Natl Acad Sci U S A. 2009 Dec 15; 106(50):21202-7. doi: 10.1073/pnas.0907890106. Epub 2009 Nov 24"