Species-specific effects on salicylic acid content and subsequent Myzus persicae (Sulzer) performance by three phloem-sucking insects infesting Nicotiana tabacum L.

Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) nymphs, when feeding on tobacco, generate changes that have negative systemic effects on the aphid Myzus persicae. To determine whether differences exist among defense responses induced by B. tabaci MEAM1, the whitefly Trialeurodes vaporariorum, and M. persicae, we compared salicylic acid (SA) contents in tobacco plants infested by adults and nymphs of these three species, as well as their effect on subsequently colonizing M. persicae. Plants infested with B. tabaci MEAM1 nymphs had 19.1- and 10.2-fold higher local and systemic SA levels, respectively, than the control. Infestation with T. vaporariorum caused a smaller (4.4- and 2.3-fold, respectively) increase. Nymphs of either whitefly species had significantly greater effects on SA levels than adults. SA levels in M. persicae-infested plants were 3.0- and 1.2-fold higher than in the control. Pre-infestation with B. tabaci MEAM1 nymphs significantly reduced M. persicae survival and fecundity, while T. vaporariorum nymphs reduced survival but had no effect on fecundity compared with the uninfested control. Pre-infestation with M. persicae or whitefly adults had no obvious local or systemic effects on subsequent M. persicae. The SA pathway may be a core B. tabaci MEAM1-induced defense against aphids in tobacco.