| Title: | Trading direct for indirect defense? Phytochrome B inactivation in tomato attenuates direct anti-herbivore defenses whilst enhancing volatile-mediated attraction of predators |
| Author(s): | Cortes LE; Weldegergis BT; Boccalandro HE; Dicke M; Ballare CL; |
| Address: | "IFEVA, Consejo Nacional de Investigaciones Cientificas y Tecnicas - Universidad de Buenos Aires, Ave. San Martin 4453, C1417DSE, Buenos Aires, Argentina. Instituto de Biologia Agricola de Mendoza, Consejo Nacional de Investigaciones Cientificas y Tecnicas - Universidad Nacional de Cuyo, Almirante Brown 500, Lujan de Cuyo, 5500, Mendoza, Argentina. Laboratory of Entomology, Wageningen University, PO Box 16, NL-6700, AA Wageningen, the Netherlands. IIB-INTECH, Consejo Nacional de Investigaciones Cientificas y Tecnicas - Universidad Nacional de San Martin, B1650HMP, Buenos Aires, Argentina" |
| ISSN/ISBN: | 1469-8137 (Electronic) 0028-646X (Linking) |
| Abstract: | "Under conditions of competition for light, which lead to the inactivation of the photoreceptor phytochrome B (phyB), the growth of shade-intolerant plants is promoted and the accumulation of direct anti-herbivore defenses is down-regulated. Little is known about the effects of phyB on emissions of volatile organic compounds (VOCs), which play a major role as informational cues in indirect defense. We investigated the effects of phyB on direct and indirect defenses in tomato (Solanum lycopersicum) using two complementary approaches to inactivate phyB: illumination with a low red to far-red ratio, simulating competition, and mutation of the two PHYB genes present in the tomato genome. Inactivation of phyB resulted in low levels of constitutive defenses and down-regulation of direct defenses induced by methyl jasmonate (MeJA). Interestingly, phyB inactivation also had large effects on the blends of VOCs induced by MeJA. Moreover, in two-choice bioassays using MeJA-induced plants, the predatory mirid bug Macrolophus pygmaeus preferred VOCs from plants in which phyB was inactivated over VOCs from control plants. These results suggest that, in addition to repressing direct defense, phyB inactivation has consequences for VOC-mediated tritrophic interactions in canopies, presumably attracting predators to less defended plants, where they are likely to find more abundant prey" |
| Keywords: | "Animals Cyclopentanes/pharmacology Discriminant Analysis Gene Expression Regulation, Plant/drug effects *Herbivory Least-Squares Analysis Lepidoptera/physiology Solanum lycopersicum/genetics/immunology/*metabolism/*parasitology Oxylipins/pharmacology Phyt;" |
| Notes: | "MedlineCortes, Leandro E Weldegergis, Berhane T Boccalandro, Hernan E Dicke, Marcel Ballare, Carlos L eng England 2016/10/01 New Phytol. 2016 Dec; 212(4):1057-1071. doi: 10.1111/nph.14210. Epub 2016 Sep 30" |
