|J Integr Plant Biol, 58 (7): 656-668, Research Article|
|Shifting Nicotiana attenuata's diurnal rhythm does not alter its resistance to the specialist herbivore Manduca sexta|
|1Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
2Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
3German Centre for Integrative Biodiversity Research (iDiv), Leipzig, Germany †Current address: Ecology, Department of Biology, University of Konstanz, Universitässtrasse 10, D 78457 Konstanz, Germany, ‡Current address: KWS SAAT AG, Grimsehlstrasse 31, Postfach 1463, 37555 Einbeck, Germany, §Current address: Center for Genome Engineering, Institute of Basic Science, Daejeon, Korea
Arabidopsis thaliana plants are less resistant to attack by the generalist lepidopteran herbivore Trichoplusia ni when plants and herbivores are entrained to opposite, versus identical diurnal cycles and tested under constant conditions. This effect is associated with circadian fluctuations in levels of jasmonic acid, the transcription factor MYC2, and glucosinolate contents in leaves. We tested whether a similar effect could be observed in a different plant–herbivore system: the wild tobacco Nicotiana attenuata and its co-evolved specialist herbivore, Manduca sexta. We measured larval growth on plants under both constant and diurnal conditions following identical or opposite entrainment, profiled the metabolome of attacked leaf tissue, quantified specific metabolites known to reduce M. sexta growth, and monitored M. sexta feeding activity under all experimental conditions. Entrainment did not consistently affect M. sexta growth or plant defense induction. However, both were reduced under constant dark conditions, as was M. sexta feeding activity. Our data indicate that the response induced by M. sexta in N. attenuata is robust to diurnal cues and independent of plant or herbivore entrainment. We propose that while the patterns of constitutive or general damage-induced defense may undergo circadian fluctuation, the orchestration of specific induced responses is more complex.
|Received: 01 October 2015 Published: 23 December 2015|
|© 2016 Institute of Botany, Chinese Academy of Sciences|