O-acyl sugars protect a wild tobacco from both native fungal pathogens and a specialist herbivore

• Verfasst von: Luu, Van Thi [VerfasserIn]
• Verfasst von: Gaquerel, Emmanuel [VerfasserIn]
• Titel: O-acyl sugars protect a wild tobacco from both native fungal pathogens and a specialist herbivore
• Verf.angabe: Van Thi Luu, Alexander Weinhold, Chhana Ullah, Stefanie Dressel, Matthias Schoettner, Klaus Gase, Emmanuel Gaquerel, Shuqing Xu, and Ian T. Baldwin
• E-Jahr: 2017
• Jahr: 08 March 2017
• Umfang: 17 S.
• Illustrationen: Illustrationen
• Teil: volume:174
• Teil: year:2017
• Teil: number:1
• Teil: pages:370-386
• Teil: extent:17
• Fussnoten: Gesehen am 27.09.2018
• Titel Quelle: Enthalten in: Plant physiology
• Ort Quelle: Rockville, Md. : Soc., 1926
• Jahr Quelle: 2017
• Band/Heft Quelle: 174(2017), 1, Seite 370-386
• ISSN Quelle: 1532-2548
• DOI: doi:10.1104/pp.16.01904
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1581364164

Abstract

O-Acyl sugars (O-AS) are abundant trichome-specific metabolites that function as indirect defenses against herbivores of the wild tobacco Nicotiana attenuata; whether they also function as generalized direct defenses against herbivores and pathogens remains unknown. We characterized natural variation in O-AS among 26 accessions and examined their influence on two native fungal pathogens, Fusarium brachygibbosum U4 and Alternaria sp. U10, and the specialist herbivore Manduca sexta. At least 15 different O-AS structures belonging to three classes were found in N. attenuata leaves. A 3-fold quantitative variation in total leaf O-AS was found among the natural accessions. Experiments with natural accessions and crosses between high- and low-O-AS accessions revealed that total O-AS levels were associated with resistance against herbivores and pathogens. Removing O-AS from the leaf surface increased M. sexta growth rate and plant fungal susceptibility. O-AS supplementation in artificial diets and germination medium reduced M. sexta growth and fungal spore germination, respectively. Finally, silencing the expression of a putative branched-chain α-ketoacid dehydrogenase E1 β-subunit-encoding gene (NaBCKDE1B) in the trichomes reduced total leaf O-AS by 20% to 30% and increased susceptibility to Fusarium pathogens. We conclude that O-AS function as direct defenses to protect plants from attack by both native pathogenic fungi and a specialist herbivore and infer that their diversification is likely shaped by the functional interactions among these biotic stresses.