Format

Send to

Choose Destination
Phytochemistry. 2010 Jul;71(10):1115-21. doi: 10.1016/j.phytochem.2010.04.014. Epub 2010 May 7.

17-Hydroxygeranyllinalool glycosides are major resistance traits of Nicotiana obtusifolia against attack from tobacco hornworm larvae.

Author information

1
Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, D-07745 Jena, Germany.

Abstract

In the Great Basin Desert, Nicotiana obtusifolia (synonymous with Nicotiana trigonophylla) and Nicotiana attenuata co-occur, but the former is frequently less attacked by larvae of the tobacco hornworm than the latter, despite having lower nicotine and trypsin protease inhibitor defenses. Glycosides of the diterpene, 17-hydroxygeranyllinalool (HGL-DTGs) have recently been found to be important defenses of N. attenuata. Total HGL-DTG levels are 5-fold higher in N. obtusifolia than in N. attenuata, and we characterize the three major HGL-DTGs purified from N. obtusifolia leaves as: 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-17-hydroxygeranyllinalool-17-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside; nicotinoside III and its malonic acid conjugates. Using APCI- and ESI-LC-MS, we also identified mono- and diacetyl-nicotinoside III and quercetin glycosides. To evaluate the defensive value of these HGL-DTGs, we used virus-induced-gene silencing to reduce the transcript levels of geranylgeranyl diphosphate synthase and total HGL-DTG levels in both species. When fed on silenced plants, larvae gained up to about two times more mass than those that fed on empty vector control plants of both species. We conclude that HGL-DTGs function as the most important direct defenses for both N. attenuata and N. obtusifolia.

PMID:
20452633
DOI:
10.1016/j.phytochem.2010.04.014
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center