Leaf herbivory and drought stress affect floral attractive and defensive traits in Nicotiana quadrivalvis.
Adaptive phenotypic plasticity allows sessile organisms such as plants to match trait expression to the particular environment they experience. Plasticity may be limited, however, by resources in the environment, by responses to prior environmental cues, or by previous interactions with other species, such as competition or herbivory. Thus, understanding the expression of plastic traits and their effects on plant performance requires evaluating trait expression in complex environments, rather than across levels of a single variable. In this study, we tested the independent and combined effects of two components of a plant's environment, herbivory and water availability, on the expression of attractive and defensive traits in Nicotiana quadrivalvis in the greenhouse. Damage and drought did not affect leaf nicotine concentrations but had additive and non-additive effects on floral attractive and defensive traits. Plants in the high water treatment produced larger flowers with more nectar than in the low water treatment. Leaf damage induced greater nectar volumes in the high water treatment only, suggesting that low water limited plastic responses to herbivore damage. Leaf damage also tended to induce higher nicotine concentrations in nectar, consistent with other studies showing that leaf damage can induce floral defenses. Our results suggest that there are separate and synergistic effects of leaf herbivory and drought on floral trait expression, and thus plasticity in response to complex environments may influence plant fitness via effects on floral visitation and defense.
Halpern
Stacey L
SL
Biology Department, Pacific University, 2043 College Way, Forest Grove, OR 97116, USA. shalpern@pacificu.edu
Adler
Lynn S
LS
Wink
Michael
M
D000818:Animals; D005247:Feeding Behavior; D035264:Flowers / Q000254:growth & development*; D006790:Host-Parasite Interactions; D018515:Plant Leaves; D018411:Spodoptera / Q000502:physiology*; D014026:Nicotiana / Q000502:physiology*; D014867:Water / Q000502:physiology*
D014867:Water
Proc Natl Acad Sci U S A. 2006 May 2;103(18):7170-4
16632610
Oecologia. 1984 Feb;61(2):208-210
28309413
Evolution. 2001 May;55(5):930-6
11430653
Oecologia. 1988 Nov;77(3):378-381
28311953
Oecologia. 2005 Sep;145(2):298-306
15959818
Am Nat. 2007 Apr;169(4):443-54
17253430
Oecologia. 1995 May;102(2):174-179
28306872
Oecologia. 2006 Jan;146(4):566-71
16328552
Am J Bot. 2005 Jan;92(1):21-6
21652380
Proc Natl Acad Sci U S A. 2009 Sep 22;106(38):16298-303
19805296
Oecologia. 2007 Apr;151(4):574-83
17180373
Proc Natl Acad Sci U S A. 2003 Nov 25;100 Suppl 2:14581-6
14530394
Ecol Lett. 2006 Aug;9(8):960-7
16913940
Oecologia. 1999 Mar;118(4):461-470
28307414
Ecology. 2006 Nov;87(11):2709-16
17168015
Am Nat. 2004 Apr;163(4):548-63
15122502
J Chem Ecol. 2007 Jan;33(1):95-103
17111219
New Phytol. 2005 Apr;166(1):149-58
15760359
Oecologia. 1997 May;110(4):493-500
28307240
Evolution. 1996 Apr;50(2):957-963
28568918
Ecol Lett. 2007 Mar;10(3):E1; discussion E2-3
17305799
Ecology. 2007 Apr;88(4):1021-9
17536717
Science. 2008 May 9;320(5877):800-3
18467590
J Evol Biol. 2003 Mar;16(2):313-23
14635870
Ecology. 2008 Feb;89(2):392-406
18409429
Am Nat. 2004 Oct;164(4):531-42
15459883
Evolution. 1991 Sep;45(6):1458-1467
28563828
Ecology. 2008 Aug;89(8):2207-17
18724731
Oecologia. 1998 Jul;115(4):531-540
28308274
Am J Bot. 2006 Apr;93(4):531-8
21646213
New Phytol. 2007;176(4):749-763
17997761
Ann Bot. 2005 Feb;95(3):431-7
15585545
Oecologia. 1997 Jul;111(3):396-403
28308135
Plant J. 2007 Mar;49(5):840-54
17316174
Annu Rev Entomol. 1998;43:195-216
15012389
Proc Natl Acad Sci U S A. 2009 Mar 24;106(12):4935-40
19251652
Evolution. 1996 Aug;50(4):1442-1453
28565718
Evolution. 1999 Aug;53(4):1105-1113
28565516
Am Nat. 2009 Feb;173(2):241-55
19140769
Science. 2008 Aug 29;321(5893):1200-2
18755975
Am J Bot. 2001 Mar;88(3):438-46
11250821
Science. 1984 Nov 2;226(4674):537-9
17821511