Herbivore attack in Casearia nitida influenced by plant ontogenetic variation in foliage quality and plant architecture.
Traits influencing plant quality as food and/or shelter for herbivores may change during plant ontogeny, and as a consequence, influence the amount of herbivory that plants receive as they develop. In this study, differences in herbivore density and herbivory were evaluated for two ontogenetic stages of the tropical tree Casearia nitida. To assess plant ontogenetic differences in foliage quality as food for herbivores, nutritional and defensive traits were evaluated in saplings and reproductive trees. Predatory arthropods were quantified and the foraging preferences of a parasitoid wasp of the genus Zacremnops were assessed. In addition, survival rates of lepidopteran herbivores (Geometridae) were evaluated experimentally. Herbivore density was three times higher and herbivory was 66% greater in saplings than in reproductive trees. Accordingly, concentrations of total foliar phenolics were higher in reproductive trees than in saplings, whereas leaf toughness, water and nitrogen concentration did not vary between ontogenetic stages. Survival rates of lepidopteran larvae exposed to natural enemies were equivalent in reproductive trees and saplings. Given the greater herbivore density on saplings, equal survival rates implied a greater foraging effort of predators on reproductive trees. Furthermore, observed foraging of parasitoid wasps was restricted to reproductive trees. I propose that herbivore density, and as a consequence, leaf damage were lower in reproductive trees than in saplings due to both traits influencing food quality, and architectural or unmeasured indirect defensive traits influencing foraging preference of natural enemies of herbivores.
Boege
Karina
K
Department of Biology, University of Missouri-St. Louis., One University Drive, St. Louis, MO 63121, USA. kboege@servidor.unam.mx
D000818:Animals; D006790:Host-Parasite Interactions; D007313:Insecta / Q000502:physiology*; D007814:Larva / Q000502:physiology; D008800:Mexico; D009584:Nitrogen / Q000032:analysis; D010636:Phenols / Q000032:analysis; D018515:Plant Leaves / Q000254:growth & development / Q000469:parasitology; D018521:Plant Physiological Phenomena; D011156:Population Density; D011157:Population Dynamics; D011235:Predatory Behavior; D012098:Reproduction; D031308:Salicaceae / Q000737:chemistry / Q000254:growth & development / Q000469:parasitology*; D013634:Tannins / Q000032:analysis
D010636:Phenols; D013634:Tannins; D009584:Nitrogen
Proc Natl Acad Sci U S A. 2003 Jul 8;100(14):8304-7
12832618
Plant Physiol. 1999 Oct;121(2):325-32
10517823
Oecologia. 1988 Jul;76(2):278-282
28312207
Oecologia. 1987 Sep;73(3):334-337
28311513
Oecologia. 2001 Oct;129(2):253-260
28547604
J Nat Prod. 2004 Mar;67(3):316-21
15043402
Oecologia. 2001 Sep;129(1):87-97
28547071
Oecologia. 1985 Feb;65(3):319-323
28310435
J Agric Food Chem. 2002 Mar 27;50(7):1785-90
11902913
Am J Bot. 2002 Nov;89(11):1847-51
21665613
J Exp Mar Bio Ecol. 2001 Mar 30;258(1):65-86
11239626
Oecologia. 1984 Jun;62(3):387-392
28310893
Oecologia. 1998 Jan;113(3):400-405
28307825
Oecologia. 1994 Mar;97(2):186-192
28313927
Oecologia. 2004 Mar;139(1):1-10
14872336
Phytochemistry. 2003 May;63(1):109-13
12657305
J Chem Ecol. 2001 Oct;27(10):1943-51
11710603
Oecologia. 1989 May;79(2):189-192
28312854
Science. 1983 Dec 2;222(4627):1023-5
17776247
Science. 1990 Nov 16;250(4983):923-30
17746915
Plant J. 2004 Feb;37(4):603-16
14756770