How to be sweet? Extra floral nectar allocation by Gossypium hirsutum fits optimal defense theory predictions

TY - JOUR

T1 - How to be sweet? Extra floral nectar allocation by Gossypium hirsutum fits optimal defense theory predictions

AU - Wäckers, F.L.

AU - Bonifay, C.

N1 - Reporting year: 2004 Metis note: 3405; CTE; MTI; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2004/Wackers_ea_3405.pdf

PY - 2004

Y1 - 2004

N2 - Plants employ nectar for two distinct functions. Floral nectar has traditionally been viewed in the context of pollination. Extrafloral nectar on the other hand, can act as an indirect defense, allowing the plant to recruit predators and parasitoids. Whereas this makes for a clear-cut categorization, in reality the functions may not be so discrete. Extrafloral nectar may serve a role in pollination, while floral nectar can be utilized by predators and parasitoids and thus can contribute to plant defense. Here we use the optimal defense theory to generate predictions with respect to allocation patterns of defensive nectar. These predictions are then tested using novel data on the production patterns of bracteal and foliar nectar in cotton, Gossypium hirsutum. Bracteal nectar production shows a distinct peak on the day of anthesis, followed by a prolonged secretion during fruit maturation. This suggests that bracteal nectaries function in pollination as well as defense. Constitutive nectar production at the bracteal nectaries exceeds foliar nectar secretion by a factor of between 80 and 110. Whereas nectar production at foliar nectaries is induced following herbivore damage to leaves, bracteal nectar production is not induced in response to fruit dama [KEYWORDS: bracteal nectar; cotton; extrafloral nectar; foliar nectar; Gossypium hirsutum; herbivore refuge; indirect defense; multiple functions; nectar allocation; optimal defense theory; pollination]

AB - Plants employ nectar for two distinct functions. Floral nectar has traditionally been viewed in the context of pollination. Extrafloral nectar on the other hand, can act as an indirect defense, allowing the plant to recruit predators and parasitoids. Whereas this makes for a clear-cut categorization, in reality the functions may not be so discrete. Extrafloral nectar may serve a role in pollination, while floral nectar can be utilized by predators and parasitoids and thus can contribute to plant defense. Here we use the optimal defense theory to generate predictions with respect to allocation patterns of defensive nectar. These predictions are then tested using novel data on the production patterns of bracteal and foliar nectar in cotton, Gossypium hirsutum. Bracteal nectar production shows a distinct peak on the day of anthesis, followed by a prolonged secretion during fruit maturation. This suggests that bracteal nectaries function in pollination as well as defense. Constitutive nectar production at the bracteal nectaries exceeds foliar nectar secretion by a factor of between 80 and 110. Whereas nectar production at foliar nectaries is induced following herbivore damage to leaves, bracteal nectar production is not induced in response to fruit dama [KEYWORDS: bracteal nectar; cotton; extrafloral nectar; foliar nectar; Gossypium hirsutum; herbivore refuge; indirect defense; multiple functions; nectar allocation; optimal defense theory; pollination]

U2 - 10.1890/03-0422

DO - 10.1890/03-0422

M3 - Article

SN - 0012-9658

VL - 85

SP - 1512

EP - 1518

JO - Ecology

JF - Ecology

IS - 6

ER -