« Previous AbstractIdentification and assessment of hazardous compounds in drinking water    Next Abstract"Health effects of air pollutant mixtures (volatile organic compounds, particulate matter, sulfur and nitrogen oxides) - a review of the literature" »

Oecologia

Title:		Constraints on growth and allocation patterns of Silphium integrifolium (Asteraceae) caused by a cynipid gall wasp
Author(s):		Fay PA; Hartnett DC;
Address:		"Division of Biology, Kansas State University, Ackert Hall, 66506, Manhattan, KS, USA"
Journal Title:		Oecologia
Year:		1991
Volume:		88
Issue:		2
Page Number:		243 - 250
DOI:		10.1007/BF00320818
ISSN/ISBN:		1432-1939 (Electronic) 0029-8549 (Linking)
Abstract:		"Insect herbivory can have important effects on plant life histories and architecture. We quantified the impact that a cynipid gall wasp, Antistrophus silphii, had on growth, reproduction, and biomass allocation patterns of Silphium integrifolium growing in the tallgrass prairie of northeastern Kansas. Experimentally galled individual Silphium shoots (ramets) had reduced shoot growth, leaf and flower head production, and delayed flowering compared to gall-free control shoots. Gall formation completely halted normal apical growth in 65% of the shoots. Galling did not affect individual flower head weight, the numbers of achenes per flower head or achene weight. Silphium plants (genets) with a high proportion of galled shoots had lower total biomass, a lower proportion of total biomass allocated to flower heads, higher allocation to leaves, but no change in allocation to stems or rhizome. High gall densities reduced the number of flower heads per plant and shortened the time between flower head initiation and maturity. An adaptive interpretation of these results would be that the survivorship and future performance of galled Silphium may be promoted by maintaining allocation to rhizome. However, reduced shoot growth and delayed reproduction in galled Silphium may weaken its competitive ability and reduce pollination success, so that any adaptive advantage to Silphium's allocation responses to galls may be outweighed by disadvantages from its growth and flowering phenology responses. We conclude that a more parsimonious interpretation of these results is that gall-induced allocation changes are due to architectural constraints placed by galls on meristem activity, rather than to any adaptive response on the part of the plant"
Keywords:		Allocation Gall insect Life history Plant insect interactions Silphium integrifolium;
Notes:		"PubMed-not-MEDLINEFay, P A Hartnett, D C eng Germany 1991/10/01 Oecologia. 1991 Oct; 88(2):243-250. doi: 10.1007/BF00320818"