Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2001-2-7
pubmed:abstractText
Plants shaded by neighbors or overhead foliage experience both a reduction in the ratio of red to far red light (R:FR), a specific cue perceived by phytochrome, and reduced photosynthetically active radiation (PAR), an essential resource. We tested the adaptive value of plasticity to crowding and to the cue and resource components of foliage shade in the annual plant Arabidopsis thaliana by exposing 36 inbred families from four natural populations to four experimental treatments: (1) high density, full sun; (2) low density, full sun; (3) low density, neutral shade; and (4) low density, low R:FR-simulated foliage shade. Genotypic selection analysis within each treatment revealed strong environmental differences in selection on plastic life-history traits. We used specific contrasts to measure plasticity to density and foliage shade, to partition responses to foliage shade into phytochrome-mediated responses to the R:FR cue and responses to PAR, and to test whether plasticity was adaptive (i.e., in the same direction as selection in each environment). Contrary to expectation, we found no evidence for adaptive plasticity to density. However, we observed both adaptive and maladaptive responses to foliage shade. In general, phytochrome-mediated plasticity to the R:FR cue of foliage shade was adaptive and counteracted maladaptive growth responses to reduced PAR. These results support the prediction that active developmental responses to environmental cues are more likely to be adaptive than are passive resource-mediated responses. Multiple regression analysis detected a few costs of adaptive plasticity and adaptive homeostasis, but such costs were infrequent and their expression depended on the environment. Thus, costs of plasticity may occasionally constrain the evolution of adaptive responses to foliage shade in Arabidopsis, but this constraint may differ among environments and is far from ubiquitous.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0014-3820
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1982-94
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Plasticity to light cues and resources in Arabidopsis thaliana: testing for adaptive value and costs.
pubmed:affiliation
Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA. Lisa_Dorn@brown.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.