Suites of root traits differ between annual and perennial species growing in the field.

ROUMET C., URCELAY C., DÍAZ S.

NEW PHYTOLOGIST

Blackwell plublishing

Año: 2006 p. 999999 - 999999

0028-646X

We tested whether root traits associated with resource acquisition and conservation differed between life histories (annuals, perennials) and families (Fabaceae, Asteraceae, Poaceae). We measured root topology, morphology, chemistry and mycorrhizal colonisation on whole root systems of 18 field-grown herbaceous species grown and harvested in central Argentina. Annuals differed from perennials in several root traits important in resource uptake and conservation. They exhibited higher specific root length (SRL), nitrogen concentration (RNC) and mycorrhizal colonisation but had lower tissue density (RTD) than perennials. They did not differ in topology or construction cost. These differences were consistent among families. Families differed only in few traits known to be strongly associated to certain lineages such as root topology and nitrogen concentration. There was a strong parallel between root traits and analogous leaf traits described in the literature for annuals and perennials. Our results suggest the existence at the root level of an acquisitive vs. conservative syndrome consistent among families, similar to which has previously been reported for aboveground traits.   Key words: Annuals, Argentina, mycorrhizas, perennials, plant functional traits, root morphology, root