The effect of phosphorus on cluster-root formation and functioning of Embothrium coccineum (R. et J. Forst.)

Delgado M.; Zuniga-Feest, A; Alvear, M; Borie, F

Abstract

Embothrium coccineum (R. et J. Forst.) is a Proteaceae species from the southern part of South America. South-central Chilean soils are younger and contain more phosphorus (P) than soils in Australia and South Africa, where Proteaceae are common. Phosphorus deficiency is the main factor promoting cluster-root formation in Proteaceae. It is not known, however, whether this also applies to E. coccineum, which grows on soils with higher P content. Four-month-old seedlings were grown for 4 weeks in hydroponic cultures with 1 mu M P or 50 mu M P. The number of cluster roots, relative height increment, biomass distribution, cluster root/total root biomass ratio, foliar P concentration, root acid phosphatase activity and root carboxylate-exudation rates were determined. Seedlings growing at 50 mu M P showed a 10-, 1.3- and 3.3-fold greater increase in relative height, total dry mass and foliar P concentration, respectively, compared with those grown at1 mu M P. However, seedlings grown at 1 mu M P showed a 5-, 16-, 1.7- and 1.3-fold greater number of cluster roots, cluster root/total root biomass ratio, phosphatase activity and total carboxylate exudation, respectively, as compared with those grown at 50 mu M P. A low P supply promotes the initiation, growth and metabolic activity of cluster roots which is in accordance with reports on Proteaceae species occurring in ancient and highly weathered soils.

Más información

Título según WOS: The effect of phosphorus on cluster-root formation and functioning of Embothrium coccineum (R. et J. Forst.)
Título según SCOPUS: The effect of phosphorus on cluster-root formation and functioning of Embothrium coccineum (R. et J. Forst.)
Título de la Revista: PLANT AND SOIL
Volumen: 373
Número: 01-feb
Editorial: Springer
Fecha de publicación: 2013
Página de inicio: 765
Página final: 773
Idioma: English
URL: http://link.springer.com/10.1007/s11104-013-1829-3
DOI:

10.1007/s11104-013-1829-3

Notas: ISI, SCOPUS