INVESTIGADORES
RUBIO Gerardo
artículos
Título:
Root gravitropism and belowground competition among neighboring plants: a modeling approach
Autor/es:
RUBIO G., T. WALK, Z. GE, X. YAN, H. LIAO, J.P. LYNCH
Revista:
ANNALS OF BOTANY
Editorial:
OXFORD UNIV PRESS
Referencias:
Año: 2001 vol. 88 p. 929 - 940
ISSN:
0305-7364
Resumen:
Competition for nutrients among neighbouring roots occurs when their individual depletion volumes overlap,causing a reduction in nutrient uptake. By exploring di€erent spatial niches, plants with contrasting root architecturemay reduce the extent of competition among neighbouring root systems. The main objectives of this study were: (1) toevaluate the impact of root architecture on competition for phosphorus among neighbouring plants; and (2) tocompare the magnitude of competition among roots of the same plant vs. roots of neighbouring plants. SimRoot,adynamic geometric model, was used to simulate common bean root growth and to compare the overlap of depletionvolumes. By varying the gravitropism of basal roots, we simulated three distinct root architectures: shallow,intermediate and deep, corresponding to observed genetic variation for root architecture in this species. Combina-tions of roots having the same architecture resulted in more intense inter-plant competition. Among them, the deep-deep combination had the most intense competition. Competition between deep root systems and shallow rootsystems was only half that of deep root systems competing with other deep root systems. Inter-plant root competitionincreased as soil di€usivity increased and the distance among plants decreased. In heterogeneous soils, co-localizationof soil resources and roots was more important in determining resource uptake than inter-plant root competition.Competition among roots of the same plant was three- to ®ve-times greater than competition among roots ofneighbouring plants. Genetic variation for root architecture in common bean may be related to adaptation to diversecompetitive environments.