Explaining the coexistence of N$_2$-fixing and non-fixing rhizobia in the legume-Rhizobium symbiosis using mathematical modelling and experiments

DAMIAN KNOPOFF; TORRES GERMAN; TURNER CRISTINA; MARCO DIANA; MOYANO GABRIEL

Huerta Grande

Workshop; Escuela Argentina de Biología y Matemática; 2016

We analyze the ecology stability of Rhizobium-legume symbiosis, using population dynamic models experimentally based. We include in the model two rhizobial strains differing in their ability to fix N$_2$ for the plant, and explore the influence of horizontal transfer of symbiotic genes, competition between fix+ and fix- strains for nodulation and nodule co-occupation by the two strains. We also explore the case of potential sanctions applied by the plant to ineffective rhizobia. Our model gives insights to explain the coexistence between fixing and non-fixing strains observed in the field.