Short- and long-distance control of root development by LjHAR1 during the juvenile stage of Lotus japonicus.
The autoregulation of nodulation (AON) is a universal mechanism to legumes to control the extent of nodulation via a systemic circuit and if genetically altered, as in the Lotus japonicus har1-1 mutant, leads to hypernodulation and aberrant root development. Increased nodulation of har1-1 is associated with pleiotropic effects both in the absence and presence of the symbiosis. We used two different grafting techniques to investigate the control of the non-symbiotic retarded root growth phenotype of har1-1, and demonstrate that altered root growth in the non-symbiotic condition is controlled by the genotype of both the shoot and the root. Based on these results and on the Gresshoff and Delves [Plant genetic approaches to symbiotic nodulation and nitrogen fixation in legumes. Plant Gene Res 1986;3:159-206] AON model, we propose an advanced working model for control of root development by LjHAR1.
Buzas
Diana Mihaela
DM
ARC Centre Of Excellence For Integrative Legume Research, The University of Queensland, St Lucia, Queensland, Australia.
Gresshoff
Peter Michael
PM