0000000000636293
AUTHOR
Karine Heulin-gotty
Genetic diversity for partner choice in a core collection of pea accessions inoculated by a mix of five Rhizobium leguminosarum bv. viciae genotypes
National audience
GRaSP project Genetics of Rhizobia Selection by Pea
Prod 2019-88aa; National audience; Because of their ability to fix nitrogen in symbiosis with soil bacteria, legumes such as peas have an important role to play in the development of a sustainable agriculture. However, in the field, biological nitrogen fixation (BNF) could be suboptimal as natural Rhizobium leguminosarum viciae (Rlv) populations are quantitatively and qualitatively heterogeneous, with strains varying in their competitiveness and efficiency of BNF [1,2]. There is a general agreement concerning the interest of Rlv inoculation for improving BNF and thus pea yield [3]. However, even when pea seeds are inoculated by efficient Rlv strains these can be outcompeted by indigenous rh…
The competitiveness to form nodules shapes the capacities of Rhizobium leguminosarum sv viciae communities to promote symbiosis with specific hosts
National audience; Cultivated fabeae legumes (pea, fababean, lentil) develop root nodules resulting from the symbiotic interaction with Rhizobium leguminosarum sv. viciae (Rlv). Individual Rlv bacteria are able to associate with various potential hosts, but in soil they are in mixture and they display a wide range of competitiveness to form nodules (CFN). Because in Rlv, CFN and capacity to fix nitrogen are genetically independent, CFN limits the effectiveness of inoculation strategies as efficient bacteria are often outcompeted by poorly efficient Rlv bacteria of the soil community. We developed a strategy to identify bacterial genes controlling CFN. A worldwide collection of 240 Rlv isola…
Genetic diversity of nodulated root structure in a very diverse pea collection
National audience; The root system is responsible for nitrogen (N) acquisition, which in legumes, combines mineral acquisition and symbiotic fixation in nodules. Despite these two complementary pathways, N nutrition may be a limiting factor of legumes yield because nodules are very sensitive to their local environment and N fixing legume root system is poorly developed which may limit soil exploration [1]. Pea establishes in root nodules a symbiotic association with Rhizobium leguminosarum sv viciae bacteria (Rlv) [2]. This study assessed the potential of naturally occurring genetic variability of nodulated root structure and functioning traits to improve yield pea performance. Two successi…