Cowpea forms a symbiosis with soil bacteria of the genus Bradyrhizobium which leads to the fixation of atmospheric nitrogen. This nitrogen input primarily benefits the legume, but can also benefit associated crops in space (mixed farming) and over time (rotations).
These cropping systems associating cowpeas and dry cereals (millet, sorghum) allow productive and economical agriculture in inputs well adapted to the needs of family farming in the area. However, cowpeas are subject to strong abiotic constraints as well as ” to a fluctuation in their capacities for symbiotic associations, leading to low and unstable yields.
The genetic improvement of plant / bacterium associations and the reasoned inoculation of cultures with selected bacteria would optimize the symbiotic association. The objective of this project is to enhance the diversity of the two symbiotic partners (plant including wild relatives and bacteria) in order to identify effective associations for symbiotic fixation and adapted to water stress.
We will screen in optimal and limiting water condition a core collection of cowpea co-inoculated with a core-collection of bradyrhizobia (mixed) in the fields (over 2 years). We will identify the most effective associations by metabarcoding approaches.
We will select strains with high potential for inoculation and will carry out multi-local tests on the most promising symbiotic couples in association with farmer associations. This work will allow the selection of efficient cowpea varieties adapted to different pedoclimatic contexts and native strains for reasoned inoculation.
Teams involved: LCM, CERAAS, ENSAT, LSTM, DIADE
Theses: Seynabou DIOP (2016-2019)
