Publications des scientifiques de l'IRD

Herrmann L., Chotte Jean-Luc, Thuita M., Lesueur D. (2014). Effects of cropping systems, maize residues application and N fertilization on promiscuous soybean yields and diversity of native rhizobia in Central Kenya. Pedobiologia, 57 (2), p. 75-85. ISSN 0031-4056.

Titre du document
Effects of cropping systems, maize residues application and N fertilization on promiscuous soybean yields and diversity of native rhizobia in Central Kenya
Année de publication
2014
Type de document
Article référencé dans le Web of Science WOS:000335107800003
Auteurs
Herrmann L., Chotte Jean-Luc, Thuita M., Lesueur D.
Source
Pedobiologia, 2014, 57 (2), p. 75-85 ISSN 0031-4056
Agriculture intensification has resulted in severe soil nutrient depletion in Africa. Alternative agricultural practices have been promoted to reduce the use of expensive mineral fertilizers and to restore and sustain soil fertility. The use of mineral fertilizer combined with organic inputs (such as crop residues) and different cropping systems (cereal-legume association or rotation) have been particularly promising. Impacts of these agricultural practices on soil communities have been widely studied, yet little is known on the effect on more specific groups such as rhizobia. A field trial was set up in Chuka (Kenya) to assess the impact of different cropping systems (maize and soybean in intercropping, rotation or monocropping) combined with N fertilization and residues application on the genetic diversity of promiscuous soybean rhizobia during two seasons. Soybean yields were severely reduced by moisture stress and the association with maize compared to mono-legume and rotation systems. Nodulation was generally low but was positively affected by residues application. Diversity of native rhizobia was very low (Shannon indices H' <0.8) across the experiment and was not affected by the treatments. Only 5 IGS profiles were obtained after RFLP analysis and all isolated rhizobia were identified as Bradyrhizobium elkanii. The distribution of the different IGS groups within the experiment was more affected by season and residues application than by cropping system and nitrogen fertilizer application. These results suggest a limited population and a low diversity of indigenous rhizobia, and emphasize the need of alternative managements to increase and sustain soybean yields in Central Kenya.
Plan de classement
Pédologie [068] ; Sciences du monde végétal [076] ; Biotechnologies [084]
Description Géographique
KENYA
Localisation
Fonds IRD [F B010061973]
Identifiant IRD
fdi:010061973
Contact