Publications des agents du Cirad

Cirad

Nodulation of cowpea vigna unguiculata (var. Cylindrica) within agro ecological systems in northern vietnam ¿ needs for developing commercial rhizobial inoculants

Herviault T., Nguyen T.T., Nguyen H.T.T., Le Bui V., Otieno M., Couillerot O., Le Thuy Hang, Nguyen T.A., Lesueur D.. 2018. Narbonne : INRA, 1 p.. Journées Recherche-Industrie Management des ressources microbiennes. 2, 2018-05-29/2018-05-31, Narbonne (France).

With Myanmar, Vietnam is one of the biggest producers of grain legume in South East Asia. Unfortunately, farmers don't know anything about rhizobial inoculants and keep applying high rates (sometime more than 1 tonnes of NPK per ha) of mineral fertilizers for growing legumes and other associated crops. In Northern Vietnam, the soil erosion issue is very important because basically there are ills with almost no vegetation and when it rains, the water runs off and the soil become highly degraded. The promotion of the intercropping system is relevant because the legume release part of the atmospheric nitrogen they fixed in symbiosis with rhizobia and it contributes to maintain yields to a certain level. However, the absence of rhizobial inoculants and the systematic utilization of mineral fertilizers reduce the potential of the biological nitrogen fixation. Our study was aiming to point out this in 2 districts of the Yen Bai province in Norther Vietnam where the local authorities try to promote as much as they can agro-ecological practices such as intercropping. Basically, our results showed the nodulation of cowpea intercropped with maize or cassava remained limited whatever the soil characteristics and the landscape. There are native rhizobial strains available within the soils, but their numbers need to be increased, their genetic diversity has to be assessed and their effectiveness has to be measured. It becomes urgent to move on with new initiatives involving the private sector aiming to elaborate effective commercial rhizobial inoculants for grain legumes for Vietnam but also in the whole South East Asia to sustain legume and crop production through an environmental-friendly management. This is definitively the way forward and the market exists because of the huge demand, it is matter to make the inoculants available on the markets.

Documents associés

Communication de congrès

Agents Cirad, auteurs de cette publication :