Reducing chemical fertilizer use to rice through integrated nutrient management in rice (Oryza sativa) groundnut (Arachis hypogaea) cropping systems

Chemical fertilizer is very expensive for most smallholder farmers in northeastern Thailand. Grain legumes can be grown in dry season to provide cash income and residues for green manure for succeeding crop. The current study was to evaluate the effect of groundnut stover incorporation to the soil integrated with chemical fertilizer on growth and yield of succeeding rice crop grown under rainfed conditions.

Groundnut planted in dry season by supplemental irrigation. At harvest time, groundnut stover were sampled to determine the dry weight and analysis for nutrients content, as well as calculated the amount of nutrients return to the soil. Incorporation of groundnut stover combined 50% dose of chemical fertilizer was compared with 100% dose of chemical fertilizer treatment using by the farmer at two locations. Growth and yield of succeeding rice crop were evaluated at harvest.

Incorporation of groundnut stover combined 50% dose of chemical fertilizer had similar grain yields of rice to that of using 100% dose of chemical fertilizer alone as use by the farmers. This indicates that groundnut grown in dry season provided not only cash income, but also for green manure to the succeeding rice crop.