Does simultaneous adoption of drought tolerant maize varieties and manure impact productivity and welfare outcomes? Evidence from rural Nigeria

Poor soil fertility and drought are among the major challenges limiting maize productivity in sub-Saharan Africa (SSA). Improved maize varieties and chemical fertilisers are widely promoted in SSA, however, unsustainable use of chemical fertilisers has huge implications for soil degradation. The synergies between improved maize varieties and sustainable land use management practices such as manure are poorly documented, despite the role of manure in enhancing long-term sustainability of soil organic matter which is critical for addressing poor soil fertility. Employing a nationally representative maize household survey in Nigeria, this study utilises multivalued inverse probability weighting (MIPWRA), entropy balancing and multinomial endogenous switching regression (MESR) model to determine the impacts of the adoption of combinations of drought-tolerant maize varieties (DTMVs) and manure on farm households’ productivity and welfare outcomes (per capita total expenditure and per capita food expenditure). The estimation results of the average treatment effects, when farm households’ observables and unobservables are corrected for, show that the highest pay-off on productivity and welfare outcomes is achieved when DTMVs and manure are jointly adopted. This study also finds that wealth indicators, access to loans, and access to extension services play a significant role in driving both individual and combinatory packages of DTMVs and manure. Overall, this study concludes that simultaneous adoption of DTMVs and manure can enhance agricultural productivity and welfare for rural farmers and significantly contribute to the achievement of sustainable agricultural practices among maize farm households