Economic impact of adopting bundled SAPs on crop yields and household incomes among smallholder maize farmers in Morogoro region, Tanzania

This paper uses a multinomial endogenous switching regression and data from a sample of 470 farming households to assess the impacts of adopting sustainable agricultural practices (SAPs) on farm yields and household incomes among smallholder maize farmers in Morogoro region. Results show that the following combinations had significant impacts on the maize yields: improved maize varieties with crop residual by (46%), maize legume rotation with crop residual (49%), intercropping with crop residual (65%), improved maize varieties with manure use (58%), maize rotation with intercropping (57%), maize–legume rotation, intercropping, improved maize varieties with manure use (80%), intercropping with improved maize varieties (55%), improved maize varieties,intercropping,manure, crop residual and crop rotation (74%). Moreover, the model estimates indicate that individual elements of SAPs significantly increased yield by the following percents; crop residual (30%), improved maize varieties (85%), intercropping (58%), and manure (43%), whereas, the application of bundled SAPs had significant impacts on household income via the following combinations; maize-legume rotation with crop residual (50%), improved maize varieties with crop residual (46%), improved maize varieties with manure (70%), maize-legumes rotation with improved maize varieties (46%), maize rotation and intercropping (68%), maize rotation, improved maize varieties, crop residual, with intercropping (41%), intercropping and improve maize (57%), improved maize varieties , intercropping, manure, crop residual, and crop rotation (55%). Individual elements of SAPs significantly increased income by the following percentages; crop rotation (48%), improved maize varieties (65%), intercropping (48%), and manure (43%) The study recommends actors involved in the design, promotion and dissemination of SAPs to find a suitable mix or combination of these practices that will enhance maize yields and incomes, while simultaneously addressing issues related to the dis-adoption of SAPs, and interventions to climate change, by raising awareness and educating farmers about the benefits of using SAPs and implementing mitigative measures for climate change. This includes providing of financial incentives such as loans and subsidies, as well as conducting policy reforms to evaluate and adjust policies that favor the use of conventional practices in Tanzania