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

Abstract

This paper uses a multinomial endogenous treatment effect model and data from a sample of 470 farming households to assess the impacts of adopting sustainable agricultural practices (SAPs) on farm yield and household incomes among smallholder maize farmers in Morogoro region. Results show that combination of improved maize and crop residual significantly increased maize yield by 46%, while intercropping with crop residual (65%), improved maize seeds with manure use (58%), and maize rotation with intercropping (57%). The model estimates indicate that individual elements of SAPs increased yield by crop residual (30%), crop rotation (38%), improved maize varieties (85%), intercropping (58%), and manure (43%) whereas, the application of bundled SAPs had significant impacts on the household income via the following combinations; maize-legume rotation and crop residual (50%), improved maize and crop residual (46%), improved maize and manure (70%), maize-legumes rotation and improved maize (46%), maize rotation and intercropping (68%), maize rotation, improved maize, crop residual, and intercropping (41%), and lastly improved maize, intercropping, manure, crop residual, and crop rotation (55%). 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 productivity and incomes, while simultaneously addressing issues related to the dis-adoption of SAPs, and climate change, by raising awareness and educating to farmers about the benefits of using SAPs and implementing mitigative measures for climate change. This includes providing financial incentives such as loans and subsidies, as well as conducting policy reforms to evaluate and adjust policies that currently favor the use of conventional practices in Tanzania.