Ex-ante Economic Impact Assessment of Green manure Technology in Maize Production Systems in Tanzania

Abstract

In maize-based farming systems, intercropping of maize with green manure have been increasingly been one of the strategies to revive the declining maize production caused by increasing pests’ infestations and low soil fertility. This study analyzed the potential impacts of adoption of green manure technology on yield, cost, and profitability of maize production in the Eastern Zone of Tanzania. To assess the income and costs effects of maize production using green manure, a farm level budget was constructed from primary and secondary sets of data and information using a with-and-without framework of analysis. A partial budget was constructed to determine the incremental benefits from costs of adopting the green manure technology in managing noxious weeds such as Striga. Results showed that the adoption of green manure technology has a high potential to increase marketable yield, reduce costs and increase net profits. The partial budget analysis showed that green manure would give a net incremental benefit of Tsh. 478 654/acre compared to the chemical fertilizers used by farmers. These additional benefits were realized from increased marketable yields and savings from reduced chemical fertilizers and labour costs. Future research should strive to further develop and strategize dissemination channels to reach more of the smallholder population to increase their knowledge base on the alternative values of green manures.

Keywords: Green manure, ex-ante impact assessment, investment in technology, partial budgeting