Nyangena, Wilfred and Maurice Juma Ogada. 2014. “Impact of Improved Farm Technologies on Yields The Case of Improved Maize Varieties and Inorganic Fertilizer in Kenya.” EfD Discussion Paper Series EfD DP 14-02.
This study investigates the impact of package adoption of inorganic fertilizers and improved maize seed varieties on yield among smallholder households in Kenya. We used a quasi-experimental difference-in-differences approach combined with propensity score matching to control for both time-invariant and unobservable household heterogeneity.
Our findings show that inorganic fertilizers and improved maize varieties significantly increase maize yields when adopted as a package, rather than as individual elements. The impact is greater at the lower end of the yield distribution than at the upper end. A positive effect of partial adoption is experienced only in the lower quartile of yield distribution. The policy implication is that complementary agricultural technologies should be promoted as a package, and should target households and areas experiencing low yields.