Less is more? The adoption and economic impact of agrochemical control on grain production in the North China Plain

The intensive and inefficient use of agrochemicals in developing countries has raised major concerns for both agricultural sustainability and environmental quality. This study examines the economic implications of farmers’ agrochemical control decisions—specifically the management of fertilizers and pesticides—in China's input-intensive maize production system. Using primary survey data from 549 maize-producing households in the North China Plain, we estimate an endogenous switching regression (ESR) model to account for self-selection bias arising from observable and unobservable factors. The results indicate that reducing fertilizer use within reasonable bounds does not reduce maize yield and can significantly increase farm income, while more targeted pesticide management raises both yield and income. Furthermore, the coordinated control of fertilizer and pesticide use generates combined economic benefits, highlighting potential synergies in integrated input management. Robustness checks using propensity score matching confirm the stability of these results. By demonstrating that moderate reductions in agrochemical use can enhance profitability, this study provides empirical evidence supporting the flat payoff function framework and contributes to the literature on sustainable intensification. It underscores the importance of supporting smallholders through information, extension, and incentive mechanisms that promote efficient and environmentally responsible input use.