The yield-increasing effect and heterogeneity of scientific planting: an empirical analysis based on the ordered model

To explore the yield-increasing effect and internal transmission path of scientific cultivation practices on the per-mu yield of sweet potatoes, this study conducts an empirical analysis of the impact of scientific cultivation on sweet potato yield per unit area, based on a survey dataset of 682 sweet potato farmers across 11 prefecture-level cities in Jiangxi Province in 2024, and empirically tests the influence and mechanism of scientific cultivation on the per-mu yield of sweet potatoes from the mediating perspective of technology cognition and mechanization rate. The results show that: (1) Scientific cultivation exerts a significant yield-increasing effect on sweet potato per-mu yield. Different dimensions of scientific cultivation practices, including variety optimization, technology application, and training participation, all have a positive impact on sweet potato per-mu yield, among which the boosting effect of training participation is the most pronounced. (2) Heterogeneity analysis reveals that the yield-increasing effect of scientific cultivation on sweet potato per-mu yield varies substantially with planting scale and yield expansion intention, specifically, the effect is more prominent for large-scale farmers than for small-scale ones; and it is stronger for farmers with yield expansion intention than for those without such intention. (3) Mechanism analysis indicates that scientific cultivation can promote the increase of sweet potato per-mu yield by enhancing farmers' technology cognition level and improving the application rate of mechanization. In view of the above findings, this study puts forward quantifiable and implementable policy recommendations from four dimensions: strengthening the extension of scientific cultivation technologies, carrying out hierarchical and classified agricultural technical training, promoting the coordinated adaptation of mechanization and scientific cultivation, and improving government institutional guarantees, so as to drive the large-scale and standardized development of the sweet potato industry, enhance production efficiency, and provide strong support for safeguarding food security.