Plastic Mulch as a Sustainable Yield-Boosting Strategy for Fresh Corn Production in the Andean Region of Ecuador

The use of plastic mulch is a promising agronomic technique for enhancing crop performance under challenging environmental conditions. Mulching is commonly employed in horticultural crops, providing benefits such as increased yields, effective weed control, soil moisture conservation, and elevated soil temperature. However, its advantages for Andean crops have been insufficiently studied. This research evaluated the impact of plastic mulch on fresh corn yield across 19 locations in the Sierra (highlands) of Ecuador over two production cycles (2022–2023 and 2023–2024). Results indicated that plastic mulching significantly increased yields compared to conventional planting methods, with mean increases of 55.06% in the first cycle and 66.27% in the second cycle. A meta-analysis of 28 field trials confirmed a strong and statistically significant overall yield effect of the mulch (Standardized mean difference = 1.62; p < 0.0001). Further analysis revealed that combining plastic mulch with improved maize varieties resulted in significantly higher yields (14.78 ± 0.56 t·ha−1) compared to local varieties (10.00 ± 0.74 t·ha−1), indicating a synergistic effect. Notably, reutilized plastic mulch performed comparably to new mulch, showing no statistically significant difference in yield, suggesting agronomic viability beyond one cycle. The profitability analysis demonstrated that reutilized plastic mulch provided the highest economic return (benefit/cost ratio of 1.76) and posed less economic risk compared to conventional planting. These findings indicate that plastic mulching can be both a profitable and environmentally responsible practice. In contrast, conventional management was associated with greater risk and occasional financial loss.