Effects of superabsorbent hydrogel on tomato crop growth and productivity under different water deficit levels

Abstract

Tomato (Solanum lycopersicum L.) is one of the most important horticultural crops worldwide, valued for both its nutritional and economic significance. However, its high sensitivity to water scarcity severely limits growth, reduces yield, and compromises fruit quality. This study aims to evaluate the effects of superabsorbent polymer (SAP) application on the growth and productivity of tomato plants subjected to different irrigation regimes. A greenhouse pot experiment was conducted using two factors i): three SAP levels (0.0wt%, 0.05wt%, and 0.1wt%) ii): four irrigation regimes corresponding to 100%, 70%, 50%, and 30% of pot capacity. The experimental setup followed a completely randomized block design comprising three blocks, with three replications for each treatment to ensure statistical reliability and minimize environmental variability. The findings reveal that SAP application enhances vegetative development by promoting stronger plant growth and greater leaf expansion, whereas drought stress significantly restricts these parameters. At the physiological level, SAP interacts with water stress to preserve chlorophyll content and osmotic stability, thereby sustaining photosynthetic activity and facilitating sugar accumulation under deficit conditions. Overall, the study demonstrates that SAP application improves water use efficiency and supports tomato growth and yield in water-limited environments, emphasizing its potential as an effective soil amendment to mitigate the adverse impacts of drought on horticultural crops