# Impact of Zeolites on Growth Dynamics of Medicago sativa and Lactuca sativa in Hydroponics

## TL;DR

Natural zeolite improves hydroponic plant growth by enhancing moisture and nutrient retention compared to commercial substrates.

## Contribution

Demonstrates natural zeolite's efficacy as a hydroponic substrate through growth and metabolic analysis of specific plant species.

## Key findings

- Zeolite has a significantly higher specific surface area (21.80 m2/g) than the control (0.49 m2/g), improving moisture and cation exchange.
- Zeolite promotes better root development and seedling viability in Medicago sativa compared to artificial substrates.
- GC–MS analysis shows zeolite induces metabolic changes in Lactuca sativa, including increased fatty acids and genotype-specific osmoregulation.

## Abstract

This study evaluates the effectiveness of natural zeolite (Shankhanai deposit, Kazakhstan) as a functional hydroponic substrate compared to a commercial foamed-glass control (GrowPlant). Using the Nutrient Film Technique (NFT), we assessed the growth and metabolic responses of Medicago sativa L. and three cultivars of Lactuca sativa L. Brunauer–Emmett–Teller (BET) analysis confirmed that zeolite (particle size 3.70 ± 1.20 mm) possesses a high specific surface area (21.80 m2/g), significantly exceeding the control (0.49 m2/g). This structure ensured superior moisture retention and cation exchange, even after a moderate decrease in surface area to 16.66 m2/g post-cultivation due to organic pore-filling. In M. sativa experiments, zeolite increased seedling viability and promoted a more branched root system compared to the artificial substrate. Gas chromatography–mass spectrometry (GC–MS) metabolic profiling of L. sativa revealed a significant substrate-driven reprogramming: zeolite increased the relative proportion of fatty acids and their derivatives (up to +51.27% in May King variety roots), suggesting membrane-protective adaptation. Genotype-specific responses were observed, with the Yeralash cultivar showing increased polyol synthesis (+2.93%) for osmoregulation. The results demonstrate that natural zeolite is an efficient, stable substrate for intensive hydroponics, optimizing root development and physiological stability through enhanced nutrient and water management.