# Impact of integrating zeolite and PGPR on restoring soil health and enhancing crop yields following the leaching process

## TL;DR

This study shows that combining zeolite and beneficial soil bacteria can improve soil health and crop yields after leaching salty soils.

## Contribution

The novel approach combines zeolite and PGPR to restore soil health and increase crop yields after leaching.

## Key findings

- Combined zeolite and PGPR treatment increased cation exchange capacity, nutrient availability, and microbial activity.
- Rice and wheat yields increased to 11.78 t/ha and 7.44 t/ha with the Z+PGPR treatment.
- Soil infiltration rate improved to 1.09 cm/h under the Z+PGPR treatment.

## Abstract

Soil leaching is a traditional approach for reclaiming saline soil; however, it often leads to nutrient loss that further weakens soil health. Therefore, this study examines the use of zeolite in combination with plant growth-promoting rhizobacteria (PGPR) as a sustainable approach to restore soil health and enhance rice and wheat yields following soil leaching. The study farm affected by salinity and sodicity is located near Kafr Basat, Dakahlia Governorate, Egypt, during the period from 2023 to 2024. A 10-week sequential leaching process (L1–L5) reduced electrical conductivity (EC) by approximately 45% and exchangeable sodium percentage (ESP) by 42% across the soil profile. However, leaching resulted in declines in soil nutrient contents and microbial activity. Four treatments: control, zeolite (Z), PGPR, and combined zeolite + PGPR (Z+PGPR), were applied using a randomized block design with three replicates. The Z+PGPR treatment significantly improved soil chemical and biological properties, including increases in cation exchange capacity (CEC) (up to 37.21 cmol kg−1), nitrogen, phosphorus, and potassium availability, as well as microbial biomass carbon (MBC), which increased from 4.04 to 4.37 mg/g soil. CO2 respiration increased by 62.3%, indicating enhanced microbial activity. Additionally, EC and ESP were further reduced, and infiltration rate improved to 1.09 cm h−1 under the Z+PGPR treatment. Correspondingly, rice and wheat yields increased to 11.78 t/ha and 7.44 t/ha, respectively. These results suggest that the combined application of zeolite with PGPR can enhance soil health and crop productivity following soil leaching. Nevertheless, long-term studies, multiple sites and economic assessments are needed to confirm the broader applicability and sustainability of this approach.