Sustainable Practices for Arid Climates: Evaluating Combined Mulches with Biostimulant in Combating Soil Salinity and Cowpea Cultivation

Abstract

Salinity and water security are significant challenges in arid climates, necessitating effective practices to enhance crop productivity in these stressful environments. To address this, a study was conducted during the summer seasons of 2022 and 2023 using a randomized, completely block setup with three replications. The research assessed the effects of different mulch materials, unmulched (bare soil), white plastic, rice straw, and sawdust, combined with biostimulant foliar applications (control, bulk chitosan at 250 mg/L, and two concentrations of chitosan nanoparticles at 125 mg/L and 62.5 mg/L) on physiochemical and biological properties of salt-affected soil, as well as on the growth and yield of cowpeas. The findings of this study indicate that different mulch materials exert distinct effects based on their type. For instance, white plastic mulch with chitosan nanoparticles at a concentration of 62.5 mg/L markedly decreased soil salinity (by 10.80% and 14.64%) and ESP (by 6.93% and 6.80%). In contrast, white plastic mulch paired with a control foliar application significantly increased the soil moisture content (by 23.93% and 27.63%) compared to un-mulched soil. The combination of organic mulches and biostimulant foliar treatments significantly enhanced soil health by increasing the pH, organic carbon, nutrient content, and beneficial bacteria while reducing the bulk density and suppressing harmful fungi. Biostimulant foliar treatments have a modest affected soil property. Additionally, this study highlights that integrating specific mulching materials with biostimulant foliar treatments can significantly improve cowpea’s vegetative growth, yield, and nutrient content. This suggests that combining mulches and biostimulants may provide a sustainable solution for enhancing cowpea production in saline environments.

Keywords

• chitosan
• cowpeas
• mulching materials
• nanoparticles
• salt-affected soils