Effect of Growth Regulators and Nano Materials to Cope with Salinity on Anatomical Characteristics of Pea Plant

Abstract

Abiotic stresses, particularly salinity, severely hinder crop productivity by disrupting physiological processes and reducing yields. Pea (Pisum sativum L.), a vital crop, is highly sensitive to salinity, making it crucial to explore strategies that enhance its tolerance to such stresses.  This study investigates the effects of Ascorbic Acid (AsA), 5-Aminolevulinic Acid (ALA), and Nano-Selenium (N-Se) on the anatomical characteristics of pea  plants subjected to severe salinity stress (120 mM NaCl). Transverse sections of the fourth internode and leaf blade were analyzed, focusing on stem and leaf structure. The results showed that foliar application of AsA (100 ppm) significantly improved anatomical traits, such as stem diameter, cortex thickness, and vascular bundle dimensions, compared to the control and other treatments. ALA (50 ppm) also improved anatomical features, albeit to a lesser extent, while N-Se (20 ppm) exhibited the lowest enhancement. Leaf tissue analysis revealed that AsA improved leaflet structure, increasing epidermis thickness and vascular bundle dimensions under salinity stress. The application of AsA, ALA, and N-Se mitigated the negative effects of salinity, likely due to their roles in enhancing stress tolerance, reducing oxidative damage, and improving nutrient uptake. This study highlights the potential of these bio-stimulants to improve the anatomical resilience of pea plants under salinity stress, contributing to better crop performance in saline environments.