Exogenous Applications of Naphthaleneacetic Acid and Indole-3-Acetic Acid on Selected Crops Under MgCl2 Stress

Exogenous Applications of NAA and IAA on Selected Crops Under MgCl2 Stress

Abstract

Salt stress in agricultural soils can induce significant stress detrimental to crops, the environment, and human health. This study evaluated the efficacy of topically administered phytohormones indole-3-acetic acid (IAA) and naphthalene acetic acid (NAA) in alleviating stress induced by magnesium chloride (MgCl₂) in Abelmoschus esculentus (A. esculentus) and Zea mays (Z. mays). In controlled laboratory (Petri plate) and field-pot environments, morphological, physiological, and biochemical responses were evaluated utilizing a Randomized Complete Block Design (RCBD) with three replications. Both low and high concentrations of MgCl₂ resulted in a significant reduction in biochemical and growth indicators, such as leaves number, area of leaf, and shoots and length of root. In A. esculentus and Z. mays, the combination of MgCl₂ with IAA and NAA significantly enhanced seedling growth. Biochemical investigations shows that the hormone-assisted (IAA and NAA) therapy revealed increased levels of carotenoids, proteins, carbohydrates, chlorophyll “a”, “b”, total chlorophyll and decline the proline contents in both crops compered to MgCl₂ stress. In conclusion, MgCl₂ resulted in significant adverse effects on both species; however, the foliar application of IAA and NAA mitigated stress-induced damage, whereas A. esculentus exhibited greater resistance compared to Z. mays.