Exogenous application of salicylic acid induces salinity tolerance in eggplant seedlings

Abstract

Under salt stress conditions, plant growth is reduced due to osmotic, nutritional and oxidative imbalance. However, salicylic acid acts in the mitigation of this abiotic stress by promoting an increase in growth, photosynthesis, nitrogen metabolism, synthesis of osmoregulators and antioxidant enzymes. In this context, the objective was to evaluate the effect of salicylic acid doses on the growth and physiological changes of eggplant seedlings under salt stress. The experiment was conducted in a greenhouse, where the treatments were distributed in randomized blocks using a central composite matrix Box with five levels of electrical conductivity of irrigation water (CEw) (0.50; 1.08; 2.50; 3.92 and 4.50 dS m-1), associated with five doses of salicylic acid (SA) (0.00; 0.22; 0.75; 1.28 and 1.50 mM), with four repetitions and each plot composed of three plants. At 40 days after sowing, plant height, stem diameter, number of leaves, leaf area, electrolyte leakage, relative water content, and total dry mass were determined. ECw and SA application influenced the growth and physiological changes of eggplant seedlings. Increasing the ECw reduced growth in the absence of SA. Membrane damage with the use of SA remained stable up to 3.9 dS m-1 of ECw. The relative water content independent of the CEw increased with 1.0 mM of SA. The use of SA at the concentration of 1.0 mM mitigated the deleterious effect of salinity on seedling growth up to 2.50 dS m-1 of ECw.

Evaluation of Salicylic Acid Effects on Growth, Biochemical, Yield, and Anatomical Characteristics of Eggplant (Solanum melongena L.) Plants under Salt Stress Conditions

“…Hence, these results might be connected to the alleviation effects of SA against harmful S effects by inducing growth hormones like IAA and cytokinins, which in turn reduce the uptake of toxic ions. This also maintains the integrity of the cell membrane, leading to improvements in cell division and plant growth in general [65]. In addition, the increase in CO 2 assimilation and photosynthetic rate increased mineral uptake in stressed plants [66].…”

“…Also, the enhancing effects of SA on total chlorophyll content may be attributed to its stimulatory effects on Rubisco activity [68]. The efficiency of exogenous SA application also relies on several factors, including the plant species, stage of development, method of application, and the applied concentration of SA [65].…”

Salt stress and organic fertilization on the growth and biochemical metabolism of Hylocereus costaricensis (red pitaya) seedlings

“…By reducing the rate of shoot production, plants consequently reduce their transpiration rate, decreasing water loss, which can ensure a higher survival rate (Fariduddin et al, 2012). With this, the plant ends up also reducing its photosynthetic capacity, since its area of light absorption is compromised, leading to decrease in size as well, as noted with Passiflora edulis (Mesquita et al, 2012), Capsicum annuum (Santos et al, 2019) and Solanum melongena (Sousa et al, 2022).…”

Hydrogen peroxide in attenuation of salt stress effects on physiological indicators and growth of soursop

“…The excess of salts in the irrigation water promotes the reduction of plant growth, because, while absorbing water, plants simultaneously absorb Na + and Clions, which cause damage to membranes, inactivation of biochemical pathways, consumption of reserves, and alterations in osmotic and ionic homeostase (Sá et al, 2022;Sousa et al, 2024). Salt stress also causes structural changes in photosynthetic pigments, compromising the excitation energy efficiency of the light-harvesting antenna and causing damage to photosystem II reaction centers (Tatagiba et al, 2014), affecting leaf turgor potential and inducing membrane damage.…”