Aspirin Foliar Spray-Induced Changes in Light Energy Use Efficiency, Chloroplast Ultrastructure, and ROS Generation...

Area of Science:

• Plant Physiology
• Biochemistry
• Agricultural Science

Background:

• Aspirin (Asp) is a widely used drug with known anti-inflammatory properties.
• Salicylic acid (SA) shares physiological similarities with Asp and is known to benefit plant health.
• The potential of Asp as a plant biostimulant for improving photosynthetic function is underexplored.

Purpose of the Study:

• To investigate the effects of foliar Aspirin (Asp) application on tomato plant photosynthetic efficiency.
• To compare the beneficial effects of Asp on photosynthesis with those of salicylic acid (SA).
• To assess Asp's impact on reactive oxygen species (ROS) generation and chloroplast structure.

Main Methods:

• Foliar spray of Aspirin (Asp) was applied to tomato plants.
• Photosystem II (PSII) efficiency was assessed.
• Reactive oxygen species (ROS) generation was measured.
• Chloroplast ultrastructure was examined.

Main Results:

• Asp increased tomato leaf water content and provided antioxidant protection, maintaining a more oxidized redox state of plastoquinone (PQ).
• This resulted in enhanced PSII photochemistry (ΦPSII) and reduced ROS formation, including singlet oxygen (¹O₂).
• Asp decreased stomatal opening, reduced transpiration, and mitigated the need for photorespiration, indicating a photoprotective effect.

Conclusions:

• Aspirin (Asp) acts as an osmoregulator and antioxidant in tomato plants.
• Foliar Asp application enhances photosynthetic function and offers photoprotection, particularly under high light conditions.
• Asp demonstrates comparable beneficial effects to salicylic acid (SA), functioning as a biostimulant to potentially improve crop yield.