The Influence of Salicylic Acid Treatment on Photosynthetic Pigments, Bioactive Compounds and Antioxidant Capacity in Drought-Stressed Petunia grandiflora

Abstract

Drought is widely recognized as the most severe environmental danger to horticulture in almost all regions across the globe. The objective of this study was to determine if applying a foliar treatment of salicylic acid (SA) at 400 ppm could mitigate the negative effects of drought on Petunia grandiflora. Four experimental variants were implemented for this purpose, with regular watering or moderate drought conditions. These variants were observed for duration of 14 days. The level of photosynthetic pigments was markedly greater in the samples exposed to drought but treated with foliar SA, in comparison to the samples exposed to drought without any treatment (128.28±8.78 and 38.01±1.15 µg/g total chlorophyll (a+b), respectively). The total polyphenol content and antioxidant capacity of both the leaves and flowers of Petunia were assessed. The polyphenols content was significantly reduced by drought. However, following the application of SA, anthocyanin levels increased in comparison to the sample that had been subjected to drought.The results demonstrate that applying SA to the leaves mitigates the adverse impacts of drought, providing a solution to the issue of water scarcity in ornamental plants, particularly Petunia grandiflora.