Open Access

ARTICLE

Role of foliar spray of plant growth regulators in improving photosynthetic pigments and metabolites in Plantago ovata (Psyllium) under salt stress–A field appraisal

ABDUL SAMAD¹, KANVAL SHAUKAT^1,*, MAHMOOD-UR-REHMAN ANSARI², MEREEN NIZAR¹, NOREEN ZAHRA³, AMBREEN NAZ⁴, HAFIZ MUHAMMAD WALEED IQBAL⁵, ALI RAZA⁶, VLADAN PESIC⁷, IVICA DJALOVIC⁸

1 Department of Botany, University of Balochistan, Quetta, 08770, Pakistan
2 Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, 38000, Pakistan
3 Department of Botany, University of Agriculture, Faisalabad, 38040, Pakistan
4 Department of Food Science and Technology, Muhammad Nawaz Shareef University of Agriculture, Multan, 66000, Pakistan
5 Department of Agronomy, Muhammad Nawaz Shareef, University of Agriculture, Multan, 66000, Pakistan
6 College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
7 Department of Genetics and Plant Breeding, Faculty of Agriculture, University of Belgrade, Belgrade, 11000, Serbia
8 Institute of Field and Vegetable Crops, National Institute of the Republic of Serbia, Maxim Gorki 30, Novi Sad, 21000, Serbia

* Corresponding Author: KANVAL SHAUKAT. Email:

(This article belongs to the Special Issue: Physiology and Molecular Biology of Plant Stress Tolerance)

BIOCELL 2023, 47(3), 523-532. https://doi.org/10.32604/biocell.2023.023704

Received 10 May 2022; Accepted 13 September 2022; Issue published 03 January 2023

Abstract

Salinity is one of the major abiotic factors that limit the growth and productivity of plants. Foliar application of plant growth regulators (PGRs) may help plants ameliorate the negative impacts of salinity. Thus, a field experiment was conducted at the Botanical Garden University of Balochistan, Quetta, to explore the potential role of PGRs, i.e., moringa leaf extract (MLE; 10%), proline (PRO; 1 µM), salicylic acid (SA; 250 µM), and thiourea (TU; 10 mM) in ameliorating the impacts of salinity (120 mM) on Plantago ovata, an important medicinal plant. Salinity hampered plant photosynthetic pigments and metabolites but elevated oxidative parameters. However, foliar application of PGRs enhanced photosynthetic pigments, including Chl b (21.11%), carotenoids (57.87%) except Chl a, activated the defense mechanisms by restoring and enhancing the metabolites, i.e., soluble sugars (49.68%), soluble phenolics (33.34%), and proline (31.47%), significantly under salinity stress. Furthermore, foliar supplementation of PGRs under salt stress led to a decrease of about 43.02% and 43.27% in hydrogen peroxide and malondialdehyde content, respectively. Thus, PGRs can be recommended for improved photosynthetic efficiency and metabolite content that can help to get better yield under salt stress, with the best and most effective treatments being those of PRO and MLE to predominately ameliorate the harsh impacts of salinity.

---

Keywords

---