Synergistic phytohormone crosstalk enhances nickel detoxification, antioxidant defense and yield in isabgol (Plantago ovata).
Mehmood H, Murtaza G, Ali S, Alwutayd KM, Alharbi HM
Summary
PubMedCombining four plant signaling compounds (caffeic, jasmonic, salicylic, and abscisic acids) dramatically improves isabgol plant growth and seed production even when grown in nickel-contaminated soil, while also reducing toxic nickel accumulation in the crop.
chevron_right Technical Details
Key Findings
Synergistic application of the four compounds increased root length by 21%, shoot length by 21%, root fresh weight by 97%, and shoot fresh weight by 45% in nickel-stressed plants
Antioxidant enzyme activities increased by 31-73% (including 73% increase in ascorbate peroxidase), providing enhanced defense against heavy metal stress
Seed yield increased 51.16% while nickel accumulation in seeds decreased 49.69%, demonstrating feasibility for food production in contaminated soils
Original Abstract
The synergistic effect of caffeic, jasmonic and salicylic acids and abscisic acid was highly effective in reducing the phytotoxic effect of Ni in isabgol plants by promoting growth, physiological processes and nutrient metabolism. This study was necessitated by the need to formulate an effective plan to make plants more tolerant to heavy metal-contaminated soil. The experiment was performed in a pot test using a completely randomized design with four replications. Nickel stress (100 mg/kg soil) significantly reduced root length (49.49%), shoot length (44.59%), root fresh weight (60.05%), shoot fresh weight (55.85%) and chlorophyll content (52.66%) compared to the unstressed control. The synergistic application of caffeic acid (1 mM), jasmonic acid (100 µM), salicylic acid (1 mM) and abscisic acid (50 µM) significantly mitigated these effects, increasing root length, shoot length by 21%1%, root fresh weight by 97%7% and shoot fresh weight by 59%9%, 21%1%, 97%7% and 45.31%, respectively, relative to the Ni-stressed control. This treatment also enhanced the activities of antioxidant enzymes, including superoxide dismutase (31.98%), peroxidase (46.24%), catalase (35.98%), ascorbate peroxidase (73.39%), glutathione peroxidase (62.94%) and glutathione reductase (64.76%), as well as non-enzymatic antioxidants such as ascorbic acid (48.57%), anthocyanins (64.40%), β-cyanin (27.83%), β-xanthin (42.13%), phenolic content (33.51%) and flavonoid content (38.70%). It also reduced Ni accumulation in roots, shoots and seeds by 33.72%, 36.31% and 49.69%, respectively, while improving the uptake of essential nutrients, such as Fe (30.66%), Mn (35.52%), Zn (32.98%) and N (14.99%). Photosynthetic efficiency, membrane stability and relative water content were also restored, leading to a 51.16% increase in seed yield. The synergistic interaction of these compounds enhances stress signaling, redox balance and metabolic regulation more effectively than their individual applications. Therefore, the combined exogenous application of caffeic acid, jasmonic acid, salicylic and abscisic acid is recommended as a sustainable strategy to improve Isabgol production in nickel-contaminated environments.
This connects to 10 other discoveries — 1 species, 4 topics, 5 related articles
Species Mentioned
Psyllium, or Isabgol or ispaghula, is the common name used for several members of the plant genus Plantago whose seeds are used commercially for the production of mucilage. Psyllium is mainly used as a dietary fiber to relieve symptoms of both constipation and mild diarrhea, and occasionally as a...
open_in_new Wikipedia