Thiamine-induced nitric oxide improves tolerance to boron toxicity in pepper plants by enhancing antioxidants

Abstract

The role of thiamine (THI)-induced nitric oxide (NO) synthesis in the improvement of tolerance to boron (B) toxicity in pepper (Capsicum annuum L.) was studied. A solution of THI (50 or 100 mg L -1 ) was sprayed to the foliage of pepper plants exposed to high B regime (2.0 mM H 3 BO 3 ) once a week for 4 weeks. A scavenger of NO (0.1 mM), cPTIO, along with THI was sprayed once a week to ascertain whether or not endogenous NO played a role in the alleviation of B stress in pepper plants by THI. There were significant reductions in plant dry weight, PSII quantum efficiency (F v /F m ), total chlorophyll, leaf calcium (Ca 2+ ) and potassium (K + ) contents as well as leaf water potential by 47.57%, 28.78%, 34.42%, 45.45%, 55.53%, and 471.4%, respectively, but there was a significant increase in the leaf proline, ascorbate (AsA), glutathione (GSH), hydrogen peroxide, malondialdehyde, electron leakage, B levels and NO by 2.6-, 2.3-, 1.9, 3.7-, 5.6-, 2.2-, 3.6-, and 3.0-fold, respectively in B-stressed plants. Both treatments of THI mitigated B-induced oxidative damage and led to a further increase in NO synthesis. The positive effect of THI on plants grown under B stress was fully eliminated by the cPTIO application by lowering leaf NO content. These findings exhibit that NO may function as a downstream signal in THI-induced tolerance to B toxicity in pepper plants by reversing oxidative stress, enhancing the antioxidant defense mechanism and sustaining mineral nutrient homeostasis. Thus, NO and THI both contributed to improved B toxicity tolerance in pepper plants.

Enhancing crop resilience through thiamine: implications for sustainable agriculture in drought-stressed radish

“…Similar findings were also observed in the current study that application of thiamine improved the antioxidant potential of the radish varieties (Atif and Perveen, 2023). As a result, thiamine supplementation contributes significantly to improving the antioxidant attributes of radish plants, making them better equipped to withstand the adverse effects of drought stress and promoting healthier growth and productivity (Kaya et al, 2020).…”

“…The imbalance in ion concentrations can disrupt several physiological processes, including enzyme activities and membrane functions (Ahmad et al, 2022). Consequently, this disruption may impair nutrient transport, protein synthesis, and overall plant metabolism, leading to reduced growth, wilted appearance, and decreased productivity of radish plants under drought stress (Kaya et al, 2020). Thiamine's involvement in various metabolic pathways can also aid in the efficient utilization of available ions, ensuring optimal nutrient absorption and utilization by the plant (Jabeen et al, 2022).…”

Morph-physiological and biochemical properties effects of exogenous nitric oxide applications on spinach under flooding stress conditions

“…It has been reported by many researchers that increasing extreme climate events negatively affect both soil quality and plant productivity (Rockström et al, 2017;Godoy et al, 2021;Sachdev et al, 2021). For this reason, researchers have focused on practices that reduce the yield and quality losses of plants under abiotic stress situations (Chernyshuk et al, 2020;Kaya et al, 2020).…”