Methionine Promotes the Growth and Yield of Wheat under Water Deficit Conditions by Regulating the Antioxidant Enzymes, Reactive Oxygen Species, and Ions

Abstract

The individual application of pure and active compounds such as methionine may help to address water scarcity issues without compromising the yield of wheat. As organic plant growth stimulants, amino acids are popularly used to promote the productivity of crops. However, the influence of the exogenous application of methionine in wheat remains elusive. The present investigation was planned in order to understand the impact of methionine in wheat under drought stress. Two wheat genotypes were allowed to grow with 100% field capacity (FC) up to the three-leaf stage. Twenty-five-day-old seedlings of two wheat genotypes, Galaxy-13 and Johar-16, were subjected to 40% FC, denoted as water deficit-stress (D), along with 100% FC, called control (C), with and without L-methionine (Met; 4 mM) foliar treatment. Water deficit significantly reduced shoot length, shoot fresh and dry weights, seed yield, photosynthetic, gas exchange attributes except for transpiration rate (E), and shoot mineral ions (potassium, calcium, and phosphorus) in both genotypes. A significant increase was recorded in superoxide dismutase (SOD), catalase (CAT), hydrogen peroxide (H2O2), malondialdehyde (MDA), and sodium ions (Na+) due to water deficiency. However, foliar application of Met substantially improved the studied growth, photosynthetic, and gas exchange attributes with water deficit conditions in both genotypes. The activities of SOD, POD, and CAT were further enhanced under stress with Met application. Met improved potassium (K), calcium (Ca2+), and phosphorus (P) content. In a nutshell, the foliar application of Met effectively amended water deficit stress tolerance by reducing MDA and H2O2 content under water deficit conditions in wheat plants. Thus, we are able to deduce a positive association between Met-induced improved growth attributes and drought tolerance.

B. subtilisCNBG‐PGPR‐1 induces methionine to regulate ethylene pathway and ROS scavenging for improving salt tolerance of tomato

“…Notably, the contents of H 2 O 2 and MDA significantly decreased after CNBG-PGPR-1 inoculation (Figure 8a,b). In general, plants nee tod produce antioxidant defense systems, such as superoxide dismutase (SOD), catalase (CAT), POD, and reduced glutathione (GSH) to inhibit oxidative damage by scavenging excess ROS (Mart ınez et al, 2017;Oliveira et al, 2023;Zhu et al, 2023). In this study, we found that ROS scavenger-encoding genes were induced by CNBG-PGPR-1, most of which were related to GSH metabolism and POD-coding genes (Figure 8c).…”

“…Exogenous L‐methionine also largely mimicked the GSH/GSSH ratio and POD activity in plants under salt stress (Figure S7). In fact, apart from serving as a precursor to ethylene synthesis, methionine is closely associated with reducing ROS production to protect plant cells from oxidative damage under abiotic stress (Maqsood et al., 2022). There is a certain relationship between cysteine and GSH metabolism, while cysteine and methionine convert to each other in the metabolic pathway, which explains the possible reason for the increase in GSH content after CNBG‐PGPR‐1 inoculation (Freeman et al., 2004).…”

“…Three days after the first inoculation with CNBG‐PGPR‐1, tomato seedlings were root irrigated and foliar applied with 10 μ m AVG and 4 m m AgNO 3 (Borbély et al., 2020; Singh et al., 2023) followed by 70 ml of 200 m m NaCl. To verify the effects of the ethylene synthesis precursor methionine on salt tolerance in tomato, 4 mM L‐methionine was exogenously applied under salt conditions (Maqsood et al., 2022) using the same method as above. After 2 weeks of salt stress, five tomato seedlings were randomly selected under each treatment, and morphological traits, that is, plant height (cm), root length (cm), plant FW/DW (g), and root FW/DW (g), were measured.…”

“…On the other hand, when plants are subjected to environmental stress, such as drought, salt stress, and cold stress, which often trigger the production of ROS (reactive oxygen species), severely limiting plant growth and development (Cui et al, 2022). Methionine can participate in the regulation of the antioxidant defense system, helping plants resist oxidative damage (Mart ınez et al, 2017;Oliveira et al, 2023;Zhu et al, 2023). Thus, it is apparent that methionine serves not only as an essential amino acid but also as a vital biological regulator in plants.…”

TiO2 nanoparticles alleviates the effects of drought stress in tomato seedlings

“…Up-regulation of 5-methyltetrahydropteroyltri glutamatehomocysteine S-methyltransferase and geranylgeranyl diphosphate reductase proteins with TiO 2 -treatment may enhance the methionine, tocopherol and chlorophyll metabolisms for tomato plants to cope with drought stress. Maqsood et al (2022) showed that exogenous methionine application alleviated drought related inhibition via reducing reactive oxygen species content and enhancing antioxidant capacity. Similar results were also reported for tocopherol by Ma et al (2020).…”