Salinity is a ubiquitous stressor, depleting osmotic potential and affecting the tomato seedlings’ development and productivity. Considering this critical concern, we explored the salinity response in tomato seedlings by evaluating them under progressive salt stress duration (0, 3, 6, and 12 days). Intriguingly, besides the adverse effect of salt stress on tomato growth the findings exhibited a significant role of tomato antioxidative system, RBOH genes, ABA biosynthesis, and signaling transcription factor for establishing tolerance to salinity stress. For instance, the activities of enzymatic and non-enzymatic antioxidants continued to incline positively with the increased levels of reactive oxygen species (O₂^•−, H₂O₂), MDA, and cellular damage, suggesting the scavenging capacity of tomato seedlings against salt stress. Notably, the RBOH transcription factors activated the hydrogen peroxide-mediated signalling pathway that induced the detoxification mechanisms in tomato seedlings. Consequently, the increased gene expression of antioxidant enzymes and the corresponding ratio of non-enzymatic antioxidants AsA-GSH suggested the modulation of antioxidants to survive the salt-induced oxidative stress. In addition, the endogenous ABA level was enhanced under salinity stress, indicating higher ABA biosynthesis and signalling gene expression. Subsequently, the upregulated transcript abundance of ABA biosynthesis and signalling-related genes suggested the ABA-mediated capacity of tomato seedlings to regulate homeostasis under salt stress. The current findings have revealed fascinating responses of the tomato to survive the salt stress periods, in order to improve the abiotic stress tolerance in tomato.

Salicylic acid (SA) is considered to play an important role in plant responses to environmental stresses. However, the detailed protective mechanisms in photosynthesis are still unclear. We therefore explored the protective roles of SA in photosystem II (PSII) in Arabidopsis thaliana under high light. The results demonstrated that 3 h of high light exposure resulted in a decline in photochemical efficiency and the dissipation of excess excitation energy. However, SA application significantly improved the photosynthetic capacity and the dissipation of excitation energy under high light. Western blot analysis revealed that SA application alleviated the decrease in the levels of D1 and D2 protein and increased the amount of Lhcb5 and PsbS protein under high light. Results from photoinhibition highlighted that SA application could accelerate the repair of D1 protein. Furthermore, the phosphorylated levels of D1 and D2 proteins were significantly increased under high light in the presence of SA. In addition, we found that SA application significantly alleviated the disassembly of PSII-LHCII super complexes and LHCII under high light for 3 h. Overall, our findings demonstrated that SA may efficiently alleviate photoinhibition and improve photoprotection by dissipating excess excitation energy, enhancing the phosphorylation of PSII reaction center proteins, and preventing the disassembly of PSII super complexes.

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.

Undoubtedly, it is important to remain vigilant and manage invasive grasses to prevent their spread and mitigate their negative impact on the environment. However, these aggressive plants can also play a beneficial role in certain contexts. For example, several invasive grasses provide valuable forage for livestock and have disease control potential. Therefore, a research experiment was conducted to explore the pros and cons of this approach, not only for surrounding vegetation but also for human and animal disease control. The study is primarily focused on developing livestock feed, plant-derived herbicides, and an understanding of the phytotoxic effects of invasive species. All plant parts of Cenchrus ciliaris L., Polypogon monspeliansis L., and Dicanthium annulatum (Forssk.) Stapf, were tested for their phyto-chemical screening, proximate, and toxicity analysis which was caused by the methanolic extract of these grass species. Qualitative phytochemical screening tests were performed for proximate composition analysis and toxicity assessment essays. The phytochemical analysis revealed the positive results for alkaloids, flavonoids, coumarins, phenols, saponins, and glycosides, while negative for tannins. Comparison of proximate analysis intimated maximum moisture (10.8%) and crude fat (4.1%) in P. monspeliensis, whereas maximum dry matter (84.1%), crude protein (13.95%), crude fiber (11%), and ash (7.2%) in D. annulatum. Five (10, 100, 500, 100, 10,000 ppm) and three (10, 1000, 10,000 ppm) different concentrations of methanolic extract prepared from C. ciliaris, P. monspeliansis, and D. annulatum were used respectively for root inhibition and seed germination essay. Furthermore, three different concentrations (10, 30, 50 mg) of plant fine powder were used for sandwich method test. There was a significant decline in the growth rate of experimental model radish seeds (P > 0.005), and results from sandwich method tests showed suppressed growth of root hairs, inhibiting the anchoring of the radish seed. In comparison, results manifest that; P. monspeliansis indicated an upsurge of inhibition (66.58% at 10,000 ppm), D. annulatum revealed soar germination (75.86% in controlled conditions), and C. ciliaris exhibited dramatic shoot up of inhibition because of sandwich method test (14.02% at 50 mg). In conclusion, although grasses are toxic, it is important to consider the beneficiary account.

The stress of transplanting injury adversely affects rice growth and productivity worldwide. N-acetylcysteine (NAC), the precursor of glutathione, is a potent ROS scavenger with powerful antioxidant activity. Previous studies on the application of NAC in plants mainly focused on alleviating the stress of heavy metals, UV-B, herbicides, etc. However, the role of NAC in alleviating transplanting injury is still not clear. A barrel experiment was carried out to explain the mechanism of NAC regulating the transplanting injury to machine-transplanted rice during the recovery stage. The results showed that NAC priming shortened the time of initiation of tillering and increased the tiller numbers within 3 weeks after transplanting. In addition, NAC priming increased the chlorophyll content, net photosynthetic rate, and sucrose content, thereby improving the dry weight at the recovery stage, especially root dry weight. At the same time, NAC priming significantly increased the activity of ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), and superoxide dismutase (SOD). In addition, it also regulated flavonoids and total phenols contents to reduce hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) contents, especially at the initial days after transplanting. These results suggest that NAC priming improves the tolerance of rice seedlings against transplanting injury by enhancing photosynthesis and antioxidant systems at initial days after transplanting, thereby promoting the accumulation of dry matter and tillering for higher yield returns.