Brassinosteroids Alleviate Heat-Induced Inhibition of Photosynthesis by Increasing Carboxylation Efficiency and Enhancing Antioxidant Systems in Lycopersicon esculentum

Exogenous application of brassinolide can alter morphological and physiological traits of Leymus chinensis (Trin.) Tzvelev under room and high temperatures

“…An increased level of MDA was observed in L. chinensis plants by the effect of high temperature stress, which is an index of lipid peroxidation and damage of biological membranes but the treatment with BR lowered the MDA content under normal and stressed conditions ( Table 4). The said observations are in accordance with Ogweno et al (2008) who reported that there was an enhanced production of MDA by the heat treatments of tomato; however, 24-epibrassinolide application reduced the MDA level in plants. There was excessive production of proline, soluble protein and sugar content in L. chinensis plants under the high temperature stress which was further improved by the application of BR with most beneficial results obtained at 0.1 mg L -1 concentration (Table 4).…”

“…The activity of the antioxidant enzymes is very crucial for scavenging the reactive oxygen species, whose production is increased under the stressed conditions (Gapper and Dolan, 2006). Reactive oxygen species are quenched by antioxidant enzymes and BR induces the activity of antioxidant enzymes (Ogweno et al, 2008). The enhanced biosynthesis and activity of antioxidant enzymes is attributed to increased transcription of genes encoding mRNA for antioxidant enzymes (Bajguz and Hayat, 2009).…”

Effects of 24-epibrassinolide Pre-treatment on UV-B-Induced Changes in the Pigment Content of Pea Leaves

“…It has been shown that the EBR application exerts a direct role in the regulation of plant photosynthesis [ 2 ]. Several studies have also reported the role of EBR in the protection of photosynthetic apparatus against environmental stresses by enhancing plant tolerance to abiotic stresses [ 1,[3][4][5] ]. Brassinosteroid-enhanced stress tolerance was proposed to relate to increased activity of the reactive oxygen species scavenging system -antioxidant enzymes (via accumulation of abscisic acid) and with increased content of ascorbic acid and carotenoids [ 1,3,5 ].…”

“…RAN1) were grown as water culture at controlled conditions under light intensity 100 µmol photons m −2 s −1 with 10 h light/14 h dark photoperiod at room temperature. Pea plants (12-days old) were sprayed with 0.1 mg L −1 24-epibrassinolide (EBR, Sigma-Aldrich) or distilled water as described previously [ 3 ]. 48 h after EBR application, the plants were subjected for 3 h to UV irradiation at room temperature and then transferred back to control light/dark conditions and kept for 24 and 48 h. As a source of UV-B irradiation, fluorescent tubes with emission at 312 (±25 nm) (TL 20W/12 R, Philips, Hamburg, Germany) were used.…”

“…In this study, pea plants were sprayed with 0.1 mg L −1 EBR 48 h before starting of UV-B treatment since it was previously shown that EBR has greatest effect under these conditions [ 2,3 ]. The effects of EBR on the plant tolerance to UV-B exposure were evaluated by changes in the content of the main photosynthetic pigments (Chl a, b, total Car) and in the content of anthocyanins and UV-B absorbing compounds, measured 24 and 48 h after irradiation.…”