Impact of silicon on maize seedlings exposed to short-term UV-B irradiation

Abstract

Enhanced UV-B irradiation is one of the most important abiotic stresses that can influence various aspects of plant morphology, biochemistry and physiology. Silicon as a beneficial element can increase the plant's tolerance against different abiotic stresses, including UV-B stress. In this work, the effect of silicon supplementation on the sensitivity of young maize (Zea mays L.) seedlings exposed to short-term UV-B radiation was studied. The seedlings were grown with 0 or 5 mM silicon in cultivation medium and on the fifth day of cultivation, they were exposed for 15 and 30 min to UV-B (302 nm) radiation. No significant changes in growth and content of assimilation pigments and the chlorophyll a/b ratio were observed in any of tested irradiation periods in control or Si-treated plants. Under UV-B stress, the content of ROS (hydrogen peroxide and superoxide radical) and TBARS increased in control plants. The oxidative status of Si-treated plants was only slightly affected even after 30 min. Phenolic metabolites (total phenols and flavonoids), important for their screening function under radiation stress, slightly increased after UV-B exposure in control plants, however, only flavonoids increased after 30 min in Si-treated plants. The measured parameters indicated that to some extent silicon supplementation contributes to higher UV-B tolerance of maize seedlings.

Molecular Effects of Silicon on Arabidopsis thaliana Seedlings under UV‐B Stress

“…Silicone can be applied to plants in many different forms. In the studies, it has been seen that silicon is applied in the forms of potassium silicate (28), silicon nanoparticles (18), sodium silicate (23), and silicic acid (20). Since silicon is taken from the soil by plants in the form of orthosilicic acid and is widely used in this form in in vitro studies, it is preferred in the form of orthosilicic acid for the current study.…”

“…The effects of UV-B and silicon on high silicon accumulators such as rice (29), corn (23), wheat (18), and soybean (20) were investigated, and A. thaliana, a model organism as a low silicon accumulator, has not been included in a recent study on UV-B and silicon together. Hence, A. thaliana was selected within the scope of the study.…”

Silicon Mitigates Negative Impacts of Drought and UV-B Radiation in Plants

“…Studies regarding the addition of Si or Si nanoparticles have been reported for crop plants such as rice, wheat, and soybean ( Glycine max L.) ( Table 2 ). Such studies have shown that Si can reduce the negative effects of UV radiation through increased antioxidant capacity [ 3 , 4 ] and lower concentrations of ROS [ 5 ].…”

“…Mihaličová Malčovská et al [ 5 ] exposed maize seedlings to short-term UV-B radiation. The seedlings were grown hydroponically and treated with Si or left untreated, as the control.…”

“…Silicon (Si) treatment of plants has been shown to mitigate some of the negative impacts of drought and enhanced UV-B radiation. In plants exposed to UV-B, Si can increase the activity of the photosynthetic apparatus, decrease the transpiration rate, increase the antioxidant capacity [ 3 , 4 ], and lower the concentrations of reactive oxygen species (ROS) [ 5 ] and protective phenol substances, in comparison to plants exposed to UV-B without Si treatment [ 4 ]. Similarly, during drought, Si can increase plant growth, relative water content, photosynthesis rate, and chlorophyll content, and affects other physiological responses [ 6 ].…”