Synergistic Exposure of Rice Seeds to Different Doses ofγ-Ray and Salinity Stress Resulted in Increased Antioxidant Enzyme Activities and Gene-Specific Modulation of TC-NER Pathway

Abstract

Recent reports have underlined the potential of gamma (γ)-rays as tools for seed priming, a process used in seed industry to increase seed vigor and to enhance plant tolerance to biotic/abiotic stresses. However, the impact of γ-rays on key aspects of plant metabolism still needs to be carefully evaluated. In the present study, rice seeds were challenged with different doses of γ-rays and grown in absence/presence of NaCl to assess the impact of these treatments on the early stages of plant life. Enhanced germination efficiency associated with increase in radicle and hypocotyl length was observed, while at later stages no increase in plant tolerance to salinity stress was evident. APX, CAT, and GR were enhanced at transcriptional level and in terms of enzyme activity, indicating the activation of antioxidant defence. The profiles of DNA damage accumulation were obtained using SCGE and the implication of TC-NER pathway in DNA damage sensing and repair mechanisms is discussed. OsXPB2, OsXPD, OsTFIIS, and OsTFIIS-like genes showed differential modulation in seedlings and plantlets in response to γ-irradiation and salinity stress. Altogether, the synergistic exposure to γ-rays and NaCl resulted in enhanced oxidative stress and proper activation of antioxidant mechanisms, thus being compatible with plant survival.

Pulsed electromagnetic field – a cultivation practice used to increase soybean seed germination and yield

“…Activating plant growth and germination can be accelerated by using an optimum frequency (Aladjadjiyan, 2007). The results of Macovei et al (2014) showed that different frequencies can have a stimulating or an inhibitory effect. The research indicates that a wave length can positively influence sprouting and root length of one hybrid, whereas it can have repressive effects on another hybrid (Dicu, Pirsan, 2014).…”

Pretreatment with low-dose gamma irradiation enhances tolerance to the stress of cadmium and lead in Arabidopsis thaliana seedlings

“…It has been reported that the activities of antioxidant enzymes, such as POD, SOD, or CAT, are stimulated in plants exposed to low-dose gamma irradiation (Croci et al, 1991;Kim et al, 2011). In addition, gamma irradiation at low doses up-regulates the gene expression profiles of antioxidant enzymes in response to salt stress (Macovei et al 2014). Taken together, our results suggest that the increased activities of SOD, POD, and CAT induced by low-dose gamma irradiation contribute to scavenging the excess ROS produced under Cd/Pb stress.…”

Role of Jasmonic Acid and Gamma Radiation in Alleviating Salt Stress in Moringa

“…A synergistic treatment by γ-rays and NaCl enhanced oxidative stress and activate antioxidant mechanisms, which reinforce cell components, subsequently being perfect with plant survival (Macovei et al, 2014).…”