Abstract
ABSTRACT This study evaluates the influences of nickel and ozone exposure individually and/ or in combination on growth performance, antioxidant activity and genes up regulation of two rice cultivars Sakha 101 and Giza 178. Ni treatment at high doses (100 µM Ni) and 75 ppb O3 alone reduced the fresh weight, mineral content, membrane integrity and Rubisco content. There was an increase in SOD and APX activity in the shoots of rice cultivars, whereas, there was a decrease in GR and GST in the roots and shoots. In contrast combined stresses appeared to be stimulatory for growth and mineral contents, Rubisco content and antioxidant enzymes. Nonspecific lipid transfer protein and transmembrane protein genes were up regulation in rice cultivars in response to Ni stress. Carotenoid cleavage dioxygenase is upregulated in response to ozone stress; RNA pseudouridine synthase, heat shock proteins and cytochrome P450-like were upregulated in response to combined stresses. The results revealed that the interactive effects of both stresses were antagonistic on growth parameters and antioxidant activities to overcome the adverse effects of both pollutants.
Highlights
Nickel is required for iron absorption, seed germination and its deficiency leads to the production of viable seeds in plants
It is well noted that fumigation by 75 ppb/h ozone showed a significant reduction in the fresh weight of shoots by 42% and 53% of the relevant control values for Sakha 101 and Giza 178 (Table 2)
These observations might indicate that the Giza 178 cultivar was relatively more sensitive to nickel and ozone stresses than the Sakha 101 cultivar
Summary
Nickel is required for iron absorption, seed germination and its deficiency leads to the production of viable seeds in plants. Application of nickel to crops protects them from certain yield limiting diseases, potentially reducing pesticide usage and improving crop yield. Nickel (Ni2+) acts as a biocontrol agent for microbial pests. It is a key factor affecting the production of secondary plant metabolites and influencing plant resistance to diseases (Wood and Reilly 2007). Maize could be used as the indicator plant for the environment quality assessment for Ni, lettuce is the most tolerant to increasing nickel doses, whereas maize is the most sensitive (Antonkiewicz et al 2016)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
