Nanopriming as an approach to induce tolerance against drought stress in wheat cultivars
摘要
The demand for compounds that enhance stress tolerance is growing, as they are essential for mitigating the detrimental impacts of adverse stressful conditions. Some of these compounds not only provide a protective effect against stress but also have the ability to promote plant growth. This study was developed to emphasize the effects of seed priming using hydro and varying concentrations of zinc oxide nanoparticles (0.05, 0.1, 0.25, 0.5, and 1.0 g/L) on certain evaluations in two wheat cultivars, Masr1, which is drought tolerant, and Gemmeiza9, which is drought sensitive, across different field capacity levels (80, 60, 40, and 20%). Leaf area, specific root length, relative water content, some metabolites (primary and secondary), antioxidant activity and gene expression were evaluated in this study. The most interesting aspect is the ratio between root length and dry weight (specific root length), which increased in both cultivars under stress. This may indicate that the plant root increased in size to face drought stress and the reduction with priming may indicate the alleviation in stress. Our results revealed that the application of hydropriming and nanopriming can significantly alleviate adverse effects of drought stress on growth of wheat through modification in relative water content. Some osmolytes (protein, proline, and total soluble sugars) in addition to the increase in antioxidant (2, 2-Diphenyl-1-picrylhydrazyl and phenolic compounds) play an important role in osmotic adjustment and decrease the free radicle, which causes damage to the plant tissue. Soluble protein content increased in response to nanoparticles under drought stress but not in well-watered conditions in both wheat cultivars, and the application of nanoparticles at 40% field capacity induced a stress resistant protein band. This result is compatible with the physiological and biochemical results. Herein, we investigated the involvement of protein synthesis and metabolism in the process of zinc oxide nanoparticles induced drought tolerance in wheat cultivars. This opens an unusual perspective on plant modification due to nanopriming effect that should be tested in other crop species.