Postharvest application of single, multi-walled carbon nanotubes and nanographene oxide improves rose keeping quality

ABSTRACT

Keeping quality is frequently terminated by adverse water relations or oxidative stress. This study was designed to evaluate whether postharvest application of single, multi-walled carbon nanotubes and nanographene oxide (SWCNTs, MWCNTs, and NGO respectively) can improve keeping quality in rose, along with the processes involved. Dose-response curves were realised by applying five concentrations of SWCNTs, MWCNTs, and NGO (0–80, 0–80, and 0–2 mg L⁻¹ respectively) either once as a foliar spray or continuously in the holding solution of different rose cultivars. At optimal concentration, CNTs and NGO through either application method extended keeping quality. CNTs improved water balance by promoting water uptake more than water loss, whereas NGO did not. Each nanomaterial at optimal concentration was also employed to assess various parameters underlying keeping quality. CNTs generally enhanced leaf stomatal conductance and transpiration. CNTs and NGO attenuated chlorophyll degradation, electrolyte leakage and lipid peroxidation due to the amplified triggering of both enzymatic and non-enzymatic antioxidants. In conclusion, the extension of keeping quality by postharvest application of CNTs and NGO was characterised by different modes of action. Both upgraded the antioxidant status, while CNTs additionally promoted water relations.Abbreviations: APX, ascorbate peroxidase; CAT, catalase; CNTs, carbon nanotubes; DW, dry weight; FW, fresh weight; GAE, gallic acid equivalent; NGO, nanographene oxide; MDA, malondialdehyde; MWCNTs, multi-walled CNTs; NBT, nitro-blue tetrazolium chloride; POD, peroxidase; RH, relative air humidity; ROS, reactive oxygen species; RUE, rutin equivalent; RWC, relative water content; SOD, superoxide dismutase; SWCNTs, single-walled CNTs.

KEYWORDS:

• Antioxidants
• nanomaterials
• Rosa hybrida
• turgidity
• vase life
• water relations

Acknowledgments

This research was financed by Lorestan University (Iran). We are grateful to the laboratory staff for their contributions, continued diligence, and dedication to their craft. The valuable comments of the editor and two anonymous reviewers are greatly acknowledged.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Credit authorship contribution statement

MAM performed the experimental work. MAM and SMF carried out the data analysis and interpretation. ARN and DF designed and supervised the study. All authors have read and agreed to the final version of the manuscript.

Highlights

• Postharvest application through foliar spray or the holding solution was performed.

• CNTs and NGO stimulated cut rose vase life.

• CNTs enhanced leaf, petal and cut flower turgidity.

• CNTs and NGO attenuated chlorophyll degradation and lipid peroxidation.

• CNTs and NGO upgraded both enzymatic and non-enzymatic antioxidant status.