تاثیر نانوذرات دی‌اکسید تیتانیوم بر ویژگی‌های مورفوفیزیولوژیکی گل شاخه بریده رز

نوع مقاله : مقاله پژوهشی

نویسندگان

• حمید سلیمانی
• مسعود ارغوانی
• میترا اعلائی

گروه علوم باغبانی، دانشکده کشاورزی، دانشگاه زنجان، زنجان، ایران.

چکیده

کلیدواژه‌ها

• آنزیم‌های آنتی‌اکسیدان
• انسداد آوندی
• عمر پس از برداشت
• نانو ذرات

موضوعات

• علوم گیاهان زینتی

عنوان مقاله [English]

Effect of Titanium Dioxide Nanoparticles on Morphophysiological Characteristics of Cut Rose Flowers

نویسندگان [English]

• Hamid Soleymani
• Masoud Arghavani
• Mitra Aelaei

کلیدواژه‌ها [English]

• Antioxidant enzymes
• Nanoparticle
• Postharvest life
• Xylem occlusion

Extended Abstract

Introduction

Roses are among the most significant ornamental flowers in the global floriculture industry, particularly prized as cut flowers due to their beauty, fragrance, and commercial value. However, one of the persistent challenges faced by producers and distributors is the decline in post-harvest quality, primarily due to improper storage and handling conditions after harvesting. This deterioration can result in substantial economic losses and reduced customer satisfaction. As a result, there has been growing interest in identifying substances and methods that can enhance the post-harvest quality and shelf life of cut flowers. In recent years, nanotechnology has emerged as a powerful tool in agricultural and horticultural sciences. Nanoparticles, materials with dimensions less than 100 nanometers, have demonstrated unique physicochemical properties that can be exploited to improve plant growth, resistance to stress, and post-harvest performance. Titanium dioxide (TiO₂) nanoparticles, in particular, have garnered considerable attention due to their high stability, photocatalytic activity, and role in enhancing physiological responses in plants. These nanoparticles have been shown to influence various biochemical and morphological traits, making them a potential candidate for improving the quality and longevity of cut flowers. In the present study, the pre-harvest foliar application of titanium dioxide nanoparticles was evaluated for its effects on the morpho-physiological characteristics and vase life of rose cut flowers (cultivar: Classic Cezanne). The objective was to determine whether TiO₂ nanoparticles could enhance post-harvest quality traits and extend the freshness of cut roses.

Materials and methods

This research was conducted during the 2021 growing season in a commercial rose greenhouse located in Nazarabad city, Alborz province, Iran. Titanium dioxide nanoparticles were applied at three different concentrations: 0 mg·L⁻¹ (control), 5 mg·L⁻¹, and 10 mg·L⁻¹. The nanoparticles were sprayed onto rose bushes at ten-day intervals starting two months prior to the harvest date. The goal of this pre-harvest application was to allow sufficient time for physiological responses to develop. Following harvest, the flowers were carefully transported to the laboratory for evaluation. Several morpho-physiological and biochemical parameters were measured on days 0, 4, 8, and 12 of vase life. These traits included vase life duration, flower diameter, fresh weight, uptake of vase solution, total soluble solids (TSS), electrolyte leakage, petal anthocyanin content, total protein content, and levels of malondialdehyde (MDA), a marker of oxidative stress and membrane damage. Additionally, the activity levels of two important antioxidant enzymes, peroxidase (POD) and superoxide dismutase (SOD), were measured as indicators of the plant’s defense response. The experimental design followed a factorial arrangement based on a completely randomized design (CRD), with three replications for each treatment. Data were analyzed statistically using analysis of variance (ANOVA), and significant differences between means were determined using Duncan’s multiple range test at the 1% probability level.

Results and Discussion

The analysis of variance showed that titanium dioxide nanoparticle treatments had a significant effect (p < 0.01) on the majority of traits related to post-harvest quality. Notably, the 10 mg·L⁻¹ TiO₂ treatment resulted in the longest vase life, averaging 12 days, compared to only 7 days in the control group. This suggests that TiO₂ nanoparticles play a role in delaying senescence and maintaining flower freshness. In terms of morphological characteristics, the flowers treated with 10 mg·L⁻¹ of TiO₂ nanoparticles exhibited a 35.7% increase in flower diameter and a 20.4% increase in fresh weight compared to the control. These improvements likely reflect better water status, cellular turgor, and metabolic activity in treated plants. Additionally, the uptake of vase solution increased by 35% in the 10 mg·L⁻¹ treatment group, indicating enhanced water transport and reduced xylem blockage, common causes of early wilting in cut flowers. The higher uptake rates are likely correlated with the increased activity of antioxidant enzymes, which can protect vascular tissues from oxidative damage. From a biochemical perspective, the total protein content and superoxide dismutase activity were significantly elevated in flowers treated with titanium dioxide nanoparticles. SOD activity increased by 1.36%, reflecting improved stress tolerance and detoxification of reactive oxygen species (ROS). Meanwhile, MDA content was reduced, signaling decreased membrane lipid peroxidation and better cell membrane stability. These results support the hypothesis that titanium dioxide nanoparticles activate protective physiological pathways, enhancing the flower’s ability to maintain quality during post-harvest storage. The observed improvements in both structural and biochemical attributes suggest that TiO₂ nanoparticles help preserve freshness by promoting water balance, delaying senescence, and boosting internal defense mechanisms.

Conclusion

The findings of this study demonstrate that pre-harvest foliar application of titanium dioxide nanoparticles, particularly at a concentration of 10 mg·L⁻¹, can significantly improve the post-harvest quality of rose cut flowers. This treatment extended vase life, enhanced flower diameter and fresh weight, improved water uptake, and strengthened the plant’s antioxidant defense system. The increase in total protein and superoxide dismutase activity, along with the reduction in malondialdehyde levels, indicates a clear improvement in stress resistance and physiological stability. Overall, the application of TiO₂ nanoparticles appears to be an effective, non-toxic, and practical approach to enhance the market value and shelf life of cut roses. These results offer a promising strategy for commercial rose producers seeking to improve flower quality and reduce post-harvest losses. Further research could explore the underlying molecular mechanisms and evaluate the efficacy of TiO₂ nanoparticles under different environmental conditions and in other flower cultivars.