This study explored the changes in senescence patterns and vase life of cut roses grown in summer and autumn, aiming to identify the relationship between harvest seasons and flower longevity. We analyzed gene expression profiles associated with lignin, pectin, ethylene, auxin, and sucrose transport to understand the molecular mechanisms underlying senescence symptoms, such as the bent neck, petal abscission, and petal wilting in cut rose flowers. Our results revealed season-dependent occurrences of bent neck and petal abscission, with higher incidence rates in autumn-harvested rose flowers. These increases in bent neck and petal abscission contributed to a shortened vase life for the cut flowers. Gene expression analysis indicated that elevated levels of ethylene biosynthesis genes and reduced expression of lignin, pectin biosynthesis, auxin response factor, and sucrose transport genes accelerated the increased senescence symptoms. Notably, the incidence rates of the bent neck were highly negatively correlated with the transcript levels of key genes involved in lignin and pectin biosynthesis, RhPRXPX and RhGAUT1, in pedicels. These findings contribute to our understanding of the molecular factors influencing the mechanical strength of flower pedicels and provide insights for postharvest strategies to enhance the ornamental value of cut flowers across seasons.

The effects of light intensity and external sucrose on the vase life of cut roses were estimated by monitoring the net photosynthesis and chlorophyll fluorescence. Cut flowers were held under different light intensities 10 (L10) or 50 (L50) μmol‧m-2‧s-1 with or without treatment with external sucrose. We found substantial differences in stomatal conductance, photosynthesis rate, photosystem II (PSII) quantum efficiencies, specific fluxes, and vase life of the cut flowers when exposed to different light intensities. Light intensity at 50 μmol‧m-2‧s-1 increased photosynthesis capacity, thus delaying petal senescence and extending the vase life of cut flowers. L50 flowers maintained a high photosynthetic rate by reducing heat dissipation (DI0/RC) and increasing electron transport (ET0/TR0 and ET0/ABS) in the electron transport chain of the photosynthesis apparatus. The application of external sucrose extended the vase life of cut flowers by improving water balance and sustaining turgor pressure in the petals of the cut flowers. The net rate of photosynthesis of the cut flowers was increased by higher light intensity; however, it was not affected by the application of external sucrose. Our results indicate that the application of external sucrose is necessary to improve the longevity of cut flowers when endogenous sucrose production by photosynthesis is insufficient under low light conditions during the postharvest period. In addition, our results revealed that most of the photosynthetic parameters were significantly correlated with the vase life of cut rose flowers. Moreover, the relation between the rate of photosynthesis and chlorophyll fluorescence parameters indicates that the rise from the basic dark-adapted fluorescence yield to the maximum (OJIP transient) method can be used as a tool for the evaluation and prediction of the photosynthesis rate in cut flowers.

Gray mold is caused by the fungal pathogen Botrytis cinerea (B. cinerea), a commercially damaging disease of rose flowers. The infection of this necrotrophic fungal pathogen is one of the most important reason that rose flower is rejected by consumers and importers, leading to economic losses. The gray mold disease influences rose flowers through cultivation and distribution in the greenhouse, storage, transport, and market. Environmental conditions and genetic factors are two primary factors that affect the development of gray mold in the flowers during pre- and postharvest stages. However, the interaction between B. cinerea and rose flowers at the molecular level has not been well studied to date. Despite the multiple studies conducted over the past decades, breeding flowers that have resistance to B. cinerea has not been successful in roses. Furthermore, the mechanism underlying tolerance to gray mold is under-investigated and poorly understood in roses. The most popular current control strategies against B. cinerea in roses are pre- and postharvest fungicides, but they are generally expensive, ineffective, and polluted. In this review, we summarized the nature of B. cinerea in plants and discussed the current control strategies of gray mold disease in rose flowers, such as radiation, resistance inducer, chemical and biological control. In addition, we propose an approach for reducing B. cinerea infection in rose flowers by using ethylene antagonists.

Ethylene-mediated premature floral senescence influences the postharvest quality and longevity of rose flowers. In recent years, studies have unveiled the action of ethylene during the development and senescence of rose flowers. However, despite the evidence that ethylene is highly produced in ethylene-sensitive roses, there is not always a direct interrelationship between ethylene sensitivity and rose flower longevity. In addition, ethylene sensitivity and ethylene-related gene expressions in roses are still not clearly understood. In this review, we summarized and discussed ethylene synthesis and sensitivity, role of ethylene-related genes, and impacts of ethylene on the postharvest quality of cut roses. By combining the mechanism of ethylene biosynthesis and signaling with ethylene sensitivity, we also highlighted the potential use of ethylene inhibitors for ethylene control and to improve the postharvest quality of cut rose flowers. We believe that this review will provide sufficient information about ethylene biology in rose flowers and contribute in developing effective methods to extend the postharvest life of roses by preventing ethylene damage.

Botrytis cinerea is a necrotrophic pathogen that significantly reduced the postharvest quality and longevity of cut roses. The aim of this study was to examine the effects of nano silver, sodium hypochlorite (NaOCl), and salicylic acid on B. cinerea infection in cut rose flowers. Cut ‘Revival’ roses were treated with nano silver, NaOCl, salicylic acid, and distilled water, and simultaneously held in the solutions. Subsequently, the cut flowers were sprayed with B. cinerea solution and held under export conditions for 4 days. The results showed that nano silver was the most effective treatment in suppressing B. cinerea growth in cut roses during vase life. Nano silver effectively extended the vase life of cut roses by 2.3 days, compared with non-treated flowers. The addition of nano silver also enhanced water uptake and sustained the water balance and fresh weight of the cut rose flowers. Our results indicated that nano silver is an effective treatment solution to inhibit B. cinerea infection and improve postharvest quality and longevity of cut rose flowers for export.

After harvest, Dolcetto cut roses were immediately exposed to air for 0 (E-0), 1 (E-1), 2 (E-2), and 3 h (E-3) and then placed under tap water for recovery. We determined the effect of air exposure time on vase life, water relations, and gene expression of cut flowers. The results revealed that E-0 treatment exhibits a higher postharvest quality of cut flowers than others. E-3 treatment significantly decreased the vase l ife of c ut r oses d ue t o an early f ailure o f water relations, such as larger stomatal size, higher transpiration, shorter time maintaining positive water balance, and the bacterial proliferation. E-0 treatment significantly decreased water stress, maintained leaf chlorophyll fluorescence ratios, and extended the vase life of cut roses. The decrease in water stress of E-0 treated flowers may increase the expression of Rh-PIP2;1 and Rh-TIP in rose petals, resulting in maintained cell turgor and increased flower diameter of cut flowers. These results recommend that a non-exposed harvest can be used for the harvest s tage to improve the postharvest quality of cut flowers. Understanding the relationship between air exposure time and water relations of cut flowers will significantly help in developing distribution systems for assuring cut roses quality.

We examined the efficacy of various pretreatment solutions on the postharvest longevity and quality of ‘Hessa’ cut spray roses (Rosa hybrida L.) to develop an inexpensive and innocuous preservative solution for the cut flower industry. Cut flowers were pretreated with 4 preservatives for 10 hours: Scutellaria baicalensis Georgi extract (SC) at 300 μL·L-1, hydrosol (H), S. baicalensis Georgi extract 300 μL·L-1 + sucrose 1% (SC + Suc), and H + sucrose 1% (H + Suc). The results showed that pretreatment with all the solutions except H + Suc improved the postharvest longevity and extended the longevity of cut rose flowers. We found that 300 μL·L-1 of SC was the most effective preservative, which significantly prolonged the postharvest longevity in cut flowers from 9.7 days (control) to 14.1 days. The beneficial effects of 300 μL·L-1 SC pretreatment were associated with inhibition of bacterial accumulation at the basal portion of cut stems, enhanced water uptake, improved fresh weight, and a positive water balance. SC also effectively maintained chlorophyll fluorescence ratios in the leaves and reduced water stress in cut roses. The results demonstrate the potential of SC as an alternative preservative in the cut rose flower industry.

Cut roses often have a short vase life due to water stress and ethylene damage under unfavorable postharvest conditions. In this study, we investigated the effect of various pretreatment solutions on the vase life and postharvest quality of the cut rose cultivar ‘Jinny’ (Rosa hybrida L.). Cut roses were pretreated with eight different preservative solutions for 10 hours: aluminum sulfate (AS), Chrysal (CHR), FloraLife (FLR), lysosome (LYS), MS-1 (MS1), MS-2 (MS2), silver n itrate ( SN), a nd s ilver t hiosulfate ( STS). We found that pretreatment with all solutions except LYS prolonged the vase life and improved the postharvest quality of the cut roses. Among these, STS was the most effective pretreatment solution, significantly extending the vase life from 11.8 days (control) to 19.9 days, retaining the initial fresh weight and a positive water balance for longer, and inhibiting microbial growth in the vase. STS also enhanced the water uptake rate, and maintained the high chlorophyll and soluble sucrose contents in the leaves of the cut rose flowers. In addition, we found that MS1 and MS2, which are natural plant extracts, had strong antimicrobial effects and consequently prolonged the vase life of cut roses by more than 4 days compared with the control. Therefore, MS1 and MS2 can be considered as alternative preservatives in the cut flower industry.