Search Results (129)

The premature senescence of red raspberry leaves severely affects plant growth. In this study, the double-season red raspberry cultivar ‘Polka’ was used, with N₁₅₀ (0.10 g N·kg⁻¹) selected as the treatment group (T150) and N₀ (0 g N·kg⁻¹) set as the control (CK). This study systematically investigated the mechanism of premature senescence in red raspberry leaves under different nitrogen application levels by measuring physiological parameters and conducting a combined multi-omics analysis of transcriptomics and metabolomics. Results showed that T150 plants had 8.34 cm greater height and 1.45 cm greater ground diameter than CK. The chlorophyll, carotenoid, soluble protein, and sugar contents in all leaf parts of T150 were significantly higher than those in CK, whereas soluble starch contents were lower. Malondialdehyde (MDA) content and superoxide anion (O₂⁻) generation rate in the lower leaves of T150 were significantly lower than those in CK. Superoxide sismutase (SOD) and peroxidase (POD) activities in the middle and lower functional leaves of T150 were higher than in CK, while catalase (CAT) activity was lower. Transcriptomic analysis identified 4350 significantly differentially expressed genes, including 2062 upregulated and 2288 downregulated genes. Metabolomic analysis identified 135 differential metabolites, out of which 60 were upregulated and 75 were downregulated. Integrated transcriptomic and metabolomic analysis showed enrichment in the phenylpropanoid biosynthesis (ko00940) and flavonoid biosynthesis (ko00941) pathways, with the former acting as an upstream pathway of the latter. A premature senescence pathway was established, and two key metabolites were identified: chlorogenic acid content decreased, and naringenin chalcone content increased in early senescent leaves, suggesting their pivotal roles in the early senescence of red raspberry leaves. Modulating chlorogenic acid and naringenin chalcone levels could delay premature senescence. Optimizing fertilization strategies may thus reduce senescence risk and enhance the productivity, profitability, and sustainability of the red raspberry industry. Full article

The aim of this study was to investigate the preferences of young adults in the Polish apple market in response to the declining consumption of these fruits. To address the research questions, a study was conducted among young adults using a custom-designed online questionnaire. The research sample consisted of 729 participants. The data were analyzed using ANOVA, and due to the nature of the data, Wilcoxon tests were also employed to examine differences. The most frequently purchased fruits among young adults were bananas and apples; however, strawberries and raspberries were the most favored. The most preferred apple cultivars were bicolored (e.g., Jonagored) and red (e.g., Gala Royal), while yellow cultivars (e.g., Golden Delicious) were perceived as the least attractive. Young consumers favored apples that were juicy, firm, and moderately sweet. This study demonstrated that the skin color of an apple was associated with expectations regarding its firmness and sweetness. Apples with intense coloration (dark red and green) received the highest valuations, particularly when organically grown. In contrast, apples from conventional production systems were valued below their market price by young consumers, indicating the need for strategies aimed at enhancing their perceived value. Full article

Fire is a destructive hazard impacting residential, industrial, and forested environments. Once ignited, fire becomes difficult to control, and recovery efforts are often extensive. Therefore, early detection is critical for effective firefighting. This study presents a mobile robotic system designed for early fire detection, integrating a Raspberry Pi, RGB (red, green and blue), and night vision-NIR (near infrared reflectance) cameras. A four-stage hybrid-cascade machine learning model was developed by combining state-of-the-art (SotA) models separately trained on RGB and NIR images. The system accounts for both daytime and nighttime conditions, achieving F1 scores of 96.7% and 95.9%, respectively, on labeled fire/non-fire datasets. Unlike previous single-stage or two-stage vision pipelines, our work delivers a lightweight four-stage hybrid cascade that jointly fuses RGB and NIR imagery, integrates temporal consistency via ConvLSTM, and projects a robot-centric “safe-approach distance” in real time, establishing a novel edge-level solution for mobile robotic fire detection. Based on real-life test results, the robotic system with this new hybrid-cascade model could detect the fire source from a safe distance of 500 mm and with notably higher accuracy compared to structures with other models. Full article

This study aims to develop a real-time gas leak detection system for application in gas cylinder filling machines. To promptly recover gas during leakage incidents, the efficiency of the gas filling process was improved by reducing resource wastage. The system utilized a Raspberry Pi with a camera for image-based detection and employed the dark channel prior method to detect the presence of gas. The message queue system was used for the real-time data transmission of gas leak status, temperature, and humidity data. The system sent data to a central server via message queuing telemetry transport (MTQQ). Node-RED was used for data visualization and anomaly alerts. Machine learning methods such as support vector machines (SVMs) and decision trees were applied to analyze the correlation between gas leaks and other environmental parameters to predict leak incidents. This system effectively detected gas leakage and transmitted and analyzed the data, significantly improving the operational efficiency of the gas cylinder filling process. Full article

In order to achieve differentiated utilization of red raspberry fruit pulp, a widely targeted metabolomics analysis of pulp from two regions was performed to explore the effect of plateau environment on the accumulation of secondary metabolites of red raspberry. Ultra-high performance liquid chromatography–mass spectrometry (UHPLC-MS/MS), combined with principal component analysis and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), was used to process the data and correlate them with the results of four antioxidant assays. Fourteen metabolites were characterized in the fruit pulp of Qinghai raspberries, and 618 up-regulated differential metabolites were found, which was 4.35 times higher than that of Yunnan. Flavonoids and phenolic acids were more abundant, with kaempferol-3-O-sambubioside being endemic to Qinghai, and saccharin-7-O-glucoside and rhamnocereus citrinus being endemic to Yunnan. Metabolic pathway enrichment analysis showed that the fruit pulp from the two regions differed significantly (p < 0.01) in ATP-binding cassette transporter (ABC transporter), purine metabolism, and so on. Antioxidant analysis showed that the Yunnan raspberries (Y-RP) were significantly superior to Qinghai raspberries (Q-RP) in terms of DPPH radical scavenging ability (DPPH) and ferric ion reducing/antioxidant power (FRAP), while Q-RP was significantly superior to Y-RP in terms of oxygen radical absorbance capacity (ORAC) and ABTS radical scavenging capacity (ABTS). This study showed that the plateau environment significantly promotes the accumulation of functional secondary metabolites of red raspberry, which provides a theoretical basis for the development of the functional components of plateau raspberry. Full article

In order to achieve accurate and rapid identification of red raspberry fruits in the complex environments of fields and greenhouses, this study proposes a new red raspberry maturity detection model based on YOLOv11n. First, the proposed hybrid attention mechanism HCSA (halo attention with channel and spatial attention modules) is embedded in the neck of the YOLOv11n network. This mechanism integrates halo, channel, and spatial attention to enhance feature extraction and representation in fruit detection and improve attention to spatial and channel information. Secondly, dilation-wise residual (DWR) is fused with the C3k2 module of the network and applied to the entire network structure to enhance feature extraction, multi-scale perception, and computational efficiency in red raspberry detection. Concurrently, the DWR module optimizes the learning process through residual connections, thereby enhancing the accuracy and real-time performance of the model. Finally, a lightweight and efficient dynamic upsampling module (DySample) is introduced between the backbone and neck of the network. This module enhances the network’s multi-scale feature extraction capabilities, reduces the interference of background noise, improves the recognition of structural details, and optimizes the spatial resolution of the image through the dynamic sampling mechanism. Reducing network parameters helps the model better capture the maturity characteristics of red raspberry fruits. Experiments were conducted on a custom-built 3167-image dataset of red raspberries, and the results demonstrated that the enhanced YOLOv11n model attained a precision of 0.922, mAP@0.5 of 0.925, and mAP@0.5 of 0.943, respectively, representing improvements of 0.7%, 4.4%, and 4.4%, respectively. At 3.4%, mAP@0.5-0.95 was 0.798, which was 2.0%, 9.8% and 3.7% higher than the original YOLOv11n model, respectively. The mAP@0.5 of unripe and ripe berries was 0.925 and 0.943, which was improved by 0.7% and 4.4%, respectively. The F1-score was enhanced to 0.89, while the computational complexity of the model was only 8.2 GFLOPs, thereby achieving a favorable balance between accuracy and efficiency. This research provides new technical support for precision agriculture and intelligent robotic harvesting. Full article

Red raspberries are valued for their color, flavor, and health-promoting organic compounds, which may be affected by increased temperatures due to climate change. This work aimed to provide new information on the response of raspberry cv. “Heritage” to thermal increase and its impact on fruit quality and perceived flavor. The study was conducted during two seasons in two locations with contrasting agroclimatic conditions. A zone with high background temperatures (central orchard) and low background temperatures (southern orchard) were studied. The treatments were three heating chambers installed at the fruit set, increasing the ambient temperature by ~4 °C, and untreated controls. Heat-treated raspberries were larger than the controls but showed softer fruit. Soluble solids were lower in treated fruit, while titratable acidity did not show a consistent pattern between treatments or orchards. Flavonoid content and anthocyanins did not present a clear pattern for both orchards and seasons. Heated raspberries had lower vitamin C in both years and orchards. The sensory analysis revealed differences only in color uniformity in the heated fruit from the central zone. Increased temperatures will affect the quality and nutritional aspects of the raspberries; however, at a sensory level, these changes may not be perceived. Full article

As an alternative to traditional red wine production during an economic crisis, we investigated the sensory perception and appreciation (liking) of young consumers for organic red grape juice from the Plantet cultivar (Seibel 5455) with or without the addition of sugar or organic acid. This was evaluated through four studies involving panels of young adults with an average age of 22 years. The goal was to determine how adding tartaric acid or hexoses (glucose and fructose) affected hedonic scores as well as gustatory and aromatic attributes. Surprisingly, adding acid to a must that experts deemed overly sweet (with 255 g/L of endogenous sugar in the control) did not improve liking scores. Similarly, the addition of hexoses did not enhance liking. Instead, natural grape juice, without any added sugar or acid, was the most preferred product among the young adult panelists. This preference was shared by a panel of enology students, who can be considered future key decision makers in the wine and juice industries, in the last study. As expected, the addition of hexoses led to a perception of ‘jam’ and ‘sweet’ attributes, while the addition of tartaric acid resulted in a more ‘acidic’ profile. Interestingly, the fruit attributes most associated with hexose addition were ‘apricot’ and ’strawberry’, whereas tartaric acid addition was most strongly associated with ‘raspberry’. Full article

The raspberry-red grossular, discovered in the Sierra de Cruces in Coahuila, Mexico, is characterized by its zoned coloration, featuring a pink rim and a black mantle with a sharp color transition at the border. However, there is a notable lack of definitive and systematic identification characteristics pertaining to its special zones. The mineral chemical composition and chromogenic mechanism remain unsupported by empirical validation derived from specific experimental data. In this study, the gemological properties, chemical composition, and spectral characteristics are systematically analyzed to explore the chromogenic mechanism and formation of zonal genesis. The results of the X-ray diffraction pattern, Raman spectrum, and major elements’ composition show that the raspberry-red grossular samples are grossular with high purity. Mn ions are a direct coloring factor of the pink rim of the grossular samples, while Fe ions are chromogenic elements of the black mantle. The MnO content of the pink rim ranges from 0.15 wt% to 1.72 wt%. The FeO content of the black mantle ranges from 3.11 wt% to 5.09 wt%, which is generally higher than that of other parts. The trace element compositions reveal that the rim and core of samples were formed in an oxidative environment (δEu = 0.43–2.41), which could be derived from the hydrothermal metasomatic skarn (δ¹⁸O = 11.03–12.14); the mantles of samples were formed in a reducing environment (δEu = 0.42–0.85), which is consistent with the magmatic skarn (δ¹⁸O = 11.40–11.66). They also show that the surrounding rocks provide part of the compositional sources for the raspberry-red grossular and interact with the black mantle, which affects the formation of the pink rim. This study offers geological and mineral compositional insights, addressing a significant void in the study of raspberry-red grossular, and lays the foundation for follow-up investigations. Full article

In this study, biodegradable and active films based on sodium alginate incorporated with different concentrations of oils (25% and 50%) from fruit seeds were developed for potential applications in food packaging. The ultraviolet and visible (UV-VIS) spectra of raspberry seed oil (RSO) and black currant seed oil (BCSO) indicated differences in bioactive compounds, such as tocopherols, phenolic compounds, carotenoids, chlorophyll, and oxidative status (amounts of dienes, trienes, and tetraenes) of active components added to alginate films. The study encompassed the color, structure, and thermal stability analysis of sodium alginate films incorporated with RSO and BCSO and their mixtures. The color of alginate films before and after the addition of oils from both fruit seeds was evaluated by measuring color coordinates in the CIELab color space: L* (lightness), a* (red-green), and b* (yellow-blue). The lightness values ranged between 94.21 and 95.08, and the redness values varied from −2.20 to −2.65, slightly decreasing for the films enriched with oils. In contrast, yellowness values ranged between 2.93 and 5.80 for the obtained active materials, significantly increasing compared to the control alginate film (L* = 95.48, a* = −1.92, and b* = −0.14). Changes in the structure and morphology of the alginate films after incorporating bioactive-rich oils were observed using scanning electron microscopy (SEM). Films with RSO and oil mixtures had more developed surfaces than films with BCSO. Moreover, the cross-sections of the films with RSO showed holes evenly distributed inside the films, indicating traces of volatile compounds. Thermal decomposition of the alginate films loaded with oils showed five separate stages (to 125 °C, 125–300 °C, 310–410 °C, 410–510 °C, and 750–1000 °C, respectively) related to the oil and surfactant decomposition. The shape of the thermogravimetric curves did not depend on the oil type. The added oils reduced the efficiency of alginate decomposition in the first stage. The obtained results showed that new functional and thermally stable food packaging films based on sodium alginate with a visual appearance acceptable to consumers could be produced by utilizing oils from fruit seed residues. Full article

Culinary rhubarb is grown for its large, thick leaf petioles. Red-stalked cultivars and selection are more attractive for the fresh market and processing industry. In vitro cultures are important for rapidly multiplying value genotypes and producing plants free of viruses. This study aimed to develop an in vitro propagation method for six rhubarb selections from the Raspberry (R1, R2, R3), Leader (L1, L2), and Karpow Lipskiego (KL) groups. In addition, the planting material of six rhubarb selections was subjected to phytochemical analysis using the HPLC method to assess the content of bioactive compounds. The cultures were initiated from underground buds on the crowns. The initial growth was obtained for 45 to 75% of initial explants because of bacterial contamination and low bud activity of some genotypes. The type and concentration of cytokinin and its interaction with gibberellin acid (GA₃) were shown to have a significant effect on the cyclic multiplication and commercially interesting rate of all rhubarb genotypes. A high in vitro rooting frequency, 93.7 to 95.8% for rhubarb Raspberry, 94.3 to 100% for rhubarb Leader, and 96.7% KP selections were obtained after two-cycle rooting on a medium containing IBA and NAA. The polyphenolic compounds, such as cyanidin-3-O-rutinoside, rhaponticin, resveratrol, caffeic acid, p-coumaric acid, cinnamic acid, syringic acid, and ferulic acid were detected in selected rhubarb genotypes. The highest content of anthocyanins (2.9 mg·1 g⁻¹ DM) and rhaponticin (107.8 µg·1 g⁻¹ DM) was found in Raspberry selections. On the other hand, Leader selections were characterized by the highest content of resveratrol (0.25 µg·1 g⁻¹ DM) and phenolic acids (1.3 µg·1 g⁻¹ DM). The less attractive for functional food production seems to be KL selection. Full article

Remontant raspberry cultivars originally produce fruit in the upper part of primocanes in the fall, but if retained over winter, they can produce a second crop in the lower part of the floricanes the following spring. Maintaining remontant cultivars to yield twice during the cane’s growth cycle corresponds to a double-cropping system, which enables an increase in the total yield and the extension of the fruiting season. To date, there is little information on changes in fruit quality between primocane and floricane crops. The aim of this study was, therefore, to investigate variations in the content of sugars and organic acids, fruit weight, color and textural and sensorial attributes among five newly introduced remontant raspberry cultivars (‘Dafne’, ‘Kokanee’, ‘Paris’, ‘Versailles’ and ‘Primalba’) and the control cultivar ‘Enrosadira’. The specific aim was to evaluate how a double-cropping system in each cultivar may affect the variability in quality traits between primocane and floricane crops. The results showed a significant increase in fruit weight and individual and total sugar content in primocane crops, while significantly brighter red-colored and firmer fruits were observed in floricane crops. Cultivars did not differ from the control regarding total sugar content and sweetness index, while the content of individual sugars caused greater variations. The highest content of citric, malic and total acid (9.74, 1.42 and 11.25 mg 100 g⁻¹ FW, respectively) were recorded in ‘Paris’, by which this cultivar was the only one distinguished from the control. ‘Dafne’ and ‘Versailles’ exhibited better internal and external fruit quality on primocanes, having significantly larger fruits (6.83 g and 6.37 g, respectively) and twice the increased sugar content. The lowest fruit weight was observed in ‘Kokanee’ for both primocane (4.63 g) and floricane (3.65 g) crops. ‘Kokanee’ and ‘Primalba’ also performed worse than the control for most sensory attributes in both seasons. Based on the analysis of the overall fruit quality linked to the appearance-, texture- and taste-related attributes that affect consumer preference, cultivars ‘Enrosadira’, ‘Versailles’ and ‘Dafne’ stood out, while ‘Paris’ showed high uniformity in fruit quality between crops, but scored the worst according to the total quality index. Full article

Fresh raspberries are highly perishable, but lactic acid bacteria fermentation offers a favourable method for developing healthy products. This study investigated the effects of Lacticaseibacillus paracasei fermentation on the nutrients and phytochemicals of red raspberry nectar using widely targeted metabolomics, as well as its antioxidant activity. The fermentation notably disrupted the raspberry tissue structure, reshaped its non-volatile composition, and increased its DPPH and hydroxyl free radical scavenging abilities. A total of 261 compounds showed significant differences, with 198 upregulated and 63 downregulated. Among these, certain flavonoid glucosides (e.g., pelargonid-in-3-O-rutinoside, delphinidin-3-O-rutinoside-7-O-glucoside, and kaempferol-3-O-glucoside) were significantly downregulated, while some bioactive phenolic acids (e.g., 3-(4-Hydroxyphenyl)-propionic acid and DL-3-phenyllactic acid), alkaloids (e.g., deoxymutaaspergillic acid and indole-3-lactic acid), amino acids (e.g., L-phenylalanine and L-glutamine), and B vitamins (e.g., VB6, VB7, and VB3) were substantially upregulated. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analysis revealed that metabolic pathways and the biosynthesis of secondary metabolites contributed significantly to the new profile of fermented red raspberry nectar. These findings provide valuable insights for developing fermented raspberry products using Lacticaseibacillus paracasei, which can help minimise fresh raspberry loss and enhance their valorisation. Full article

This paper presents a study on the establishment and the capitalization of a remontant red raspberry crop, the Polka variety, on a privately agricultural land area of 0.2 ha in a crop with a support system in V using a geotextile membrane for soil mulching and the method of micro-irrigation by drip. It has been shown that the annual gross profit is advantageous for diversifying the population incomes of rural areas, and the red raspberry is economically profitable regarding cultivation because the recovery of the invested sum is achieved in a maximum of 5 years after the establishment of the culture. The aim of this paper is to explore the growth and commercialization of red raspberry cultivation on privately owned arable land in rural Romania, emphasizing its potential for productivity and sustainability in the context of the circular economy. This initiative not only delivers substantial profits for investors but also fosters rural development and boosts local income levels. The study demonstrates that this cultivation method of red raspberry, aligned with the principles of the circular economy, enhances sustainability by reducing waste, optimizing resource use, and involving local communities in production cycles. Full article

Raspberry (Rubus idaeus L.) fruit are known for their extremely short shelf life. Decay, leakiness, and loss of firmness are the most common limiting factors contributing to their short storage life. However, storage in elevated CO₂ and reduced O₂ atmospheres can delay senescence in fruit by reducing softening, respiration and ethylene production rates, and pathogen growth. In this study, raspberries were exposed to four different CO₂ atmospheres—15 kPa CO₂ and 6 kPa O₂ (15 kPa); 8 kPa CO₂ and 13 kPa O₂ (8 kPa); 5 kPa CO₂ and 16 kPa O₂ (5 kPa); or 0.03 kPa CO₂ and 21 kPa O₂ (0.03 kPa)—and were evaluated for their postharvest quality periodically during two weeks of storage in 2020 and 2021. Raspberry fruits kept in a 15 kPa CO₂ atmosphere followed by 8 kPa CO₂ had higher firmness, brighter red color, and the least fungal decay or leakiness. In all atmospheres, the total anthocyanin content increased over time, although the rate of increase was slowed by high CO₂. The raspberries’ visual attributes deteriorated over time in all atmospheres, but high CO₂ atmospheres slowed the rate of deterioration. After five days, the quality of air-stored raspberries was significantly degraded, while the raspberries stored in elevated CO₂ maintained good quality for up to ten days. Full article