Search Results (42)

This study aimed to determine the stress mechanisms induced by foliar methyl jasmonate (MeJA) application in Vaccinium corymbosum cultivars subjected to water deficit (WD) and aluminum toxicity (Al). Two V. corymbosum cultivars, Star and Legacy, were subjected to different treatments in an Andisol: control (80% field capacity and low Al saturation), combined WD + Al (50% field capacity and 85% Al saturation), and different concentrations of foliar MeJA application (10 μM, 50 μM, and 100 μM) under WD + Al conditions. The determination of photosynthetic pigments, osmolytes, and organic acids, as well as the auxin levels and the expression of Aluminium-Activated Malate Transporter (ALMT) and Multidrug and Toxic Compound Extrusion (MATE) genes, was analyzed at 7 and 21 days. Foliar MeJA application increased chlorophyll a, b, and carotenoid levels, mainly at 50 µM, exhibiting early Star responses with up to 1.5-fold higher pigment accumulation, and a later increase in Legacy with up to 1.4-fold higher accumulation. Proline increases up to 2.2-fold in roots and sugar by 1.4-fold in leaves of both cultivars. The MeJA application increases the auxin levels by up to 2.3-fold in Star roots at 7 days and by up to 1.4-fold in Legacy leaves at 21 days. MeJA-induced upregulation of ALMT and MATE gene expression facilitated Al detoxification, with malate and citrate levels increasing up to 2-fold. Hierarchical clustering confirmed that the Star cultivar activated resistance mechanisms early, while the Legacy cultivar exhibited delayed but sustained resistance mechanisms. MeJA improves V. corymbosum resistance to combined WD + Al stress by modulating photosynthetic pigments, osmolytes, organic acids, and hormone regulation. This finding underscores the biotechnological potential of MeJA application to improve stress resilience and optimize crop performance under adverse environmental conditions. Full article

Vaccinium corymbosum L. ‘Biloxi’ is a cultivated blueberry variety valued for its rich content of phenolic compounds, which contribute to its strong antioxidant activity and recognized health benefits. There is little information on the effects of GA₃ and BA on blueberry, especially when used in combination. This study aimed to evaluate whether GA₃ and BA alter the yield and quality of V. corymbosum ‘Biloxi’ fruits. The experiment included 12 treatments consisting of GA₃ (25, 50 and 100 mg L⁻¹) and BA concentrations (50 and 100 mg L⁻¹) alone and combined and a control. The following parameters were analyzed: yield (g) and number of fruits per plant, mass, diameter, pH, soluble solids (SS), titratable acidity (TA), soluble sugars, total phenols, flavonoids, anthocyanins and antioxidant activity. The results indicate that foliar GA₃ and BA application improved the antioxidant capacity and biochemical composition of fruits, without negatively affecting production traits such as yield, fruit size or maturation period. The increases in antioxidant activity, phenol metabolites (total phenols, anthocyanins and flavonoids), soluble sugars, SS and SS/TA ratio were higher with the combination of GA₃ and BA at 100 mg L⁻¹. These results suggest that the combination of GA₃ and BA is a promising approach to sustainably improve fruit quality in commercial blueberry cultivation, providing both economic and nutritional benefits. Full article

Blueberry (Vaccinium corymbosum) leaves are often discarded as agricultural by-products despite their potential abundance in bioactive compounds. However, comprehensive knowledge of their phytochemical profile remains limited, especially at the cultivar level. To address this gap, this study performed untargeted metabolomic profiling of blueberry leaves from ten cultivars using UHPLC-QTOF MS. Metabolites were annotated using high-resolution mass spectrometry and MS/MS fragmentation patterns. Multivariate statistical techniques were employed to investigate inter-cultivar variability and identify distinctive metabolites. A total of 76 metabolites were discovered, with 64 being confidently annotated and grouped into ten main phytochemical classes. The relative abundances of phenolic acids, flavonols, and flavan-3-ols varied significantly among cultivars. Several metabolites were annotated for the first time in V. corymbosum leaves, such as miscanthoside, glucoliquiritin, apiin, khelloside, and aromadendrin. These metabolites are known in other plants for their biological activities, demonstrating blueberry leaves’ bioactive potential. This study highlights the importance of untargeted metabolomic approaches in elucidating the biochemical diversity of plant matrices. The metabolomic data revealed significant cultivar-specific variations and novel bioactive metabolite annotation. These findings establish a complete phytochemical fingerprint for each cultivar, providing a basis for future research to validate key metabolites’ biological activities and support the valorisation of V. corymbosum leaves. Full article

Agraz (Vaccinium meridionale Swartz) is a shrub native to the Neotropical region of South America, including Colombia, Ecuador, Venezuela, and Peru. Known for its edible fruits valued for their nutritional, nutraceutical, and medicinal properties, the species remains underexplored despite its potential. This research aimed to investigate the genetic diversity and population structure of agraz in Colombia, focusing on native individuals from Santander and commercial individuals from Boyacá and Cundinamarca, providing insights that can support conservation and genetic improvement efforts. Methods: In this study, genotyping by sequencing (GBS) was used to analyze genetic variation and population structure in V. meridionale. The sequencing data were aligned to the V. corymbosum cv. Draper v1.0 reference genome. The obtained single-nucleotide polymorphisms (SNPs) were employed to evaluate genetic diversity, population differentiation, and inbreeding coefficients, with measures such as expected heterozygosity and F-statistics providing insights into population structure and genetic composition across regions. Results: A total of 12,910 SNPs were obtained, and the results revealed moderate genetic diversity within the agraz populations, characterized by an expected heterozygosity (He) of 0.3586. A negative Fis value indicated an excess of heterozygosity and low genetic differentiation among the sampled regions. Population structure analysis identified three distinct subpopulations, with Subpopulation 3 exhibiting the most unique genetic composition. Conclusions: This study provides the first genetic diversity analysis of V. meridionale in Colombia using the GBS approach. The findings contribute to the understanding of the species’ genetic variability and offer valuable information for conservation strategies, genetic improvement and breeding programs to enhance its agricultural potential and ensure the sustainable utilization of agraz resources. Full article

Dihydroflavonol 4-reductase (DFR) genes contribute greatly to anthocyanin biosynthesis in plants. Up to now, however, research on the DFR gene family and the key anthocyanin-related DFR members in blueberries (Vaccinium corymbosum) has been limited. In this study, we performed a genome-wide identification of the blueberry DFR gene family, identifying 36 VcDFR genes categorized into five subfamilies. Gene expression analysis showed that three Subfamily III members (VcDFR11/29/34) and four Subfamily V members (VcDFR4/7/30/33) are highly expressed in blueberry fruits, particularly at late ripening stages. Transient overexpression analysis in apple fruits verified the contributions of VcDFR11 and VcDFR30 to anthocyanin biosynthesis, with VcDFR11 showing better promoting effects. Blueberry fruit-based transient overexpression further confirmed the promoting effects of VcDFR11 on anthocyanin accumulation and the expression of anthocyanin-related structural genes (especially its downstream anthocyanindin synthase (ANS) and UDP-glucose: flavonoid 3-O-glycosyltransferase (UFGT) genes). The VcDFR11 promoter contains binding sites for both bHLH and MYB transcription factors (TFs). Consistently, yeast one-hybrid and dual-luciferase assays confirmed that anthocyanin-related VcMYB-1 and VcbHLHs can bind to and activate the VcDFR11 promoter. Furthermore, co-overexpressing VcMYB-1/VcbHLHs with VcDFR11 led to much higher anthocyanin accumulation than overexpressing VcDFR11 alone, indicating that these TFs positively regulate anthocyanin biosynthesis by upregulating VcDFR11. In summary, our study characterized the blueberry DFR gene family and demonstrated the role of VcDFR11 in anthocyanin biosynthesis. Full article

Vaccinium corymbosum is one of the main sources of commercialized blueberries across the world. This species has a large number of distinct cultivars, leading to significantly different berries characteristics such as size, sweetness, production rate, and growing season. In this context, accurate cultivar discrimination is of significant relevance, and currently, it is mostly performed through berries examination. In this work, we developed a method to discriminate 19 cultivars from the V. corymbosum species through their leaves’ near-infrared spectra. Spectra were acquired from fresh blueberry leaves collected from two geographic regions and across three seasons. Machine-learning-based models, selected from a pool of 10 classifiers based on their discrimination power under a twofold stratified cross-validation process, were trained/tested with 1 to 20 components obtained by the application of data dimensionality reduction (DDR) techniques (dictionary learning, factor analysis, fast individual component analysis, and principal component analysis) to different near-infrared (NIR) spectra regions’ data, to either analyze a single spectral region and season or combine spectral regions and/or seasons for each side of the blueberry leaf. The percentage of correct cultivar discrimination ranged from 52.27 to 100%, with the best spectral results obtained with the adaxial side of the leaves in the fall (100% $Accuracy$) and the abaxial side of the leaves in the winter (100% $Accuracy$); the fast ICA DDR technique was present in 83.33% of the best analyses (five out of six); and the LinearSVC was present in 66.67% (four out six best analyses). The results obtained in this work denote that near-infrared spectroscopy is a suitable and accurate technique for V. corymbosum cultivar discrimination. Full article

Hyperhydricity is a significant challenge in the tissue culture of blueberry plantlets, affecting their propagation, survival and quality, which results in economic losses for industrial blueberry micropropagation. The in vitro liquid propagation of two half-highbush blueberry hybrids, HB₁ and HB₂, showed that a Growtek stationary bioreactor culture system containing a liquid medium exhibited a higher hyperhydricity percentage than a Sigma glass culture system with a semi-solid medium. The percentage of hyperhydricity (75.21 ± 1.89%) and water content (72%) of HB₂ was more than that of HB₁. A scanning electron microscopy study revealed that hyperhydric plantlets from both genotypes developed slowly, had closed stomata, and displayed enlarged intercellular spaces between the palisade and spongy parenchyma layers. Disrupted vascular bundles, underdeveloped sieve elements and a weak connection between phloem and xylem tissue were also observed in hyperhydric plantlets. An analysis of mesophyll and stem tissues highlighted a compressed adaxial epidermis, which led to compact palisade parenchyma, with irregularly shaped mesophyll cells. Hyperhydric plants showed strong nuclear magnetic resonance (NMR) signals in the aliphatic, aromatic, and sugar regions, specifically at peaks of 2.0, 2.5, 4.0, 4.5, 6.0, and 6.7 ppm. These signals were attributed to the presence of catechin (C₁₅H₁₄O₆), a flavonoid compound, suggesting its significant role or accumulation in these plants under hyperhydric conditions. Despite the negative effects of hyperhydricity on commercial propagation, hyperhydric plants were found to contain higher levels of valuable untargeted metabolites, such as β-P-arbutin, chlorogenic acid, quercetin-3-O-glucoside, epicatechin, 2-O-caffeoyl arbutin, various fatty acids, β-glucose, linolenic acid, and acetyl than both in vitro and ex vitro conditions. The enrichment of bioactive compounds in blueberry enhances its antioxidant properties, nutritional profile, and potential health benefits, making them significant for plant defense mechanisms and stress adaptation. Full article

This work focuses on the green synthesis of zinc oxide nanoparticles (ZnO NPs) to be used as a photocatalyst, preparing a blueberry (Vaccinium corymbosum) extract as a reducing agent, zinc chloride as a precursor, and NaOH as precipitating agent (1, 7 and 14 M). Characterization techniques included X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis), Fourier-transform infrared (FTIR), X-ray photoelectron (XPS), and Raman spectroscopy. The XRD analysis confirmed the hexagonal wurtzite crystalline structure of ZnO NPs, while the SEM and TEM revealed a flower-like morphology. Moreover, the ZnO NPs exhibited a band gap energy in the range of 3.17 to 3.27 eV, depending on the concentration of NaOH. Regarding the photocatalytic activity, the synthesized ZnO NPs showed a photocatalytic efficiency greater than 90%, degrading malachite green (MG) dye in 60 min under sunlight. The proposed photocatalytic mechanism includes reactive oxygen species (ROS) generation (hydroxyl radicals (OH^•) and superoxide radicals (O²⁻)). The XRD and Raman analysis also revealed that the ZnO NPs maintained structural integrity after repeated photocatalytic cycles, emphasizing their stability and suitability for practical applications. Full article

The Vaccinium genus contains about 500 species distributed worldwide but only a limited number of species have been studied for genetic diversity using molecular markers. In this study, a genetic analysis was conducted on three Vaccinium species (four cultivars of V. corymbosum, four wild populations of V. myrtillus, and two cultivars of V. ashei), for a total of 95 genotypes, using eight microsatellite (SSR) loci. A total of 57 alleles were detected. The number of alleles per locus ranged from 2 to 14, with an average of 7.25. Six unique alleles in V. corymbosum, four in V. ashei, and three in V. myrtillus were identified as being potential species markers. The dendrogram and principal coordinate analysis revealed a clear division of the three species into distinct groups, with each group further divided into sub-clusters based on the type of cultivars and population origin. The set of SSR primers used in this study demonstrated cross-species transferability, allowing their utilization in V. ashei and V. myrtillus, and can be used as a reliable tool for cultivar/population and species identification in blueberries. Full article

In this work, cultures of callus and suspension cells originating from leaves of sterile highbush blueberry (Vaccinium corymbosum L.) plants were obtained and characterized. For their active growth and production of phenolic compounds, a combination of 2,4-D at a concentration of 0.34–2.25 µM and BAP at a concentration of 0.45–2.25 µM is effective. An increase in the phytohormone concentration leads to a slowdown in culture formation and reduces their ability to synthesize phenolic compounds. When cultivating V. corymbosum suspension cells over a year (12 passages), they not only retain the ability to synthesize phenolic compounds but also enhance it. By the 12th passage, the content of TSPC in suspension cells reaches 150 mg/g DW, the content of flavonoids reaches 100 mg/g DW, the content of flavans reaches 40 mg/g DW, and the content of proanthocyanidins reaches 30 mg/g DW. The high content of phenolic compounds may be due to the high expression of genes in flavonoid biosynthesis enzymes. V. corymbosum suspension cells accumulate a high level of phenolic compounds during a passage. The ability of V. corymbosum callus and cell suspension cultures in the presence of low concentrations of phytohormones to grow and accumulate biologically active phenolic compounds determines their high economic significance and prospects for organizing a biotechnological method for obtaining phenolic compounds. Full article

Due to climate change, water deficits (WDs) and aluminum (Al) toxicity are increasing, affecting plants, especially crops such as blueberries (Vaccinium corymbosum L.). The application of methyl jasmonate (MeJA) could mitigate these effects. This work aimed to evaluate the effective MeJA dose to overcome oxidative stress provoked by combined WD+Al stress in blueberries. Plants of Al-sensitive (Star) and Al-resistant (Legacy) cultivars were exposed to control (Al at 65 mg/Kg, 80% field capacity), WD+Al (50% field capacity; Al at 1665 mg/Kg), and WD+Al treatment with different foliar MeJA doses (10, 50, and 100 μM) during 7 and 21 days. Data revealed that plants exposed to WD+Al and treated with 50 µM MeJA reduced Al up to 3.2-fold in roots and 2.7-fold in leaves and improved water potential (Ψw) up to 2.5-fold. The sensitive cultivar decreased the relative growth rate under WD+Al, increasing by 1.9-fold with 50 µM MeJA. Under WD+Al stress, all MeJA doses mitigated the decrease in relative water content in Al-resistant cultivars, restoring values like control plants. In the sensitive cultivar, 50 µM MeJA increased photosynthesis (1.5-fold) and stomatal conductance (1.4-fold), without changes in transpiration. Lipid peroxidation decreased (1.2-fold) and increased antioxidant activity (1.8-fold), total phenols (1.6-fold), and superoxide dismutase activity (3.3-fold) under WD+Al and 50 µM-MeJA. It was concluded that the most effective dose to alleviate the WD+Al stress was 50 µM MeJA due to the activation of antioxidants in blueberry plants. Therefore, the MeJA application could be a potential strategy for enhancing the resilience of V. corynbosum exposed to WD+Al stress. Full article

In this study, the physiological performance and fruit quality responses of the highbush blueberry (Vaccinium corymbosum) cultivar Legacy to high temperatures (HTs) were evaluated in a field experiment. Three-year-old V. corymbosum plants were exposed to two temperature treatments between fruit load set and harvest during the 2022/2023 season: (i) ambient temperature (AT) and (ii) high temperature (HT) (5 °C ± 1 °C above ambient temperature). A chamber covered with transparent polyethylene (100 µm thick) was used to apply the HT treatment. In our study, the diurnal temperature was maintained with a difference of 5.03 °C ± 0.12 °C between the AT and HT treatments. Our findings indicated that HT significantly decreased CO₂ assimilation (P_n) by 45% and stomatal conductance (g_s) by 35.2% compared to the AT treatment. By contrast, the intercellular CO₂ concentration (Ci) showed higher levels (about 6%) in HT plants than in AT plants. Fruit quality analyses revealed that the fruit weight and equatorial diameter decreased by 39% and 13%, respectively, in the HT treatment compared to the AT treatment. By contrast, the firmness and total soluble solids (TSS) were higher in the HT treatment than in the AT treatment. Meanwhile, the titratable acidity showed no changes between temperature treatments. In our study, P_n reduction could be associated with stomatal and non-stomatal limitations under HT treatment. Although these findings improve our understanding of the impact of HTs on fruit growth and quality in V. corymbosum, further biochemical and molecular studies are need. Full article

To further clarify the impact of different rootstocks in grafted blueberry, fruit quality, mineral contents, and leaf gas exchange were investigated in ‘O’Neal’ blueberry (Vaccinium corymbosum) grafted onto ‘Anna’ (V. corymbosum) (AO), ‘Sharpblue’ (V. corymbosum) (SO), ‘Baldwin’ (V. virgatum) (BO), ‘Plolific’ (V. virgatum) (PO), and ‘Tifblue’ (V. virgatum) (TO) rootstocks and own-rooted ‘O’Neal’ (NO), and differences in anatomic structures and drought resistance were determined in AO, TO, and NO. The findings revealed that fruit quality in TO and PO was excellent, that of BO and SO was good, and that of AO and NO was medium. ‘Tifblue’ and ‘Plolific’ rootstocks significantly increased the levels of leaf phosphorus and net photosynthetic rate of ‘O’Neal’, accompanied by a synchronous increase in their transpiration rates, stomatal conductance, and intercellular CO₂. Additionally, the comprehensive evaluation scores from a principal component analysis based on anatomic structure traits from high to low were in the order TO > AO > NO. The P₅₀ (xylem water potential at 50% loss of hydraulic conductivity) values of these grafted plants descended in the order NO > AO > TO, and the branch hydraulic conductivity of TO and sapwood hydraulic conductivity of TO and AO were significantly lower than those of NO. Thus, TO plants exhibited the strongest drought resistance, followed by AO, and NO, and this trait was related to the effects of different rootstocks on the fruit quality of ‘O’Neal’ blueberry. These results provided a basis for a deeper understanding of the interaction between rootstocks and scions, as well mechanisms to improve blueberry fruit quality. Full article

Since its domestication about a century ago in North America, highbush blueberry (Vaccinium corymbosum L.) has gained appreciation by consumers worldwide, and the demand for new blueberry varieties is increasing. Whole-genome resequencing can help plant breeders to decrease the time needed to create novel varieties by identifying novel genes linked to fruit-quality traits. The present study analyzed the genetic variability of eight V. corymbosum genotypes, seven Romanian varieties (‘Prod’, ‘Vital’, ‘Azur’, ‘Simultan’, ‘Delicia’, ‘Compact’, and ‘Safir’), and the American variety, ‘Bluecrop’. The analysis of the first ~10 Mb from scaffold 22, a hotspot of genomic variation, in the above-mentioned varieties revealed multiple differences in 11 upregulated and 50 downregulated genes involved in fruit growth and development. Of these differentially regulated genes, two upregulated and five downregulated genes were fully covered by at least 1× coverage depth by sequencing. The genes’ sequence analysis confirmed the high genetic variability of the region, with most of the genes presenting numerous SNPs and some InDels, and indicated that an attempted 10× medium-coverage depth of sequencing for V. corymbosum varieties yields useful preliminary data for use in breeding programs. Full article

Photoaging is a process related to an increased level of reactive oxygen species (ROS). Polyphenols can scavenge free radicals in the body, which can delay skin aging. Therefore, our work aimed to prepare a biologically active extract from dry fruits of Vaccinium myrtillus or Vaccinium corymbosum and use it for the preparation of hydrogels for topical application. Therefore, eight different extracts (using V. myrtillus and V. corymbosum and different extraction mixtures: methanol, methanol–water 1:1, water, acetone–water 1:1) were prepared and their phytochemical (total polyphenolic content, total flavonoid content, total anthocyanin content) and biological properties (antioxidant, anti-hyaluronidase, and anti-tyrosinase activity) were assessed. Cytotoxicity towards HaCaT keratinocytes was also determined. Based on the results, the acetone–water extract from V. myrtillus was selected for further study. Using the Design of Experiments approach, chitosan-based hydrogels with bilberry fruit extract were prepared. The content of extract and chitosan were selected as independent factors. The activity of hydrogels depended on the extract content; however, the enzyme-inhibiting (anti-hyaluronidase and anti-tyrosinase) activity resulted from the presence of both the extract and chitosan. Increased concentration of chitosan in the hydrogel base led to increased viscosity of the hydrogel and, consequently, a slower release of active compounds. To get optimal hydrogel characteristics, 1% extract and 2.5% MMW chitosan were utilized. The research suggests the validity of using bilberry fruit extracts in topical preparations with anti-aging properties. Full article