Search Results (130)

Strawberries (Fragaria x ananassa Duch.) are highly perishable fruits that rapidly lose their quality properties, even when stored under cold conditions. The purpose of this research was to study the effectiveness of hesperidin (10, 50, and 100 mg L⁻¹) to preserve harvest-ripe strawberry quality during cold storage (2 °C). The data obtained indicate that hesperidin treatments were able to delay fruit metabolism and thus weight loss, while maintaining firmness and delaying colour evolution, obtaining positive results even with the lower concentrations applied. Strawberries treated with hesperidin exhibited a cell membrane with greater integrity, as reflected by a lower loss of electrolytes, resulting from reduced oxidation degradation. In addition, these strawberries maintained a higher concentration of chlorophylls in the calyx during storage, which could be due to a better antioxidant balance and a more effective preservation of their qualities. In this regard, the levels of bioactive substances, including total phenolics and the major anthocyanin compounds present in strawberries, were delayed in hesperidin-treated strawberries. This is the first report highlighting the effectiveness of hesperidin as a postharvest treatment in fruit, specifically in strawberries, delaying senescence. These results suggest that hesperidin, either by itself or in hesperidin-rich extracts, could become a valuable tool for postharvest fruit preservation. Full article

The commercial propagation of strawberries is increasingly constrained by the incidence of both established and emerging soilborne pathogens, particularly under soil cultivation systems. Micropropagation represents an effective strategy to ensure the production of virus-free, true-to-type mother plants suitable for high-efficiency propagation. In this study, micropropagated mother plants of four short-day cultivars (‘Francesca’, ‘Silvia’, ‘Lauretta’, and ‘Dina’) and one ever-bearing advanced selection (‘AN12,13,58’) were cultivated under a controlled soilless system. Quantitative parameters including number of runners per plant, runner length, and number of tips per runner and per plant were assessed to evaluate propagation performance. Micropropagated mother plants exhibited a significantly higher stoloniferous potential compared to in vivo-derived mother plants (frigo plants type A), with the latter producing approximately 50% fewer propagules. Rooted tips of ‘Dina’ were further assessed under different fertigation regimes. The NPK 20–20–20 nutrient solution enhanced photosynthetic activity and shoot and root biomass (length, diameter, and volume via WinRHIZO analysis). These results confirm the suitability of micropropagated mother plants grown in soilless conditions for efficient, high-quality clonal propagation and support the integration of such systems into certified nursery production schemes. Full article

Tetranychus urticae, commonly known as the two-spotted spider mite, is a highly adaptable and polyphagous arthropod in the family Tetranychidae, capable of feeding on over 1200 plant species, including strawberries (Fragaria × ananassa Duch.). The fitness and microbiota of herbivorous arthropods can vary significantly across different plant species and cultivars. In this study, we investigated the fecundity, longevity, growth rate, and microbiota composition of T. urticae reared on seven Chinese strawberry cultivars: Hongyan (HY), Yuexiu (YX), Tianshi (TS), Ningyu (NY), Xuetu (XT), Zhangjj (ZJ), and Xuelixiang (XLX). Our findings revealed significant differences among cultivars: mites reared on the XT cultivar exhibited the highest fecundity (166.56 ± 7.82 eggs), while those on XLX had the shortest pre-adult period (7.71 ± 0.13 days). Longevity was significantly extended in mites reared on XLX, XT, and NY cultivars (25.95–26.83 days). Microbiota analysis via 16S rRNA sequencing showed that Proteobacteria dominated (>89.96% abundance) across all mite groups, with Wolbachia as the predominant symbiont (89.58–99.19%). Male mites exhibited higher bacterial diversity (Shannon and Chao1 indices) than females, though Wolbachia abundance did not differ significantly between sexes or cultivars. Functional predictions highlighted roles of microbiota in biosynthesis, detoxification, and energy metabolism. These findings underscore the influence of host plant variety on T. urticae fitness and microbiota composition, suggesting potential strategies for breeding resistant strawberry cultivars and leveraging microbial interactions for pest management. Full article

Potassium is the most abundant macronutrient in plants, participating in essential physiological processes such as turgor maintenance. A reduction in cell turgor is a hallmark of the ripening process associated with fruit softening. The dynamic of K⁺ fluxes in fleshy fruits is largely unknown; however, the reallocation of K⁺ into the apoplast has been proposed as a contributing factor to the decrease in fruit turgor, contributing to fruit softening. High-affinity K⁺ transporters belonging to the KUP/HT/HAK transporter family have been implicated in this process in some fruits. In this study, a comprehensive genome-wide analysis of the KUP/KT/HAK family of high-affinity K⁺ transporters in strawberry (Fragaria × ananassa Duch.) was conducted, identifying 60 putative transporter genes. The chromosomal distribution of the FaKUP gene family and phylogenetic relationship and structure of predicted proteins were thoroughly examined. Transcriptomic profiling revealed the expression of 19 FaKUP genes within the fruit receptacle, with a predominant downregulation observed during ripening, particularly in FaKUP14, 24 and 47. This pattern suggests their functional relevance in early fruit development and turgor maintenance. Mineral composition analyses confirmed that K⁺ is the most abundant macronutrient in strawberry fruits, exhibiting a slight decrease as ripening progressed. Membrane potential (E_m) and diffusion potentials (E_D) at increasing external K⁺ concentrations were measured by electrophysiology in parenchymal cells of green and white fruits. The results obtained suggest a significant diminution in cytosolic K⁺ levels in white compared to green fruits. Furthermore, the slope of change in E_D at increasing external K⁺ concentration indicated a lower K⁺ permeability of the plasma membrane in white fruits, aligning with transcriptomic data. This study provides critical insights into the regulatory mechanisms of K⁺ transport during strawberry ripening and identifies potential targets for genetic modifications aimed at enhancing fruit firmness and shelf life. Full article

Strawberry (Fragaria × ananassa Duch.) is an important fruit worldwide whose growth, development, and productivity are threatened by salinity. The WRKY transcription factors (TFs) were reported to play an important role in regulating abiotic stresses response. However, research on their roles to regulate salt stress tolerance in strawberry remains limited. In current study, the FvWRKY75 gene was isolated and characterized from the Ruegen strawberry, and induced by various stress treatment. The results showed that the FvWRKY75 transcription factor was a transcriptional activator and localized in the nucleus. Phenotypic and physiological analysis revealed that ectopic expression of FvWRKY75 in Arabidopsis improved salt tolerance by enhancing the antioxidant system activities, modulating ROS scavenging and upregulating stress-related genes. Y1H and dual luciferase assays revealed that FvWRKY75 can directly bind to the promoter of the FvCRK5 gene by recognizing the W-box element. Compared with the WT, ectopic expression of FvCRK5 gene in Arabidopsis enhanced salt tolerance characterized by the reduced ROS accumulation, higher chlorophyll content, lower MDA content, and enhanced SOD and POD activity. Herein, the FvWRKY75 gene acted as a positive regulator in salt stress resistance, at least in part, via the WRKY-CRK network to regulate the antioxidant enzyme defense system and stress-related genes to regulate salt stress tolerance in strawberry. Full article

To study the effects of different microbial agents on the microbial community structure of continuously cropped strawberry soil after soil fumigation, seven treatments were applied: T1 (Trichoderma harzianum + Bacillus subtilis + actinomycetes), T2 (Trichoderma harzianum + Bacillus subtilis), T3 (Trichoderma harzianum + actinomycetes), T4 (CK) (water control), T5 (Bacillus subtilis), T6 (actinomycetes) and T7 (Trichoderma harzianum). A high-throughput sequencing platform (Illumina HiSeq 2500) was used to analyze the soil bacterial and fungal communities and their compositions. Compared with the T4 (CK) treatment, the application of microbial agents increased the richness and diversity of soil bacteria and fungi, and the effects of single microbial agents and compound microbial agents differed. The richness, diversity indices and population sizes of bacteria and fungi in the T6 treatment were the highest. The Chao1, observed species and Shannon indices of bacteria were 22.51%, 23.56% and 5.61% greater, respectively, than those of T4 (CK). The Chao1, observed species, Shannon and Simpson indices of fungi were 41.28%, 41.83%, 128.02% and 88.65% higher, respectively, than those of T4 (CK). At the genus level, the bacterial community compositions of T2 and T6 were the most similar, and the fungal community compositions of T1 and T5 were the most similar. Analysis of the genera in the dominant communities revealed that the application of microbial agents after dazomet fumigation increased the numbers and recovery rates of soil bacteria and fungi, especially the beneficial fungal genera, Lecanicillium, Cladosporium, Saccharomyces and Aspergillus. An investigation of strawberry growth and yield-related indicators revealed that the T6 treatment resulted in the lowest seedling mortality and the highest yield. In summary, adding microbial agents to soil with continuous cropping of strawberry after fumigation with dazomet is a scientifically sound and effective method for reconstructing the balance of the soil microbial flora and overcoming the obstacles associated with continuous cropping. In this study, the T6 (actinomycetes) treatment presented the best performance. Full article

Strawberries (Fragaria x ananassa Duch.) are highly perishable fruits with a short postharvest shelf life, requiring effective preservation techniques. This study evaluates the efficacy of γ-aminobutyric acid (GABA) and 1-methylcyclopropene (1-MCP) in maintaining strawberry quality during cold storage. Freshly harvested strawberries were treated with different concentrations of GABA (1–20 mM), and a commercial 1-MCP concentration was suggested for strawberries (250 nL L⁻¹) before being stored at 2 °C for up to 12 days. Different quality, physiological, and biochemical parameters were evaluated every 3 days after harvest. Results showed that both GABA and 1-MCP treatments effectively delayed fruit senescence. GABA demonstrated a higher effect on reducing weight loss, around 35.01% and 5.29% for 10 mM GABA and 1-MCP, respectively, compared to control fruit after 12 days at 2 °C. These substances also were effective in preserving firmness, but better maintenance was observed for 10 mM GABA than for 1-MCP (5.11 ± 0.43 and 3.49 ± 0.37 N, respectively) compared with control fruit after 12 days at 2 °C (2.56 ± 0.46 N). On the other hand, lower GABA concentrations (1–5 mM) and 1-MCP were particularly effective in delaying colour evolution and maintaining cell membranes and bioactive compounds such as polyphenols. In conclusion, as a postharvest treatment, GABA potentially offers an alternative or complement to 1-MCP in prolonging strawberry storability. These findings could contribute to developing sustainable strategies to reduce postharvest losses and improve strawberry marketability. Full article

Non-chemical methods of fertilisation and protection have been gaining importance in recent years. This trend is closely linked to current European Union (EU) agricultural policy and the growing consumer awareness of the impact of nutrition on health. Newly developed biopreparations have to be tested for their agricultural efficiency alongside a quality assessment of the resulting food. The aim of this study was to determine whether the use of newly developed microbially enriched fertilisers in organic strawberry cultivation had an effect on fruit chemical composition and heavy metal accumulation. In the research, five biopreparations (K2–K6 combinations) containing selected Bacillus strains and plant extracts were tested in 2021 and 2022 on three strawberry cultivars: ‘Honeoye’, ‘Rumba’, and ‘Vibrant’. After the vegetation period, the collected fruit samples were frozen, freeze-dried, and subjected to chemical analyses to determine the total carbon and nitrogen content, as well as the concentration of microelements (Mn, Fe), macroelements (Na, Mg, K, Ca, P) and heavy metals (Cd, Pb, Cu, and Zn). The application of the tested biopreparations did not significantly impact the total carbon content of strawberry fruit. For most of the tested traits, cultivars reacted differently to the tested preparations. A higher total nitrogen content was found for treatments treated with biopreparations, especially for the ‘Vibrant’ cultivar—ranging from 15.2 g·kg⁻¹ K2 (BacilRoots) to 16.3 g·kg⁻¹ K3 (BacilRoots + BacilExtra) and K5 (BacilRoots + BacilExtra + BacilHumus)—being about 10–18% higher than on the control object (K1). The content of sodium, phosphorus, calcium, and magnesium did not change significantly under the influence of biopreparations. The use of the K3 and K5 treatment resulted in significantly lower iron contents when compared to those of the control (strawberries sprayed with water with no biopreparations added)—respectively, by 16.1% and 17.9%. ‘Vibrant’ treated with water (control treatment) showed the highest contents of iron, copper, and zinc when compared to those treated with biopreparations. No exceedances of the permissible heavy metal content were found in the samples tested. Full article

Scientific management and environmental regulation of facility strawberries depends on the level of accurate prediction and forecasting of low temperature freezes in plastic greenhouses during winter and spring strawberry cultivation. Accurate identification of potential factors affecting layer-by-layer minimum temperatures in plastic greenhouses and selection of optimal forecasting methods are important for safe strawberry production. However, the identification of important drivers of minimum temperatures in plastic greenhouses and the prediction of potential drivers of use are still unclear. In this study, we used Classification and Regression Tree (CART) to identify the importance of the potential factors affecting the minimum temperatures at different depths and different heights of plastic greenhouses. Random forest (RF), back-propagation (BP), and multiple linear regression (MLR) were used to establish the minimum temperature prediction models for plastic greenhouses at different depths and heights, respectively. The results showed that T_smin10, T_smin25, T_amin150, T_amin320, and T_amin150 were the most important variables explaining the changes in minimum temperatures at heights T_smin25, T_smin10, T_smin2, T_amin150, and T_amin320 respectively. RF, BP performed much better than MLR, as it showed much lower error indices (AE and RMSE) and higher R² than MLR. The superiority of RF and BP in predicting minimum temperatures is related to their ability to deal with non-linear and hierarchical relationships between minimum temperatures and predictors. The low-temperature frost protection and fine management of strawberries in the Changfeng area can be related to the prediction method of minimum temperature in plastic greenhouses constructed in this study. Full article

Light quality is a fundamental factor in greenhouses, since different light wavelengths affect plant photosynthesis and photomorphogenesis differently, they thus affect crop growth and productivity. The aim of this study was to evaluate the effect of an experimental greenhouse cover film with UV-to-Red spectral shifting properties on photosynthesis, plant growth, fruit yield, and the quality of two crops spanning over a year-long cultural cycle: aubergines (Solanum melongena L.), as a spring–summer crop, followed by strawberries (Fragaria × ananassa Duch.), as an autumn–spring crop. Trials were carried out in a multispan greenhouse where two sectors were covered, each one with a different light diffusing polyethylene film: one sector was covered with a UV-to-Red photoluminescent film, doped with a blend of rare-earth elements partially converting the UV solar radiation into Red wavelengths, while a light diffusing polyethylene film was used as the control. At the physiological level, spectral shifting affected the chlorophyll fluorescence parameters related to the photochemistry of photosynthesis, which were found to be positively related to crop yield. Moreover, differential analysis of the fast Chlorophyll a fluorescence transients (or OJIP kinetics) showed that spectral shifting affected different steps of the plant photochemical metabolism. Full article

Organic farming is an environmentally friendly management practice that excludes the use of synthetic inputs, but at the same time is associated with lower yields than conventional production. In an attempt to compensate for yield reduction, resulting from foregoing the use of synthetic fertilizers, we hypothesized that the use of biostimulant products could provide much-desired food security. In light of this, a greenhouse experiment was conducted to compare and evaluate the effects of the foliar application of three different non-microbial biostimulants (a seaweed extract, a plant protein hydrolysate, and a plant extract) on the yield, mineral profile, and physiological response of strawberry (Fragaria × ananassa Duch.) grown in an organic farming context. Regardless of the type of biostimulant, treated plants showed significant improvement in photosynthetic performance. Specifically, the application of plant-derived protein hydrolysate increased ACO₂ by 34.5% compared with control. Despite this, only the application of plant-derived protein hydrolysate significantly increased fruit yield per unit area (+13.5%). The improved performance of plants treated with plant-derived protein hydrolysate was associated with an overall improvement in mineral profile (compared to control +49.4 and 33.0% in NO₃⁻ and Mg²⁺ concentration, respectively). In contrast, application of the seaweed biostimulant increased (+17.4%) fruit antioxidant activity (DPPH) compared with control plants. These results underscore how the diverse origins of non-microbial biostimulants are responsible for specific responses in crops that can be exploited by organic growers to increase productivity. Full article

Research was conducted to examine the marketable yield and fruit weight of six strawberry cultivars (Fragaria × ananassa Duch. ‘Festival’, ‘Fortuna’, ‘Brilliance’, ‘Red Rhapsody’, ‘Sundrench’ and ‘Suzie’) over two years in subtropical Queensland, Australia. In the first year, the transplants were planted on 30 March, while in the second year, they were planted on 22 April. The average daily minimum temperature was 3 °C higher than the long-term average for the area from 1965 to 1990, while the average daily maximum temperature was 1 °C higher. Temperatures and solar radiation were similar in the two years of the study. In contrast, it was wetter in the second year (478 mm) than in the first year (332 mm). Average yield was lower in the second year (142 ± 10 g/plant) than in the first year (330 ± 9 g/plant) (p < 0.001), possibly due to a later planting. Higher rainfall in the second year may have also contributed to a higher incidence of rain damage and fruit rots. Yield was lower in ‘Sundrench’ (176 g/plant) than in the other cultivars (235 to 252 g/plant) (p = 0.003). Fruit weight was lower in the second year (18.2 g) than in the first year (23.8 g) (p < 0.001), and lower in ‘Festival’ and ‘Fortuna’ (18.2 and 19.4 g), intermediate in ‘Brilliance’, ‘Red Rhapsody’ and ‘Sundrench’ (21.0, 21.3 and 21.8 g) and higher in ‘Suzie’ (24.3 g) (p < 0.001). These results demonstrate that yield and fruit size vary in cultivars in Queensland. ‘Suzie’ had the largest fruit, favoring marketing. The low productivity of ‘Sundrench’ suggests that this cultivar is not commercially viable in Queensland. Yields are expected to decline in the future under global warming, in the absence of better-adapted cultivars and other mitigating strategies. Further evaluations of cultivars in Queensland are required under different growing practices, including earlier times of planting, higher plant densities, light shade and protected cropping. Full article

Plant biostimulants have been the subject of intense interest in recent years. The aim of this study was to assess, during the years 2021–2022, the effect of mineral nitrogen (N) fertilizer, experimental (PGPB) and commercial (G) microbial biostimulants, and humic substance product (A) on the soil microbial communities, and yield of strawberries, under field conditions. Dehydrogenase activity was significantly affected by nitrogen fertilization, but an increase occurred in the treatment N+G. The treatments N+G, N+G+A, and N+PGPB+A increased FDA hydrolysis, and phosphatase activity. All plant biostimulants increased basal as well as substrate-induced respiration. Culturable bacteria (total counts, dormant forms, actinomycetes) were not clearly affected by treatment. Based on 16S rRNA analysis, bacterial community composition was different in N+PGPB+A and N+G+A treatments. The number of cultivable fungi was significantly lower in N+PGPB and N+PGPB+A treatments. The genus of fungi Pilidium, a potential phytopathogen of strawberries, was present in the second year, but in these treatments, it was absent. In the second year, strawberry yield was shown to be 95% higher in the N+PGPB+A treatment than in the control. Microbial biostimulants in combination with humic substances represent a potential solution in increasing strawberry production. Full article

Water scarcity is an ecological issue affecting over 10% of Europe. It is intensified by rising temperatures, leading to greater evaporation and reduced precipitation. Agriculture has been confirmed as the sector accounting for the highest water consumption globally, and it faces significant challenges relating to drought, impacting crop yields and food security. Sustainable practices, precision irrigation, and the development of drought-resistant crops are essential for the mitigation of this threat. Effective, innovative solutions are crucial for optimizing water use for intensive crops such as cultivated strawberries (Fragaria × ananassa). This study emphasizes the importance of identifying the genotypes most resilient to low water availability. Experimental trials involving reduced irrigation levels were set up to identify genotypes with a greater capacity to increase fruit quality and maintain fruit yield. Reduced water conditions positively influenced strawberry fruit quality, exhibiting improved citric acid, soluble solids, and color brightness linked to decreased water use, while firmness remained stable. Notably, the total phenolic content was most affected by stress, indicating strong antioxidant responses. With these interesting variations in fruit quality came a different response in plant yield. Plants belonging to the Lauretta and AN15,07,53 cultivars maintained a 98% fruit yield when grown under WS1 conditions. While the yield for the Francesca cultivar increased by 10% under the stressed WS1 conditions in comparison to the control conditions, water stress in the WS2 treatment caused a strong reduction in yield in all three genotypes. Overall, the findings emphasize the importance of identifying for each new cultivar the most appropriate water regime in order to amplify the quality of the fruit, thus maintaining high production standards and saving water. Full article

Nitrogen (N) is an essential determinant of strawberry growth and productivity. However, plants exhibit varying preferences for sources of nitrogen, which ultimately affects its use efficiency. Thus, it is imperative to determine the preferred N source for the optimization of indoor strawberry production. This study employed the ¹⁵N-tracer technique to investigate the effects of N sources on N uptake, distribution, and use efficiency, as well as the plants’ growth, for ‘Praratchatan 80’ strawberries in a greenhouse. Five treatments were applied: T1 (5.0 mM ¹⁵NO₃⁻), T2 (2.5 mM ¹⁵NO₃⁻ + 2.5 mM NH₄⁺), T3 (5.0 mM ¹⁵NH₄⁺), T4 (2.5 mM ¹⁵NH₄⁺ + 2.5 mM NO₃⁻), and T5 (N-free, control) in a completely randomized design. Significant (p < 0.05) differences were observed in N uptake and distribution and total N concentration among the treatments. Sole NH₄⁺ promoted early N uptake and accelerated flowering, while NO₃⁻ enhanced vegetative growth and later-stage nitrogen use efficiency (NUE). The application of combined NO₃⁻ and NH₄⁺ was most efficacious, balancing the benefits of both N forms. NO₃⁻ treatment enhanced ¹⁵NUE by 46% compared to NH₄⁺, and mixed N sources demonstrated superior and consistent ¹⁵NUE over time. NH₄⁺, alone or with NO₃⁻, expedited flowering by 20 days compared to sole NO₃⁻ and N-free treatments. This study elucidates the importance of the sources of N in optimizing strawberry growth and flowering, providing a foundation for developing tailored N-management strategies. Future research should focus on refining mixed N application ratios and timings, exploring molecular mechanisms of N metabolism, and evaluating long-term impacts on strawberry production sustainability. Full article