Search Results (137)

Background: The implementation of advanced agronomical strategies, including the use of antitranspirant, in order to mitigate the negative effects of environmental stress, particularly heat stress on plants, has become a focal area of research in the Mediterranean basin. This region is characterized by hot and dry summer that affects plant physiology. Methods: The experiment was carried out in Sicily (South Italy) on 12-year-old avocado cv. Hass grafted onto Walter Hole rootstock. Two subplots each of forty homogenous trees were selected and treated (1) with calcium carbonate (DECCO Shield^®) and (2) with water (control) at the following phenological phases: 711, 712 and 715 BBCH. The climatic parameters were recorded throughout the year. Physiological measurements (leaf transpiration, net photosynthesis, stomatal conductance, leaf water potential) were measured at 105, 131 and 168 days after full bloom. Fruit growth was monitored, and physico-chemical analyses were carried out at harvest. Results: The antitranspirant increased photosynthesis and stomatal conductance and reduced leaf transpiration (−26.1%). Fruit growth rate increased during summer, although no morphological and qualitative difference was observed at harvest. PCA highlighted the positive effect of the calcium carbonate on overall plant physiology. Conclusions: Antitranspirant foliar application reduced heat stress effects by improving physiological responses of avocado trees. Full article

Utilizing edible films/coatings promises to extend the shelf life of fruits by controlling various physiological parameters (e.g., respiration and transpiration rates), maintaining firmness, and delaying fruit senescence. The influence of composite-based edible coatings made from sodium or calcium caseinate: carboxymethyl chitosan (75:25) on the postharvest quality of fresh blueberries was assessed over a 28-day storage period, on the basis of weight loss and changes in pH, firmness, color, titratable acidity, soluble solids content, mold and yeast count, and respiration rate. The pH of the blueberries increased over the period of storage, with significant differences observed between uncoated and coated (e.g., pH was 3.89, 3.17, and 3.62 at the end of the storage time for uncoated, Ca 75-1% SO, and Na 75-1% SO, respectively. Desirable lower pH values at the end of storage were obtained with the calcium caseinate formulations. Over the duration of storage, other quality parameters (e.g., firmness) were better retained in coated fruits compared to the uncoated (control) one. At the last storage day, the firmness of the uncoated sample was 0.67 N·mm⁻¹ while the sodium and calcium caseinate was 0.63 and 0.81 N.mm⁻¹, respectively. Moreover, the microbial growth was reduced in coated fruits, indicating the effectiveness of coatings in preserving fruit quality. The mold /yeast count was 1.4 and 2.3 log CFU/g for CaCa 75-1% SO and NaCa 75-1% SO compared with uncoated with 4.2 log CFU/g. Adding soybean oil to the caseinate–carboxymethyl chitosan composite edible coating has the potential to positively influence retention of various quality parameters of blueberries, thereby extending their shelf life and maintaining overall quality. Further research could explore the optimization of coating formulations and application methods to enhance their effectiveness in preserving fruit quality during storage. Full article

This study investigated the influence of cane diameter on vegetative, productive, and physiological behaviors in Actinidia chinensis, cv. Gold 3. Conducted over two years (2021–2022), the experiment compared canes with larger (HD) and smaller (LD) proximal diameters. This research focused on parameters such as shoot morphology, leaf gas exchange, fruit quality, and hydraulic resistance. The results revealed that HD canes promoted more vigorous growth, with a higher proportion of long and medium shoots, whereas LD canes resulted in shorter shoots. Additionally, the HD canes demonstrated a higher leaf area and more extensive leaf coverage, contributing to enhanced photosynthetic activity, as evidenced by enhanced gas exchange, stomatal conductance, and transpiration rates. This higher photosynthetic efficiency in HD canes resulted in more rapid fruit growth, with a larger fruit size and weight, particularly in fruits from non-terminate shoots. By contrast, fruits on LD canes exhibited slower growth, particularly in terms of fresh weight and dry matter accumulation. Despite these differences, maturation indices, including soluble solids and acidity levels, were not significantly affected by cane type. The findings suggest that selecting HD canes during winter pruning could lead to earlier harvests, with improved fruit quality and productivity, making this practice beneficial for optimizing vineyard management in Actinidia chinensis. Full article

This article addresses the impact of deficit irrigation on the agronomic and physiological performance of “Rojo Brillante” persimmon trees in a Mediterranean climate. It compares the effect of a sustained deficit irrigation (SDI; imposing water deficit uniformly throughout the entire crop cycle) strategy and two regulated deficit irrigation (RDI; enforcing a water deficit during the phenological phases that are less sensitive to water stress) strategies. Field trials were conducted from 2022 to 2024 at the Cajamar Experimental Center in Paiporta, Valencia, Spain. The trees respond to mild water stress reducing transpiration through stomatal closure. RDI resulted in modest irrigation water savings (11–16%), minimizing fruit drop, leading to an increased number of fruits per tree and a higher marketable yield, although this came at the cost of a reduced unit fruit weight. SDI achieved a 30% reduction in irrigation water usage without impacting on the marketable yield, but it also caused a decrease in unit fruit weight. RDI increased water productivity (yield obtained per amount of water applied) primarily through higher yields, while SDI improved productivity mainly by lowering the amount of irrigation water applied. Both irrigation strategies are recommended for cultivating “Rojo Brillante” persimmons. RDI is especially advisable in years with lower fruit loads as more intensive thinning may be necessary in years with higher fruit loads. Conversely, SDI is recommended in situations where water availability is limited. Full article

Calcium (Ca²⁺) is a macronutrient essential for the growth, development, yield, and quality of vegetables and fruits. It performs structural, enzymatic, and signaling functions in plants. This review examines Ca²⁺ translocation from soil to the fruit via the plant xylem network, emphasizing the importance of Ca²⁺ compartmentalization within fruit cell organelles in the development of calcium deficiency disorders such as blossom-end rot (BER). The underlying causes of BER and potential control measures are also discussed. Soil-available Ca²⁺, transported by water flow, enters the root apoplast through membrane channels and moves toward the xylem via apoplastic or symplastic routes. The transpiration force and the growth of organs determine the movement of Ca²⁺-containing xylem sap to aerial plant parts, including fruits. At the fruit level, the final step of Ca²⁺ regulation is intracellular partitioning among organelles and cellular compartments. This distribution ultimately determines the fruit’s susceptibility to Ca²⁺-deficiency disorders such as BER. Excessive sequestration of Ca²⁺ into organelles such as vacuoles may deplete cytosolic and apoplastic Ca²⁺ pools, compromising membrane integrity and leading to BER, even when overall Ca²⁺ levels are adequate at the blossom end. Effective BER management requires cultural and physiological practices that promote Ca²⁺ uptake, translocation to the fruit, and appropriate intracellular distribution. Additionally, the use of BER-resistant and Ca²⁺-efficient cultivars can help mitigate this disorder. Therefore, a comprehensive understanding of Ca²⁺ dynamics in plants is critical for managing BER, minimizing production loss and environmental impacts, and maximizing overall crop productivity. Full article

Large-fruited cranberry (Vaccinium macrocarpon Aiton) is a species known for its highly valued fruit and is typically propagated vegetatively through the rooting of stem cuttings. Studies on the rooting of stem cuttings of large-fruited cranberry have shown that the morphological traits of the root system are a key indicator of the effectiveness of this process. To support rooting, gel coatings based on polysaccharides and containing auxins, especially the indole-3-butyric acid (IBA) W4 variant, were developed and applied. These significantly influenced root length (increase of 44.6% compared to control W0), surface area (increase of 32.4% compared to W0), volume (increase of 26.7% compared to W0), and average thickness, which translated into better nutrient uptake and a higher degree of plant nourishment. The W4 coating, combining mineral components, polysaccharides, and IBA, reduced transpiration and maintained moisture, promoting effective rooting. The associated metabolic changes were confirmed by analyses of oxidative stress markers and chlorophyll fluorescence. The study demonstrated that enhanced root system development was closely linked with the increased accumulation of macro- and micronutrients in the aerial parts of the plants, directly contributing to improved growth and potential yield. These findings highlight that effective rooting—achieved through the targeted metabolic stabilisation of the rooting environment—is essential for the successful vegetative propagation of large-fruited cranberry. Full article

The potato (Solanum tuberosum L.) is highly dependent on water availability, with physiological sensitivity varying throughout its phenological cycle. In the context of increasing water scarcity and greater climate variability, identifying critical periods where water stress negatively impacts productivity and tuber quality is essential. This study evaluated the physiological response of potatoes under different deficit irrigation strategies in field conditions, and aimed to determine the irrigation reduction thresholds that optimize water use efficiency without significantly compromising yield. Five irrigation regimes were applied: well-watered (T1; irrigation was applied when the volumetric soil moisture content was close to 35% of total water available), 130% of T1 (T2, 30% more than T1), 75% of T1 (T3), 50% of T1 (T4), and 30% of T1 (T5). Key physiological parameters were monitored, including gas exchange (net photosynthesis, stomatal conductance, and transpiration), chlorophyll fluorescence (Fv’/Fm’, ΦPSII, electron transport rate), and photosynthetic pigment content, at three critical phenological phases: tuberization, flowering, and fruit set. The results indicate that water stress during tuberization and flowering significantly reduced photosynthetic efficiency, with decreases in stomatal conductance (gs), effective quantum efficiency of PSII (ΦPSII), and electron transport rate (ETR). In contrast, moderate irrigation reduction (75%) lowered the seasonal application of water by ~25% (≈80 mm ha⁻¹) while maintaining commercial yield and tuber quality comparable to the fully irrigated control. Intrinsic water use efficiency increased by 18 ± 4% under this regime. These findings highlight the importance of irrigation management based on crop phenology, prioritizing water supply during the stages of higher physiological sensitivity and allowing irrigation reductions in less critical phases. In a scenario of increasing water limitations, this strategy enhances water use efficiency while ensuring the production of tubers with optimal commercial quality, promoting more sustainable agricultural management practices. Full article

The packaging of perishable products, such as fruits, contributes to their preservation during storage and safe transportation. The use of suitable packaging materials contributes to forming a desirable atmosphere inside the package so that the level of respiration, transpiration, and ethylene emission can be kept low. However, it would be useful for consumers to know relevant information on the deterioration rate of different types of fruit (tree fruits, berries, stone fruits, and aggregate accessory fruits). The technology of intelligent and active packaging systems (smart packaging) enables the provision of information related to the deterioration rate of fruits to consumers and, in parallel, extends the shelf life of fruits and other plant-based foods, maintaining a high quality. Intelligent packaging systems include biosensors and gas sensors, along with microbial, freshness, and time–temperature indicators. On the other hand, the active packaging system includes the use of moisture, odor, and gas absorbers, along with antioxidant and antimicrobial agents to maintain the quality of plant-based foods and extend their shelf life. This review article aims to make an in-depth evaluation of the most relevant literature on this topic by highlighting the challenges, trends, and future directions related to different types of fruits. Full article

The online dynamic collection of irrigation and plant physiological information is crucial for the precise irrigation management of nutrient solutions and efficient crop cultivation in vegetable soilless substrate cultivation facilities. In this study, an intelligent weighing system was installed in a tomato substrate cultivation greenhouse. The monitored values from the intelligent weighing system’s pressure-type module were used to calculate irrigation start–stop times, frequency, volume, drainage volume, drainage rate, evapotranspiration, evapotranspiration rate, and stomatal conductance. In contrast, the monitored values of the suspension-type weighing module were used to calculate the amount of weight change in the plants, which supported the dynamic and quantitative characterization of substrate cultivation irrigation and crop growth based on an intelligent weighing system. The results showed that the monitoring curves of pressure and flow sensors based on the pressure-type module could accurately identify the irrigation start time and number of irrigations and calculate the irrigation volume, drainage volume, and drainage rate. The calculated irrigation amount was closely aligned with that determined by an integrated-water–fertilizer automatic control system (R² = 0.923; mean absolute error (MAE) = 0.105 mL; root-mean-square error (RMSE) = 0.132 mL). Furthermore, transpiration rate and leaf stomatal conductance were obtained through inversion, and the R², MAE, and RMSE of the extinction coefficient correction model were 0.820, 0.014 mol·m⁻²·s⁻¹, and 0.017 mol·m⁻²·s⁻¹, respectively. Compared to traditional estimation methods, the MAE and RMSE decreased by 12.5% and 15.0%, respectively. The measured values of fruit picking and leaf stripping linearly fitted with the calculated values of the suspended weighing module, and R², MAE, and RMSE were 0.958, 0.145 g, and 0.143 g, respectively. This indicated that data collection based on the suspension-type weighing module could allow for a dynamic analysis of plant weight changes and fruit yield. In summary, the intelligent weighing system could accurately analyze irrigation information and crop growth physiological indicators under the practical application conditions of facility vegetable substrate cultivation, providing technical support for the precise management of nutrient solutions. Full article

The fruit ripening season for the rabbiteye blueberry often coincides with periods of heavy rainfall in central–eastern China. The use of rain shelters to protect fruit from rainfall damage has increased worldwide due to global climate anomalies. However, the effects of rain-shelter cultivation on the photosynthesis and fruit characteristics of the rabbiteye blueberry have not yet been fully explored. In the present study, 4-year-old container-grown rabbiteye blueberry plants were covered with polyethylene (PE) film from the berry coloration stage until fruit were harvested for three consecutive years in Nanjing, China. The results showed that rain-shelter cultivation did not affect the air temperature and relative humidity, but significantly reduced the photosynthetically active radiation and UV radiation reaching the canopy zone. However, the rain shelter conditions did not significantly decrease the net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (E) of the rabbiteye blueberry leaves. Additionally, the fruit yield and berry weight of blueberries cultivated under the rain shelter were not significantly affected. Furthermore, no significant differences were observed in total soluble solids, acidity, and total flavonoids content between fruits grown under the rain shelter and in the open field in all experimental years, but a significant decrease in total polyphenols and anthocyanins content was observed in fruits grown under the rain shelter in years with less rainfall. Our results suggest that simple rain shelter cultivation did not noticeably affect the photosynthesis and fruit yield of container-grown rabbiteye blueberry in rainy areas of central–eastern China, but its effects on the fruit quality vary depending on rainfall during the fruit ripening period. Full article

Lonicera caerulea is a species known for its fruit with a rich health-promoting composition and the high frost resistance of its bushes. The increase in the popularity of this species and the number and area of plantations increases the risk of diseases and pests. However, the use of ozone gas may involve the risk of physiological damage to the plant. In this experiment, in 2022–2023, the physiological response of six varieties of Lonicera caerulea L. to gaseous ozone at a concentration of 5 ppm·1 min, 5 ppm·3 min and 5 ppm·5 min was determined. The flavonoid–nitrogen index (NFI) remained unchanged at 0.33 in both non-ozonated leaves and those exposed to a 5 ppm·3 min dose of ozone. In general, ozonation did not lead to significant changes in the physiological parameters observed for most of the varieties studied. The mean performance index (P_itotal) value of the ozonated leaves decreased by 23.1% for LE ‘Lori’ and 23.8% for ‘139-24’, after applying an ozone dose of 5 ppm·5 min in 2022. A significant decrease of 34.3% in the average transpiration rate (E) was observed after the use of 5 ppm·5 min ozone in plants of the variety ‘21-17’ across both years of cultivation. The different effects of the ozone doses used may indicate different reactions depending on the variety used and the year of cultivation. Overall, the study found that ozone does not have a phytotoxic effect on most varieties, which may indicate different reactions and differences between varieties. The use of an appropriate dose of ozone did not cause any disruption in the selected physiological parameters of Lonicera caerulea L. plants. The absence of phytotoxicity in some varieties may allow the use of ozonation treatments in agriculture; however, further research on the long-term effects on plants is required. Full article

Organic agriculture has few tools against pests and diseases and is constantly looking for effective and sustainable products such as geomaterials, i.e., zeolite. This study evaluates the physiological and morphological responses of olive plants (Olea europaea) to foliar applications of different geo-materials, specifically kaolin, natural zeolite, and ammonium-enriched zeolite. The research examines leaf anatomical modifications, including internal tissue structures, trichome and stomatal density, chlorophyll content, and gas exchange parameters, alongside the impact on fruit development and extra virgin olive oil (EVOO) quality. Results indicate that kaolin application negatively influenced transpiration and stomatal conductance, an effect corroborated by increased xylem vessel wall thickness. However, the reduction in stomatal conductance was attributed to a functional rather than morphological adaptation, as no significant changes in stomatal density or size were observed. Both geo-material treatments altered leaf surface properties, particularly peltate trichome characteristics. Notably, ammonium-enriched zeolite application enhanced photosynthetic rate during early olive development, likely due to its nutritional role, and contributed to increased fruit size and oil yield. These findings highlight the potential of geo-material-based foliar treatments as an effective strategy to optimize plant physiological performance and improve olive oil production in sustainable agricultural systems. Full article

Calcium (Ca²⁺) plays a fundamental role in metabolic processes, and it is involved in several structural functions at the cell level, such as vacuole osmotic regulation, cell wall strengthening, and plasma membrane stability, as well as acting as a secondary messenger for several different signals. The role of Ca²⁺ in signal transduction and cell wall organization is crucial for stress responses, cell activity, and plant tissue development. In addition, Ca²⁺ is essential in modulating enzymatic activities, hormonal control, water, and ion transport across the plasma membrane. Although calcium’s role in fruit trees is well studied, many of its specific functions in kiwifruit remain unclear, including the optimal amount of Ca²⁺ in fruit and its distribution in fruit cells for the best pre- and post-harvest fruit quality. Calcium transport to the fruit is mainly regulated by the xylem sap flow; however, the contribution of fruit transpiration and the requirements of fruit cells are not clear. Understanding the kinetics of Ca²⁺ accumulation in fruit under different environmental conditions can help establish correct nutrient management. This review addresses the current knowledge on Ca²⁺ involvement in plant physiology, metabolic processes, structural functions, and fruit growth, quality, and storage, with particular emphasis on Actinidia chinensis. In addition, the different analytical techniques used for the quantification and definition of Ca²⁺ in different plant organs, including stain technology, X-rays, and advanced imaging methods, are here explored. Full article

Calcium (Ca) and Boron (B) are structural components of the cell wall with limited phloem mobility. The absorption, movement, and distribution of these two nutrients have a greater effect on leaves than on fruits since their transport is dependent on transpiration flow. This research aimed to study the absorption and movement of ⁴⁵Ca applied to the soil and the fruit of sweet cherry trees under B-deficient and B-adequate soil conditions. In the first experiment, ⁴⁵Ca was applied to the soil surface before the occurrence of leaf senescence. Soil and tree components were sampled and analyzed 6 months after ⁴⁵Ca application. The second experiment involved a ⁴⁵Ca application to the surface of small fruits with 5 mm diameters, which were analyzed after 45 days. The tree Ca allocation in the B-deficient soil condition was significantly fewer in shoots and higher in roots, contrary to the B-adequate soil. On the other hand, the fruit evidenced significant differences in Ca levels in the edible portion of the fruit (i.e., the flesh and peel), which was higher in the B-adequate soil condition. Therefore, under B-deficient soil, Ca was ‘retained’ in the root system and in the fruit pit, suggesting a synergistic mechanism between Ca and B. This mechanism might indicate a survival ecological function where B triggers biological signals to restore Ca homeostasis. Full article

Rapid urbanization and increasing land scarcity have made urban agriculture and efficient space utilization critical directions in modern agriculture. Ougan, a fruit tree valued for both its economic and ecological benefits, holds significant promise for dwarfing cultivation techniques. In this study, a root-irrigation method was used to apply paclobutrazol at various concentrations (200, 500, 1000, 1500, and 2000 mg/L) to Ougan seedlings, with a control group for comparison. Growth parameters include an average daily increase of plant height, stem girth, new branches, and new branch girth, as well as physiological indices such as leaf SPAD values, leaf nitrogen content, net photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, and transpiration rate, were measured during both spring and summer growth periods. The results demonstrate that PBZ exerts a distinct concentration-dependent regulatory effect on Ougan growth: higher concentrations significantly inhibited plant height while promoting increases in stem diameter, with several parameters exhibiting a unimodal response. Short-term (spring) PBZ application enhanced certain photosynthetic parameters, such as net photosynthetic rate and stomatal conductance; however, prolonged exposure (summer) resulted in a decline in photosynthetic efficiency and overall leaf physiological status. Through comprehensive evaluation using principal component analysis and PLS-SEM, the 500 mg/L PBZ treatment was identified as achieving the optimal balance between growth inhibition and the maintenance of photosynthetic and nutritional status, closely approximating the ideal dwarfing effect. This study elucidates the complex regulatory effects of PBZ on the growth, photosynthesis, and carbon assimilation of Ougan through natural climate, providing robust technical parameters and theoretical support for future dwarf cultivation practices. These findings facilitate the development of dwarf fruit trees into bonsai vegetation, demonstrating significant horticultural application potential. Full article