Pomegranate Fruit Quality Research Articles

Differential effects of environmental conditions on the commercially important attributes and postharvest quality of pomegranate fruit

Differential effects of environmental conditions on the commercially important attributes and postharvest quality of pomegranate fruit

Impact of some fixed and essential oils application on fruit quality of pomegranate during cold storage.

Impact of some fixed and essential oils application on fruit quality of pomegranate during cold storage.

Potential of sustained deficit irrigation to enhance biological and nutritional quality of pomegranate fruit during storage

BackgroundWhile water availability is important for quality at harvest, it also continues to influence the quality of pomegranates during storage. Reducing the amount of irrigation, in addition to water saving has different effects on bioactive compounds of pomegranate during storage time. This study was conducted to determine the influence of irrigation level on fruit quality changes during storage period of two commercial Iranian pomegranate cultivars (‘Shishecap’ and ‘Malas-Yazdi’). Sustained deficit irrigation (SDI) was applied to plants that received 75% (moderate stress) or 50% (severe stress) of their normal water requirement. A control group received 100% of their water requirement.ResultsAt harvest time and during storage period, fruit weight loss and some biochemical traits such as fruit total soluble solids (TSS), titratable acidity (TA), pH, total phenolic compounds (TPC), total anthocyanins content (TAC), antioxidant activity and vitamin C were measured in pomegranate fruits. Also, the quantity of the produced product was also measured at the time of harvesting. Results indicated that control fruits exhibited more weight loss than those produced under water deficit during the storage period in both years. According to results, fruit TSS, TAC, and antioxidant activity significantly increased during storage period but fruit TA and vitamin C significantly decreased throughout storage period. Also, reduction in irrigation level resulted in a decline in the yield.ConclusionsThis study revealed a crucial link between irrigation level and the quality of pomegranate fruits, despite a reduction in the yield. This included affecting weight loss and the content of bioactive compounds, both at harvest and during storage.

Enhancing the fruit yield and quality of pomegranate in a new niche area: Insights into site specific agronomic practices

The sustained higher profitability of a pomegranate orchard relies heavily on the production of a greater proportion of high-quality fruits, a goal achievable through the implementation of effective management practices. The objective of this study is to provide site-specific supplementary knowledge regarding the response of pomegranate plants to various management practices under arid conditions. With the aim of enhancing both marketable fruit yield and quality of pomegranate in arid regions, four separate and simultaneous experiments were conducted in the same orchard to evaluate (i) the response of planting materials derived from tissue culture, air layering, and cutting; (ii) the impact of crop (fruit) load; (iii) the response of crop regulation; and (iv) the application response of organo-mineral fertilizers containing potassium (OMF-K) and phosphorus (OMF-P). The results obtained for plant growth, fruit yield, and fruit quality did not exhibit significant differences among pomegranate plants raised through the three different methods of vegetative propagation. Striking results in terms of producing superior-grade fruits, higher marketable yield, and overall fruit quality were achieved with crop loads of 80 fruits per plant. Staggering the crop regulation from June to September effectively extended the harvesting season to four months, from the last week of November to March, with eventual benefit of reduced fruit cracking compared to the standard two-month harvesting period obtained from normal regulation. Soil application of the indigenously developed OMF-K in two equal splits, along with the recommended N and P through inorganic sources, significantly reduced fruit cracking (only 6.23%) compared to the recommended NPK through inorganic sources (26.9%), while maintaining similar physicochemical quality attributes.

Effect of Pit and Soil Types on Growth and Development, Nutrient Content and Fruit Quality of Pomegranate in the Central Deccan Plateau Region, India

To enhance pomegranate production on marginal gravelly lands, standardized planting techniques were evaluated in an 8-year-old orchard. Trenching, wider pit excavation, pit digging, and auger digs with dimensions of 1 and 2 m were employed. Utilizing native soil from barren land, with or without spent wash, and mixing it with black soil up to 1 m deep, growth parameters, leaf nutrients, fruit production, and fruit quality were assessed. The trench and wider pit methods outperformed others, yielding greater above-ground biomass (>70.3 kg tree−1), root biomass (>24.5 kg, tree−1), and cross-sectional area (>3.30 m2 tree−1). These methods also produced longer roots (>4.0 m tree−1) and higher leaf phosphorus (>0.28%) and potassium (>1.81%) levels, fruit juice content (>48.50%), and total soluble solids (>16.05°) compared to other planting methods. This resulted in higher and more sustainable fruit yield production under the trench and wider pit planting methods (>7.21 t ha−1). Similarly, the native and black soil mixture produced healthy fruit trees, improved fruit quality, and sustainably higher fruit yield over the native soil alone. In summary, the trench and wider pit methods (2–3 m3), combined with a soil mixture, are recommended for sustainable, high-quality fruit production in shallow gravelly terrains, thereby improving food security and the livelihoods of farmers in arid regions.

Impact of PGRs, polyamines and potassium to improve pomegranate flowering behaviour, fruit set and fruit quality

Ever changing climate is affecting the flowering pattern in pomegranate worldwide. It is the need of the hour to find out some chemicals that can not only enhance hermaphrodite flowers and fruit set but also enhance fruit quality. The present investigation aimed to evaluate the effect of plant growth regulators (three), polyamines (two) and other chemicals (five) on photosynthesis, flowering ratio, fruit set and quality of pomegranate fruits. Pomegranate trees were treated at full leaf expansion stage. Potassium dihydrogen phosphate (5000 ppm), spermidine (1.5 ppm) and naphthalene acetic acid (NAA) (20 ppm) were the best treatments to significantly enhance hermaphrodite flowers, as the hermaphrodite to male flower ratio was 0.39, 0.37, and 0.35, respectively, compared to 0.22 in the control treatment. Except spermidine, NAA and paclobutrazol, all treatments increased the fruit setting significantly, with potassium dihydrogen phosphate (5000 ppm) being the most effective treatment with 66% fruit set compared to 43% in control trees. In mature fruits, compared to control, NAA enhanced total phenols, ascorbic acid and total antioxidants (3%, 15%, 7%, respectively) followed by ascorbic acid treatment (250 ppm); potassium dihydrogen phosphate (5000 ppm) and putrescine (44 ppm) enhanced the anthocyanin content and hence aril color significantly (11% and 10% respectively). Though the use of NAA in pomegranate production is commercial practice, two sprays of ascorbic acid can also be included to enhance the nutritional quality of fruits. Foliar application of potassium dihydrogen phosphate twice at flowering stage could be highly useful for quality pomegranate production due to the enhanced number of hermaphrodite flowers, fruit setting and fruit color. Overall, use of these chemicals can be beneficial to pomegranate farmers to get more remuneration from harvest.

Improving quality of seedless Rawa pomegranate fruits by using bagging and spraying with calcium

Improving quality of seedless Rawa pomegranate fruits by using bagging and spraying with calcium

Fruit quality, antioxidant, and mineral attributes of pomegranate cv. Ghojagh, influenced by shading and spray applications of potassium sulfate and sodium silicate

Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and ⁰hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality.

Physicochemical characteristics of pomegranate fruits as affected by foliar application of potassium and zinc

Foliar application of mineral nutrients can considerably improve fruit yield and quality. In this study, the effects of K and Zn application by spraying on leaf mineral contents, and some physical and biochemical characteristics of pomegranate fruits cv. ‘Malas Saveh’ were investigated. The mineral treatments were three concentrations of K2SO4 (0, 1, and 2%) and three concentrations of ZnSO4 (0, 0.5, and 1%). The solutions were applied in 2020–2021 and in four times: the first application was during the time of flowering and rest three applications were applied at two-week intervals. The results showed that leaves of trees fed with different concentrations of K2SO4 and ZnSO4 accumulated higher concentrations of N, P K, Zn, Fe, and Mn than those untreated. Pomegranate trees treated with the mineral treatments had higher chlorophyll a and total chlorophyll. Applying most mineral treatments, especially 2% K2SO4+0.5% ZnSO4, significantly increased the fruit yield, fruit diameter, fruit length, aril percentage, aril/skin, the weight of 100 arils, and juice content of 100 g arils, but reduced the cracking percentage, skin thickness, skin percentage and firmness of fruits. Moreover, fruits of pomegranate trees treated with the most mineral treatments and especially 2% K2SO4+0.5% ZnSO4, showed a greater level of TSS (total soluble solids), TSS/TA (total soluble solids/titratable acidity), anthocyanin, total phenol, flavonoid, antioxidant activity, and vitamin C, and a lower level of TA. The study results evidenced that K and Zn application by spraying has a high potential for improving fruit yield and quality of pomegranate.

Impact of Pollination on Pomegranate

Pollination mode affects crop quality and quantity in several economically significant crops. This study examined the effects of open pollination, Apis cerana pollination, hand, hand+ self-pollination, and self-pollination on pomegranate fruits. Open-pollinated plants had higher fruit length, weight, rind thickness, total soluble sugars, reducing sugar content, non-reducing sugar content, and total soluble solids, followed by A. cerana pollinated plants. A. cerana pollination increased pomegranate output and quality, including fruit shape, aril weight, TSS, and sugar content. The study found that open pollination and A. cerana integration increase pomegranate fruit yield and quality. A. cerana integration boosts farmers' income and conserves biodiversity.

The Simultaneous Use of 1-Methylcyclopropene and Methyl Jasmonate Vapor as an Innovative Strategy for Reducing Chilling Injury and Maintaining Pomegranate Fruit Quality at Suboptimal Temperatures.

Spain is one of the main contributors to global pomegranate production. Pomegranate presents a challenge for preservation at suboptimal temperatures. Preserving this fruit for an extended period is challenging due to its susceptibility to chilling injury (CI). For this reason, we have examined different postharvest treatments to extend the pomegranate shelf life and their potential impact on reducing CI. For this reason, two postharvest treatments have been applied: 1-Methylcyclopropene (1000 nL L-1 1-MCP) and methyl jasmonate vapors (0.01 mM MeJA), a natural elicitor found in many plant organs that induces a wide range of physiological processes, including the activation of defense mechanisms against stress. Following the application of these treatments and subsequent fruit storage at 2 °C for 90 days, maintenance of firmness and membrane integrity was observed. Additionally, a positive synergic effect was observed in these quality traits when combining both substances (1-MCP + MeJA), especially with regard to delaying weight loss, the external color evolution, and total polyphenol accumulation. On the other hand, MeJA treatment alone or in combination with 1-MCP also increased the anthocyanin content in arils, thereby enhancing the fruit quality. In general, the best results were observed when these two different technologies were applied as a combined treatment, especially in terms of maintaining quality traits such as fruit firmness and total acidity and reducing weight loss and CI. This is the first time that these two substances have been tested together in any fruit species, and their simultaneous application in the same container represents an innovative approach that could be an interesting tool for commercial purposes.

Fruit thinning improves pomegranate fruit quality by activating physical, physiological, biochemical and bioactive attributes

Fruit thinning improves pomegranate fruit quality by activating physical, physiological, biochemical and bioactive attributes

Role of Plant Growth Regulators and Eco-Friendly Postharvest Treatments on Alleviating Chilling Injury and Preserving Quality of Pomegranate Fruit and Arils: A Review

Role of Plant Growth Regulators and Eco-Friendly Postharvest Treatments on Alleviating Chilling Injury and Preserving Quality of Pomegranate Fruit and Arils: A Review

Unraveling the mechanisms behind salt stress alleviation and enhanced fruit storability in pomegranate through triacontanol treatment

Salt stress is a significant factor that leads to various detrimental effects on pomegranate trees. This study was undertaken with the primary objective of developing a treatment strategy aimed at mitigating the adverse impacts of salinity in fields, and its negative reflections on the post-harvest quality of pomegranate fruit. At the commencement of the study, we utilized response surface methodology (RSM) to assess a range of triacontanol (TRA) concentrations along with different spray frequencies. Our investigation revealed that applying 10 and 20 µM TRA three times proved to be the most effective treatments. Accordingly, the effect of these concentrations was studied in depth. The treatment with TRA at concentrations of 10 and 20 µM demonstrated significant positive effects. TRA effectively mitigated the harmful impacts of salinity, preserved the plant's nutrient and antioxidant content, and led to an increase in productivity. Moreover, TRA treatments had a notable effect on enhancing post-harvest storability of fruits during storage at 5 ̊C and 90 % RH for 12 weeks. TRA treatments resulted in higher concentrations of mineral nutrients (N, P, K, and Ca), porphyrin concentration, relative water contents, activities of CAT, POD, and SOD, glycine betaine, proline, amino acids, total phenolics, and total carbohydrates, additionally, TRA treatments led to increased fruit weight and fruit yield compared to the control group. Moreover, TRA treatments attained lower hydrogen peroxide, membrane permeability, malondialdehyde, Na, and Cl compared with control. Indeed, the positive effects of TRA treatments extended to fruit storability. TRA treatments resulted in a notable decrease in the percentage of decay, weight loss, and softness. Furthermore, TRA treatments demonstrated efficacy in preserving TSS, husk color, ascorbic acid, and anthocyanin content in the arils. These combined benefits highlight the potential of using TRA as a practical and effective method to alleviate salt stress and enhance pomegranate fruit storability.

Conventional vs. nano-micronutrients as foliar fertilization for enhancing the quality and nutritional status of pomegranate fruits

Currently, nanotechnology is widely used in agriculture and horticulture. Nanofertilizers are essential for encouraging vegetative growth and flowering, as well as enhancing productivity and fruit quality. These nanoparticles are viewed as growth promoters as well. The current study was therefore carried out during the two successive seasons of 2021 and 2022 on 14-year-old trees grown in clay soil in a field experiment at the Pomology Department Research orchard, Faculty of Agriculture, Assiut University, Egypt. The effects of conventional vs. nano-micronutrients as foliar fertilizers on the fruit yield, quality, and mineral nutrition status of pomegranate trees were studied. The foliar application of all treatments on pomegranate trees remarkably increased yield and physical properties of fruits as well as improved the levels of total soluble solids percentage, anthocyanin pigment, flavonol, total phenols, antioxidant activity and nutrients status compared with the controls during the 2021 and 2022 seasons. The lowest fruit cracking percentages were obtained by the spraying of nano-micronutrients (4.33–5.70 %) compared with the other treatments and the control, which gave the highest percentages (10.45–11.43 %). The highest increments in yield, physical properties of fruits and levels of total soluble solids percentage, anthocyanin pigment, flavonol, total phenols, and antioxidant activity were noticed by the spraying of nano-micronutrients especially at 1000 and/or 1500 µg mL−1. It could be concluded that the use of nanofoliar fertilization in pomegranate cultivation may improve the yield, quality, and nutritional status of pomegranate fruits.

Grading of Pomegranate Fruit using CNN

Farmers require an automated system to grade Pomegranate fruits rather than a manual system to increase productivity and quality of Pomegranate fruits. Manual grading of fruits does not produce adequate results and requires additional time for disease identification and gradation, as well as the expertise of an expert, making it ineffective. The suggested system is an efficient module that identifies various pomegranate fruit disorders and determines the stage of sickness. Effective growth stage monitoring and disease detection are critical for maximising pomegranate fruit yield and quality. This paper describes a method for monitoring the growth stages of pomegranate fruit utilising image processing techniques and disease detection approaches based on machine learning algorithms. The suggested method analyses colour, shape, and texture information taken from photos captured at various phases of development to track the growth stages of pomegranate fruit. The obtained data is then utilised to train machine learning models that appropriately distinguish the growth stages. The models are trained on a dataset of annotated photos containing numerous pomegranate fruit illnesses. Farmers and agricultural specialists can use the developed technology to correctly monitor the growing phases of pomegranate fruit and detect problems. The camera in this project catches various pomegranate fruit stages and classifies pomegranate fruits into two classes: infected and non-infected, using a machine learning algorithm and Python tools. This study employs a CNN, K-mean method, and image processing technique to detect illnesses at various phases of fruit development.

Optimizing nitrogen, phosphorus and potassium fertilization for pomegranate fruit and juice quality

Optimizing nitrogen, phosphorus and potassium fertilization for pomegranate fruit and juice quality

Ultrasound treatment alleviates external pericarp browning and improves fruit quality of pomegranate during storage.

Ultrasound treatment has a beneficial role in horticultural production from harvest to consumption. The quality traits and microbiological load in pomegranate fruit were explored during 30 days' storage at 20 °C after 10 min and 30 min ultrasound treatments. Ultrasound treatment significantly reduced the microbiological load during storage, providing a relatively clean and suitable storage environment. This was especially true for the 30 min treatment, which also maintained relatively lower weight loss and kept the browning rate below 5% during storage. Meanwhile, the fruit treated with ultrasound had higher ascorbic acid and anthocyanin content, which provided better antibacterial properties and higher nutraceutical properties until the end of storage. The 30 min ultrasound treatment significantly delayed the decrease in catalase (CAT) enzyme activity and the increase in peroxidase (POD) enzyme activity. Combined with weighted gene co-expression network analysis (WGCNA), and correlation analysis, color indicators and antioxidant activity induced by ultrasound treatment were responsible for the relatively higher fruit quality of pomegranate. Ultrasound treatment can improve the sensory quality and nutritional characteristics of pomegranate fruits during storage, and reduce the microbiological load. Ultrasound for 30 min was better than 10 min for prolonging the storage life of pomegranate. Our results will provide valuable information for ultrasound application in other horticultural products. © 2023 Society of Chemical Industry.

Improvement of Fruit Quality and Phytochemical Components of Pomegranate by Spraying with B2O3 and ZnO Nanoparticles

Pomegranate is one of the most important and widely distributed trees. Boron and zinc are important nutrients for plant growth and fruit quality. Nanotechnology has emerged as one of the most innovative scientific fields in agriculture. This study was conducted to describe the changes in the physiochemical characteristics (weight, diameter, length, firmness and color), as well as the phytochemicals attributes (total phenolics, total flavonoids, ascorbic acid, anthocyanin and antioxidant %) and minerals contents, of pomegranates fruits of the ‘Wonderful’ cultivar as a result of spraying pomegranate trees using nanomaterials (zinc oxide (ZnONPs) and boron oxide (B2O3NPs)). In three successive developmental stages (full bloom, 6 weeks after full bloom and one month before harvest time), the trees were sprayed with 0.25, 0.5 and 1 g/L ZnONPs, as well as 0.25, 0.5 and 1 g/L B2O3NPs during the 2021 and 2022 seasons. The application of ZnONPs and B2O3NPs influenced the qualitative characteristics of the fruits in the studied seasons. The highest marketable % was observed for the 0.50 and 1 g/L ZnONPs and 1 g/L B2O3NPs compared to the other treatments. Also, a positive effect was recorded for the ZnONPs and B2O3NPs on the fruits’ physical properties. All of the ZnONP and B2O3NP treatments resulted in increasing the total phenolic, flavonoid, anthocyanin and ascorbic acid contents and the antioxidant activity in the pomegranate juices. In conclusion, our results suggest that spraying pomegranate trees with ZnONPs and B2O3NPs improves the marketable fruit, enhances the fruit quality and increases the bioactive components and antioxidant activity.

Improving the storage quality of pomegranate fruit by combining modified atmosphere packaging and Origanum syriacum volatile essential oil

Improving the storage quality of pomegranate fruit by combining modified atmosphere packaging and Origanum syriacum volatile essential oil