Fruit Quality Research Articles

Combining Ability and Hybrid Breeding in Tunisian Melon (Cucumis melo L.) for Fruit Traits

A half-diallel cross study of seven melon inbred lines was carried out. The seven parents and their 21 F1 hybrids were evaluated for precocity of maturity, average weight per fruit, and fruit quality (fruit size, rind thickness, and soluble solids). The Diallel analysis was investigated for breeding values of these melon genotypes via general and specific combining ability, relationships between general and specific combining ability, and heterosis for the evaluated traits. The analysis of variance of the traits evaluated indicated highly significant differences among genotypes, suggesting the presence of adequate genetic variation for breeding. Additive genetic effects were most important with respect to fruit weight, while genetic dominance and epistasis effects mainly controlled fruit quality traits (fruit size, rind thickness, and TSS). Parent 1 (P1) and parent 3 (P3) had significant positive general combining ability effects for fruit weight. Also, P3 had positive general combining ability effects for fruit length and diameter, and cavity diameter. P3 was found to show maximum significant GCA in the desirable direction for all the traits except for TSS. Evaluation of heterosis (%) revealed that hybrid P1 × P3 can be considered as the best-performing hybrid for average fruit weight, TSS, and precocity, which also exhibited the highest positive and significant SCA effect for these traits. These results suggested that, among the melon genotypes studied, there is the potential to generate superior new varieties in hybrid production.

Implementing Internet of Things for Real-Time Monitoring and Regulation of Off-Season Grafting and Post-Harvest Storage in Citrus Cultivation: A Case Study from the Hilly Regions of Nepal

Citrus fruit cultivation, especially mandarin oranges, is crucial to the economy of Nepal’s hilly regions due to their ideal geoclimatic conditions. Despite its economic importance, the sector faces several challenges, such as inadequate grafting techniques, low-quality saplings, and ineffective post-harvest storage. This paper explores these issues and proposes innovative solutions through the use of Internet of Things (IoT) technology. To address these challenges, we identified key areas for improvement. First, we focused on extending grafting practices during the off-season to ensure a higher success rate and better-quality saplings. Second, we examined different post-harvest storage methods to determine their effectiveness in terms of shelf life, decay loss, and quality of fruit. In addition to exploring post-harvest strategies, this paper provides preharvest recommendations for farmers, emphasizing methods to enhance fruit quality and longevity through effective pre-storage practices. Our IoT-based approach introduces off-season grafting in polyhouses and advanced monitoring for post-harvest storage. The results are promising: We achieved grafting success rates of 91% for acid lime and 92% for local mandarin orange varieties. Additionally, our research compared different post-harvest storage methods for mandarin oranges, including room, cellar, and cold chamber. We assessed these methods based on shelf life, physiological weight loss, and the total soluble solids (TSS) to titratable acidity (TA) ratio. The cold chamber proved to be the most effective method, offering superior conditions for storing mandarin oranges. The IoT-based monitoring system played a crucial role in maintaining optimal temperature, humidity, and gas content within the cold chamber, resulting in reduced post-harvest losses and extended shelf life. These findings highlight the transformative potential of IoT technology in mandarin orange cultivation and post-harvest storage.

Implementing Internet of Things for Real-Time Monitoring and Regulation of Off-Season Grafting and Post-Harvest Storage in Citrus Cultivation: A Case Study from the Hilly Regions of Nepal

Citrus fruit cultivation, especially mandarin oranges, is crucial to the economy of Nepal’s hilly regions due to their ideal geoclimatic conditions. Despite its economic importance, the sector faces several challenges, such as inadequate grafting techniques, low-quality saplings, and ineffective post-harvest storage. This paper explores these issues and proposes innovative solutions through the use of Internet of Things (IoT) technology. To address these challenges, we identified key areas for improvement. First, we focused on extending grafting practices during the off-season to ensure a higher success rate and better-quality saplings. Second, we examined different post-harvest storage methods to determine their effectiveness in terms of shelf life, decay loss, and quality of fruit. In addition to exploring post-harvest strategies, this paper provides preharvest recommendations for farmers, emphasizing methods to enhance fruit quality and longevity through effective pre-storage practices. Our IoT-based approach introduces off-season grafting in polyhouses and advanced monitoring for post-harvest storage. The results are promising: We achieved grafting success rates of 91% for acid lime and 92% for local mandarin orange varieties. Additionally, our research compared different post-harvest storage methods for mandarin oranges, including room, cellar, and cold chamber. We assessed these methods based on shelf life, physiological weight loss, and the total soluble solids (TSS) to titratable acidity (TA) ratio. The cold chamber proved to be the most effective method, offering superior conditions for storing mandarin oranges. The IoT-based monitoring system played a crucial role in maintaining optimal temperature, humidity, and gas content within the cold chamber, resulting in reduced post-harvest losses and extended shelf life. These findings highlight the transformative potential of IoT technology in mandarin orange cultivation and post-harvest storage.

Effects of Ripening Phase and Cultivar under Sustainable Management on Fruit Quality and Antioxidants of Sweet Cherry

Sweet cherry grown under sustainable management produces highly valuable fruits, whose quality shows important biochemical and morphological changes during ripening. Research was carried out in Iasi (Romania), with the aim to assess the quality characteristics of the sweet cherry fruits of three cultivars (Van, Andreiaș, Margonia), grown in an inner or outer position inside the tree crown, at the pre-ripening or full ripeness phase. In 2022, the colour component a* showed higher values in cv. Van and Andreias red fruits and in an inner position, whereas the components L* and b* at the full ripeness phase were highest in cv. Margonia. The dry matter and total soluble solids contents increased from the pre-ripening to the full ripeness phase and were highest in cv. Van sweet cherry fruits; the DM of fruit from the outer part of crown was higher than that of fruit from the inner part at the pre-ripening phase. The content of phenolics was the highest in cv. Margonia fruits at the pre-ripening stage and in cv. Van at the full ripeness phase and higher in the inner tree crown zones. The cultivar Margonia generally showed the highest vitamin C content in both years and development phases. The yellow fruit cv. Margonia mostly showed the highest values of chlorophyll a and b. The fruit’s content of carotene, lycopene, and anthocyanins was generally the highest in the red fruits of cv. Andreias. The examined sweet cherry cultivars showed a high variability in fruit nutritional quality and proved to be a rich source of bioactive compounds with antioxidant potential.

Effects of Ripening Phase and Cultivar under Sustainable Management on Fruit Quality and Antioxidants of Sweet Cherry

Sweet cherry grown under sustainable management produces highly valuable fruits, whose quality shows important biochemical and morphological changes during ripening. Research was carried out in Iasi (Romania), with the aim to assess the quality characteristics of the sweet cherry fruits of three cultivars (Van, Andreiaș, Margonia), grown in an inner or outer position inside the tree crown, at the pre-ripening or full ripeness phase. In 2022, the colour component a* showed higher values in cv. Van and Andreias red fruits and in an inner position, whereas the components L* and b* at the full ripeness phase were highest in cv. Margonia. The dry matter and total soluble solids contents increased from the pre-ripening to the full ripeness phase and were highest in cv. Van sweet cherry fruits; the DM of fruit from the outer part of crown was higher than that of fruit from the inner part at the pre-ripening phase. The content of phenolics was the highest in cv. Margonia fruits at the pre-ripening stage and in cv. Van at the full ripeness phase and higher in the inner tree crown zones. The cultivar Margonia generally showed the highest vitamin C content in both years and development phases. The yellow fruit cv. Margonia mostly showed the highest values of chlorophyll a and b. The fruit’s content of carotene, lycopene, and anthocyanins was generally the highest in the red fruits of cv. Andreias. The examined sweet cherry cultivars showed a high variability in fruit nutritional quality and proved to be a rich source of bioactive compounds with antioxidant potential.

Fungal community and toxigenic taxa in chestnut fruits in postharvest conditioning process and storage.

Chestnut fruit quality is affected by fungal contamination. The study of the patterns of contamination in the postharvest is crucial to individuate the critical phases and propose solutions. To understand how fungal colonization varies on fruits, the composition of mycobiota was investigated in postharvest handling and in between tissues (shell and kernel). Fungal sequences were clustered into 308 operational taxonomic units (OTUs). Biodiversity was higher in shell than kernel tissues. Results evidenced the risk of new contamination in specific phases such as the 'cold bath' and storage. Genera known as mycotoxin producers were detected in all phases. Specifically, 47 OTUs belonging to Penicillium, eight to Fusarium and two to Aspergillus genera were identified. While Fusarium spp. was sensitive to 'warm bath' phase, Penicillium spp. was largely insensitive and accumulated in storage conditions. Surprisingly, Aspergillus spp. was poorly represented. Aflatoxin, ochratoxin A, fumonisins and T-2/HT-2 detection was performed for shell and kernel, and process phases. Higher contamination was observed on shell than in kernel samples. While aflatoxins were within the European Union (EU) limits for dry fruits, Ochratoxin exceeded the EU limits. The present study represents the first report of fumonisins and T-2/HT-2 detection in chestnuts. Fungal contamination taxa is high in chestnut fruits following postharvest handling and storage. A parametrization of process phases such as the 'warm bath' is functional to reduce the risk for some taxa. For other spoilage and mycotoxigenic genera strict sanitation procedures of equipment and water must be individuated and implemented to reduce their impact. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fungal community and toxigenic taxa in chestnut fruits in postharvest conditioning process and storage.

Chestnut fruit quality is affected by fungal contamination. The study of the patterns of contamination in the postharvest is crucial to individuate the critical phases and propose solutions. To understand how fungal colonization varies on fruits, the composition of mycobiota was investigated in postharvest handling and in between tissues (shell and kernel). Fungal sequences were clustered into 308 operational taxonomic units (OTUs). Biodiversity was higher in shell than kernel tissues. Results evidenced the risk of new contamination in specific phases such as the 'cold bath' and storage. Genera known as mycotoxin producers were detected in all phases. Specifically, 47 OTUs belonging to Penicillium, eight to Fusarium and two to Aspergillus genera were identified. While Fusarium spp. was sensitive to 'warm bath' phase, Penicillium spp. was largely insensitive and accumulated in storage conditions. Surprisingly, Aspergillus spp. was poorly represented. Aflatoxin, ochratoxin A, fumonisins and T-2/HT-2 detection was performed for shell and kernel, and process phases. Higher contamination was observed on shell than in kernel samples. While aflatoxins were within the European Union (EU) limits for dry fruits, Ochratoxin exceeded the EU limits. The present study represents the first report of fumonisins and T-2/HT-2 detection in chestnuts. Fungal contamination taxa is high in chestnut fruits following postharvest handling and storage. A parametrization of process phases such as the 'warm bath' is functional to reduce the risk for some taxa. For other spoilage and mycotoxigenic genera strict sanitation procedures of equipment and water must be individuated and implemented to reduce their impact. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Edible coatings on postharvest quality of cherry tomatoes grown in organic and conventional systems

Cherry tomatoes belong to a promising new group of table cultivars, but show significant post-harvest quality losses, which can be reduced with edible coatings use, considered eco-sustainable. In view of the high perishability of tomatoes, the aim of this research was to evaluate the effect of different edible coatings on the shelf life of cherry tomatoes, cultivar Sweet Heaven, under organic and conventional cultivation. The experiment was conducted at the Instituto Federal Goiano, Campus Morrinhos, GO, Brazil, and the treatments were composed of coatings of chitosan, cassava starch, lactic acid and control (no coating). The samples were stored at a room with environment external temperature (± 27°C) for 20 days, arranged in a completely randomized design, with three replications. Every 2 days, the following were evaluated: fresh mass loss and moisture; pH, titratable acidity, soluble solids, lycopene, reducing sugar, vitamin C and ash; and molds and yeasts. Data were submitted to ANOVA and Tukey’s test (p<0.05). The organic system promoted greater shelf life and fruit quality of cherry tomatoes, compared to the conventional. The coating with chitosan provided longer shelf life of organic cherry tomatoes, compared to the other coatings studied, being a strong ally in reducing post-harvest waste and increasing the commercial value of the organic product, with economic strengthening for producers and traders, in addition to reduction of damage to the environment. Under conventional cultivation, the evaluated coatings were not efficient in increasing the shelf life of cherry tomatoes, requiring further studies for this condition.

A gibberellin-assisted study of the transcriptional and hormonal changes occurring at floral transition in peach buds (Prunus persica L. Batsch)

BackgroundFlower load in peach is an important determinant of final fruit quality and is subjected to cost-effective agronomical practices, such as the thinning, to finely balance the sink-source relationships within the tree and drive the optimal amount of assimilates to the fruits. Floral transition in peach buds occurs as a result of the integration of specific environmental signals, such as light and temperature, into the endogenous pathways that induce the meristem to pass from vegetative to reproductive growth. The cross talk and integration of the different players, such as the genes and the hormones, are still partially unknown. In the present research, transcriptomics and hormone profiling were applied on bud samples at different developmental stages. A gibberellin treatment was used as a tool to identify the different phases of floral transition and characterize the bud sensitivity to gibberellins in terms of inhibition of floral transition.ResultsTreatments with gibberellins showed different efficacies and pointed out a timeframe of maximum inhibition of floral transition in peach buds. Contextually, APETALA1 gene expression was shown to be a reliable marker of gibberellin efficacy in controlling this process. RNA-Seq transcriptomic analyses allowed to identify specific genes dealing with ROS, cell cycle, T6P, floral induction control and other processes, which are correlated with the bud sensitivity to gibberellins and possibly involved in bud development during its transition to the reproductive stage. Transcriptomic data integrated with the quantification of the main bioactive hormones in the bud allowed to identify the main hormonal regulators of floral transition in peach, with a pivotal role played by endogenous gibberellins and cytokinins.ConclusionsThe peach bud undergoes different levels of receptivity to gibberellin inhibition. The stage with maximum responsiveness corresponded to a transcriptional and hormonal crossroad, involving both flowering inhibitors and inductors. Endogenous gibberellin levels increased only at the latest developmental stage, when floral transition was already partially achieved, and the bud was less sensitive to exogenous treatments. A physiological model summarizes the main findings and suggests new research ideas to improve our knowledge about floral transition in peach.

Differential Efficacy of Storage Temperature and Postharvest Treatment on Shelf Life and Quality of Avocado Fruit (Persea americana Mill.).

Avocado fruit is a rich source of phytonutrients such as vitamins, minerals, carotenoids, carbohydrates, polyphenols and unsaturated fatty acids. However, due to its climacteric nature, fruits are highly susceptible to storage temperature, resulting in poor shelf life and reduced quality. In the present study avocado fruits (Accession CHES-HA-I/I) were stored at different low temperatures (5, 9 and 12°C with 90-95% relative humidity, RH) to identify optimum low temperature for cold storage. In a further experiment, avocado fruits were treated with 1-methylcyclopropene (1-MCP, 500ppb) and chitosan (0.5%) to extend the shelf life with better fruit quality. The results showed that storage temperatures had significant effect on physiological, biochemical and antioxidant activities of fruits. Lower physiological loss in weight (PLW), reduced respiration and ethylene production, and higher carbohydrates, protein and fat content were recorded in fruits stored at 9°C as compared to 12°C. Similarly, maximum antioxidant properties in terms of free radical scavenging activity (FRSA) and ferric reducing ability of plasma (FRAP) was found in avocado fruits stored at 9°C. It was also noticed that chilling injury was developed in fruits stored under 5°C. In addition, exogenous application of 1-MCP significantly reduced respiration and ethylene production rate at 9°C and extended the shelf life up to 42days with better fruit quality and more antioxidant activities. However, chitosan treated and control fruits had shelf life up to 28 and 21days respectively, with minimum nutritional content. From this study it is concluded that a storage temperature of 9°C and 1-MCP treatment significantly enhanced the shelf life of avocado fruits with better fruit quality as compared to other storage temperatures (5 and 12°C) and postharvest treatment (chitosan).

Sanitary Problems and Trace Metals Bioaccumulation during Drip Irrigation with Treated Wastewater in Okra

Water scarcity, mainly in arid and semi-arid zones, has encouraged efforts to adopt non-conventional waters for food production and agricultural development. Treated Wastewater (TWW) is one of the most continuously produced, accessible, and inexpensive water resources, with great potential for use in irrigation. The aim of this study was to investigate the combined effect of drip irrigation methods (surface vs. subsurface at 15 cm depth) and water quality (borehole water vs. treated wastewater) on soil water content, morphological and physiological traits, and nutrient content in the plant and fruit of okra grown in the Nabeul region of north-west Tunisia, a semi-arid zone. The results indicated that Okra yield was significantly affected by water quality rather than irrigation technique. Irrigation with TWW significantly increased the Okra plant height; leaf number; total fruit/m²; final yield and leaf area compared with borehole water. Nutrient levels (Fe, Cu, Zn, and Mn) in Okra plant parts (root, stem, leaf, and fruit) were also significantly increased with TWW in subsurface drip irrigation. Apart from these increased parameters were related to better soil moisture and increased available nutrients in the root zone. In terms of bioaccumulation, apart from Ni, the elements analyzed (Zn, Mn, Cu, Pb, Co, Cd) in plant and fruits showed higher values in treated wastewater than in borehole water with fruit values exceeding the toxicity threshold for Cd and Pb. Furthermore, the increase in the content of trace metal elements analyzed in the fruit following irrigation with TWW did not affect the human Health Risk Index (HRI), which remained below 1 for all treatments. Furthermore, with regard to bacterial and fungal contamination of fruit, we note that although these parameters are significantly higher in Irrigation with TWW, they remain below the toxicity thresholds. Thus, the long-term effect and continuous monitoring of the water and fruit quality in wastewater-irrigated areas to take remedial actions for sustainable agriculture development and protect ecosystems are recommended.

Beneficial Effects of Phosphite in Arabidopsis thaliana Mediated by Activation of ABA, SA, and JA Biosynthesis and Signaling Pathways.

Phosphite (Phi) has gained attention in agriculture due to its biostimulant effect on crops. This molecule has been found to benefit plant performance by providing protection against pathogens, improving yield and fruit quality as well as nutrient and water use efficiency. It is still unclear how Phi enhances plant growth and protects against multiple stresses. It has been hypothesized that Phi acts by directly affecting the pathogens and interacting with the plant cellular components and molecular machinery to elicit defense responses. This study elucidates the mechanisms underlying Phi's beneficial effects on plants, revealing their complex interplay with fundamental signaling pathways. An RNA-seq study of Arabidopsis seedlings under optimal and limiting phosphate conditions helped us unveil Phi's role in promoting plant growth by activating the expression of the genes involved in the biosynthesis and signaling pathways associated with abscisic acid (ABA), salicylic acid (SA), and jasmonic acid (JA). The expression of ABA-related genes, known for their involvement in stress response and development regulation, is triggered by Phi treatment, contributing to enhanced resilience and growth. Simultaneously, the activation of the SA pathway, associated with defense responses, suggests Phi's potential in bolstering plant immunity. Moreover, Phi influences JA biosynthesis and signaling, which are crucial for defense against herbivores and pathogens, thereby strengthening plants' defenses. Our findings reveal a multifaceted mechanism through which Phi benefits Arabidopsis development. Understanding its intricate interplay with key signaling pathways opens avenues for leveraging Phi as a strategic tool to enhance plant resilience, immunity, and growth in agricultural and ecological contexts.

Beneficial Effects of Phosphite in Arabidopsis thaliana Mediated by Activation of ABA, SA, and JA Biosynthesis and Signaling Pathways

Phosphite (Phi) has gained attention in agriculture due to its biostimulant effect on crops. This molecule has been found to benefit plant performance by providing protection against pathogens, improving yield and fruit quality as well as nutrient and water use efficiency. It is still unclear how Phi enhances plant growth and protects against multiple stresses. It has been hypothesized that Phi acts by directly affecting the pathogens and interacting with the plant cellular components and molecular machinery to elicit defense responses. This study elucidates the mechanisms underlying Phi’s beneficial effects on plants, revealing their complex interplay with fundamental signaling pathways. An RNA-seq study of Arabidopsis seedlings under optimal and limiting phosphate conditions helped us unveil Phi’s role in promoting plant growth by activating the expression of the genes involved in the biosynthesis and signaling pathways associated with abscisic acid (ABA), salicylic acid (SA), and jasmonic acid (JA). The expression of ABA-related genes, known for their involvement in stress response and development regulation, is triggered by Phi treatment, contributing to enhanced resilience and growth. Simultaneously, the activation of the SA pathway, associated with defense responses, suggests Phi’s potential in bolstering plant immunity. Moreover, Phi influences JA biosynthesis and signaling, which are crucial for defense against herbivores and pathogens, thereby strengthening plants’ defenses. Our findings reveal a multifaceted mechanism through which Phi benefits Arabidopsis development. Understanding its intricate interplay with key signaling pathways opens avenues for leveraging Phi as a strategic tool to enhance plant resilience, immunity, and growth in agricultural and ecological contexts.

Improvement of soil health and leaf nutrient status in strawberry (Fragaria × ananassa) using bioorganic formulations

In strawberry cultivation, a variety of factors influence production and fruit quality. Yield is the most crucial component in fruit production. Chemical fertilizers are typically used to boost yields, however because of their high production costs, negative effects on the environment and human health, organic fertilizers or natural amendments are being utilized instead of chemical fertilizers. The primary goals of substituting chemical fertilizers with bioorganic formulations made from natural sources for fruit production are to lower costs of production and maintain fruit production sustainability. Therefore, to study the impact of these bioorganic formulations the current investigations were conducted in open field conditions under sub humid mid hills conditions of Himachal Pradesh with 12 treatment combinations and three replicate plots. The tested plants were given various combinations of bioorganic formulations [Jeevamrit (JE) and Ghanjeevamrit (GHA)] as a source of nutrients. When compared to conventional practices, statistically significant improvements were discovered in the parameters of yield and nutrient content in the soil and plant. Significant higher yield (21.13 tonnes/ha), soil nutrients and total microbial content was recorded in T4. The results of this study provide support to the recommendation that bioorganic formulations, such as the tested ones, be used on their own or in combination as a substitute for chemical fertilizers in plant nutrition for the production of strawberries.

Physicochemical Characterization and Nutrient Composition Decide Harvest Maturity of Cucumis melo Varieties

Cucumis melo is a polymorphic taxon belonging to the family Cucurbitaceae, with several varieties based on ovary pubescence. Cucumis melo var. momordica and Cucumis melo var. acidulus are popularized and highly cultivated forms in South India. The characteristic of C.melo var.momordica is its fruit-cracking nature, which distinguishes the variety from others when it is ready to harvest. So, it would be a herculean task for the farmers to harvest ripened fruits before it gets cracked. Analysis of the ripening process's physicochemical attributes and nutritional composition is inevitable to understand and establish proper harvest management for the varieties. The current study was conducted in the experimental field of the Department of Botany, University of Kerala using two different melon varieties, Cucumis melo var. momordica (Roxb.) Duthie & Fuller (Snap melon) and Cucumis melo var. acidulus L. Naudin (culinary melon), from January to October 2021. Fruits were harvested at five developmental stages (S1: 5 days after pollination (DAP), S2: 10 DAP, S3:15 DAP, S4: 20 DAP, S5: 25 DAP) and analysed for physical and biochemical characters. Results were analyzed statistically by using one way ANOVA (P≤0.05). Pomological characteristics such as fruit weight and length at different developmental stages showed a tremendous peak from S3 to S5 in both varieties. However, the firmness of the fruits decreased from the S4 to S5 stage in varieties, reducing sugar accumulated sharply from the S2 to S3 stage. Titratable acidity content in Cucumis melo fruits continuously increased from the S1 to S5 stage. On the other hand, the total carbohydrate, cellulose, protein, and amino acid content increased from S1 to S2 but decreased sharply in S3 and S5. Ascorbic acid, total phenolics, lipid peroxidation, and electrolyte leakage levels declined with fruit ripening in Cucumis melo varieties. As a result of all the quality parameters mentioned above, Cucumis melo fruit harvested at the S4 maturity stage was the ideal harvest maturity for long-distance transportation and had higher consumer acceptability before fruit cracking. Our findings showed that the physical-biochemical properties and nutritional composition of Cucumis melo varieties change dynamically during ripening. The study highlighted the significance of maturity stages for fruit quality and provided critical information for optimal harvest management of the fruits of Cucumis melo varieties.

Physicochemical Characterization and Nutrient Composition Decide Harvest Maturity of Cucumis melo Varieties

Cucumis melo is a polymorphic taxon belonging to the family Cucurbitaceae, with several varieties based on ovary pubescence. Cucumis melo var. momordica and Cucumis melo var. acidulus are popularized and highly cultivated forms in South India. The characteristic of C.melo var.momordica is its fruit-cracking nature, which distinguishes the variety from others when it is ready to harvest. So, it would be a herculean task for the farmers to harvest ripened fruits before it gets cracked. Analysis of the ripening process's physicochemical attributes and nutritional composition is inevitable to understand and establish proper harvest management for the varieties. The current study was conducted in the experimental field of the Department of Botany, University of Kerala using two different melon varieties, Cucumis melo var. momordica (Roxb.) Duthie & Fuller (Snap melon) and Cucumis melo var. acidulus L. Naudin (culinary melon), from January to October 2021. Fruits were harvested at five developmental stages (S1: 5 days after pollination (DAP), S2: 10 DAP, S3:15 DAP, S4: 20 DAP, S5: 25 DAP) and analysed for physical and biochemical characters. Results were analyzed statistically by using one way ANOVA (P≤0.05). Pomological characteristics such as fruit weight and length at different developmental stages showed a tremendous peak from S3 to S5 in both varieties. However, the firmness of the fruits decreased from the S4 to S5 stage in varieties, reducing sugar accumulated sharply from the S2 to S3 stage. Titratable acidity content in Cucumis melo fruits continuously increased from the S1 to S5 stage. On the other hand, the total carbohydrate, cellulose, protein, and amino acid content increased from S1 to S2 but decreased sharply in S3 and S5. Ascorbic acid, total phenolics, lipid peroxidation, and electrolyte leakage levels declined with fruit ripening in Cucumis melo varieties. As a result of all the quality parameters mentioned above, Cucumis melo fruit harvested at the S4 maturity stage was the ideal harvest maturity for long-distance transportation and had higher consumer acceptability before fruit cracking. Our findings showed that the physical-biochemical properties and nutritional composition of Cucumis melo varieties change dynamically during ripening. The study highlighted the significance of maturity stages for fruit quality and provided critical information for optimal harvest management of the fruits of Cucumis melo varieties.

Variation in Soluble Sugars in Arabica Coffee Cherry Fruits.

The maturation of Arabica coffee fruits is influenced by both endogenous and external factors. The stage of fruit maturation affects the chemical composition of the beans, which in turn impacts the quality of the coffee beverage. During maturation, the fruit peel changes colour from green to red (cherry), signalling the optimal harvest time and suggesting high fruit quality. However, the degree of redness can vary, indicating different levels of maturity. This study aimed to explore the variation in soluble sugar accumulation in relation to the redness of coffee fruit tissues. We classified ripe fruits into six ripeness categories based on the intensity of the red colour of the epicarp, measured using a colourimeter. We analysed total soluble sugar, sucrose, and starch in three parts: coat (exocarp + mesocarp), coat juice (obtained by squeezing the coat), and beans. Our findings reveal that the variation in sugar in the endosperm does not correspond to changes in the coat, suggesting separate regulation of sugar accumulation, particularly sucrose, which is crucial for coffee quality. Our data indicate that there is no transfer of sucrose and reducing sugars from the red coat to the bean.

Seaweed-based biostimulants improves quality traits, postharvest disorders, and antioxidant properties of sweet cherry fruit and in response to gibberellic acid treatment

The main aim of this research was to determine whether seaweed-based biostimulants (BIO) have the potential to offset the delaying of fruit maturation and improve fruit quality and antioxidant properties in gibberellic acid (GA3)-treated cherries. Compared to the control, 5 g L−1 BIO applied twice at pit hardening (PH) and straw color (SC) or 3 times at PH, SC, and 1 week before harvest (1WBH) in mid-maturing ‘Bing’ cherries accelerated color development, increased soluble solids content (SSC), titratable acidity, total phenolics (TP), and DPPH radical scavenging activity at harvest. However, these treatments resulted in smaller and softer fruit. For late-maturing ‘Lapins’ cherries, BIO had no effect on fruit coloration, but increased the levels of antioxidants and antioxidant capacity at harvest, especially in 3 applications. Spraying 5 g L−1 BIO 3 times plus a single application of 10 mg L−1 GA3 at PH on ‘Bing’ cherries effectively increased fruit firmness (FF) and size, but showed a strong delaying effect on color development and SSC at harvest, and reduced resistance to disorders after 4 weeks of storage at 0°C if the combination-treated fruit were late harvested. Decreasing GA3 concentration from 10 to 5 mg L−1, increasing BIO concentration from 5 to 10 g L−1, and extending the harvest date by 5 d could impair the delaying effect of GA3 on fruit maturation, restore the normal fruit size, reduce the rates of decay, stem browning (SB), and surface pitting (SP), and maintain high FF and DPPH radical scavenging activity. In conclusion, pre-harvest 3 applications of 10 g L−1 BIO and 5 mg L−1 GA3 once at PH have the potential to curtail the GA3’s inhibition on fruit maturation, extend the harvest window, improve fruit quality, and increase antioxidants and antioxidant capacity in ‘Bing’ cherries.

Diurnal High Temperatures Affect the Physiological Performance and Fruit Quality of Highbush Blueberry (Vaccinium corymbosum L.) cv. Legacy

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 (Pn) by 45% and stomatal conductance (gs) 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, Pn 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.

Diurnal High Temperatures Affect the Physiological Performance and Fruit Quality of Highbush Blueberry (Vaccinium corymbosum L.) cv. Legacy.

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 (Pn) by 45% and stomatal conductance (gs) 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, Pn 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.