Fruit Color Development Research Articles

Identification of Grape Laccase Genes and Their Potential Role in Secondary Metabolite Synthesis.

Laccase, a copper-containing oxidoreductase, has close links with secondary metabolite biosynthesis in plants. Its activity can affect the synthesis and accumulation of secondary metabolites, thereby influencing plant growth, development, and stress resistance. This study aims to identify the grape laccases (VviLAC) gene family members in grape (Vitis vinifera L.) and explore the transcriptional regulatory network in berry development. Here, 115 VviLACs were identified and divided into seven (Type I-VII) classes. These were distributed on 17 chromosomes and out of 47 VviLACs on chromosome 18, 34 (72.34%) were involved in tandem duplication events. VviLAC1, VviLAC2, VviLAC3, and VviLAC62 were highly expressed before fruit color development, while VviLAC4, VviLAC12, VviLAC16, VviLAC18, VviLAC20, VviLAC53, VviLAC60 and VviLAC105 were highly expressed after fruit color transformation. Notably, VviLAC105 showed a significant positive correlation with important metabolites including resveratrol, resveratrol dimer, and peonidin-3-glucoside. Analysis of the transcriptional regulatory network predicted that the 12 different transcription factors target VviLACs genes. Specifically, WRKY and ERF were identified as potential transcriptional regulatory factors for VviLAC105, while Dof and MYB were identified as potential transcriptional regulatory factors for VviLAC51. This study identifies and provides basic information on the grape LAC gene family members and, in combination with transcriptome and metabolome data, predicts the upstream transcriptional regulatory network of VviLACs.

Physiological and Biochemical Effects of Intermittent Warming on 'Marmandi' Turning Tomato Fruits During Low-Temperature Storage

This experiment was conducted on the variety 'Marmandi' turning tomato fruits to investigate the effect of intermittent warming temperatures during extended low chilling temperature storage (21 days) on the subsequent ripening quality of tomato fruits. The quality was measured by assessing the quantitative amount of total phenolic compounds, chlorogenic acid, and ascorbic acid, as well as the development of fruit color and the evaluation of chilling injury (CI) symptoms. The results indicated that the amounts of total phenolic compounds and chlorogenic acid increased significantly during continuous low-temperature storage and after subsequent transfer to room temperature, with this increase being associated with significant loss of ascorbic acid. More frequent periods of intermittent warming (IW) during low-temperature storage were very effective in significantly decreasing the rate of accumulation of phenolic compounds, chlorogenic acid, and ascorbic acid losses. A significant reciprocal relationship between the amounts of chlorogenic acid and ascorbic acid was observed. Additionally, the results showed that as IW time increased, its effectiveness in retarding CI significantly improved.

Mutation of YFT3, an isomerase in the isoprenoid biosynthetic pathway, impairs its catalytic activity and carotenoid accumulation in tomato fruit.

Tomato fruit colors are directly associated with their appearance quality and nutritional value. However, tomato fruit color formation is an intricate biological process that remains elusive. In this work we characterized a tomato yellow fruited tomato 3 (yft3, e9292, Solanum lycopersicum) mutant with yellow fruits. By the map-based cloning approach, we identified a transversion mutation (A2117C) in the YFT3 gene encoding a putative isopentenyl diphosphate isomerase (SlIDI1) enzyme, which may function in the isoprenoid biosynthetic pathway by catalyzing conversion between isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). The mutated YFT3 (A2117C) (designated YFT3 allele) and the YFT3 genes did not show expression difference at protein level, and their encoded YFT3 allelic (S126R) and YFT3 proteins were both localized in plastids. However, the transcript levels of eight genes (DXR, DXS, HDR, PSY1, CRTISO, CYCB, CYP97A, and NCED) associated with carotenoid synthesis were upregulated in fruits of both yft3 and YFT3 knockout (YFT3-KO) lines at 35 and 47days post-anthesis compared with the red-fruit tomato cultivar (M82). In vitro and in vivo biochemical analyses indicated that YFT3 (S126R) possessed much lower enzymatic activities than the YFT3 protein, indicating that the S126R mutation can impair YFT3 activity. Molecular docking analysis showed that the YFT3 allele has higher ability to recruit isopentenyl pyrophosphate (IPP), but abolishes attachment of the Mg2+ cofactor to IPP, suggesting that Ser126 is a critical residue for YTF3 biochemical and physiological functions. As a result, the yft3 mutant tomato line has low carotenoid accumulation and abnormal chromoplast development, which results in yellow ripe fruits. This study provides new insights into molecular mechanisms of tomato fruit color formation and development.

Fruit Position, Light Exposure and Fruit Surface Temperature Affect Colour Expression in a Dark-Red Apple Cultivar

This study aimed to evaluate the effects of fruit position, light exposure and fruit surface temperature (FST) on apple fruit colour development and fruit quality at harvest, including sunburn damage severity. This was achieved by undertaking two experiments in a high-density planting of the dark-red apple ANABP 01 in Tatura, Australia. In the 2020–2021 growing season an experiment was conducted to draw relationships between fruit position and fruit quality parameters. Here, sample fruit position and level of light exposure were respectively determined using a static LiDAR system and a portable quantum photosynthetically active radiation (PAR) sensor. At harvest the sample fruit were analysed for percentage red colour coverage, objective colour parameters (L*, a*, b*, hue angle and chroma), sunburn damage, fruit diameter (FD), soluble solids concentration (SSC), flesh firmness (FF) and starch pattern index (SPI). A second experiment was conducted in the 2021–2022 growing season and focused on how fruit shading, light exposure and the removal of ultraviolet (UV) radiation affected the FST, colour development and harvest fruit quality. Five treatments were distributed among sample fruit: fully shaded with aluminium umbrellas, shaded for one month and then exposed to sunlight until harvest, exposed for one month and then shaded until harvest, covered with a longpass UV filter and a control treatment. The development of colour in this dark-red apple cultivar was highly responsive to aspects of fruit position, and the intensity and quality of light exposure. The best-coloured fruit were exposed to higher quantities of PAR, exposed to both PAR and UV radiation simultaneously and located higher in the tree canopy. Fruit that were fully exposed to PAR and achieved better colour development also displayed higher FST and sunburn damage severity.

Influence of Bio-stimulants on the Yield Attributes, Peel and Pulp Color of Mango (Mangifera indica L.) cv Mallika under Central Dry Zone of Karnataka

The mango (Mangifera indica L.) is considered the ‘King of fruits’ and found to be economically important due to its excellent fruit quality, despite having good fruit quality characteristics, it is associated with production constraints such as low initial fruit set, heavy fruit drops, undersized fruit and improper fruit color development. On the other hand, bio-stimulants play an important role in improving the productivity and quality of fruits. In the present study, four biostimulants viz., jasmonic acid, salicylic acid, brassinosteroids and triacontanol, were sprayed at intervals of 70 and 90 days after anthesis at two different concentrations with four replications. Among the treatments, triacontanol @ 10 ppm (T9) showed a significant difference in yield parameters and recorded maximum average fruit weight (571.98 g), fruit length (17.53 cm), fruit diameter (92.38 cm), fruit volume (723.75 cc), pulp weight (435.91 g), pulp percentage (76.24), number of fruits (75.25), yield per tree (41.31 kg) in comparison to control. However, salicylic acid @ 150 ppm (T5) showed the highest colorimeter coordinates L*, a*, b*, C* and hº for both pulp and peel color. The study concludes the use of phytohormones enhances the fruit development and quality parameters of mango cv Mallika under the central dry zone of Karnataka.

Tracing the color: quantitative trait loci analysis reveals new insights into red-flesh pigmentation in apple (Malus domestica).

Red-flesh color development in apple fruit is known to depend upon a particular allele of the MdMYB10 gene. While the anthocyanin metabolic pathway is well characterized, current genetic models do not explain the observed variations in red-flesh pigmentation intensity. Previous studies focused on total anthocyanin content as a phenotypic trait to characterize overall flesh color. While this approach led to a global understanding of the genetic mechanisms involved in color expression, it is essential to adopt a more quantitative approach, by analyzing the variations of other phenolic compound classes, in order to better understand the molecular mechanisms involved in the subtle flesh color variation and distribution. In this study, we performed pedigree-based quantitative trait loci (QTL) mapping, using the FlexQTL™ software, to decipher the genetic determinism of red-flesh color in five F1 inter-connected families segregating for the red-flesh trait. A total of 452 genotypes were evaluated for flesh color and phenolic profiles during 3years (2021-2023). We identified a total of 24 QTLs for flesh color intensity and phenolic compound profiles. Six QTLs were detected for red-flesh color on LG1, LG2, LG8, LG9, LG11, and LG16. Several genes identified in QTL confidence intervals were related to anthocyanin metabolism. Further analyses allowed us to propose a model in which the competition between anthocyanins and flavan-3-ols (monomer and oligomer) end-products is decisive for red-flesh color development. In this model, alleles favorable to high red-flesh color intensity can be inherited from both white-flesh and red-flesh parents.

FcMET1 mediates low DNA methylation and promotes peel coloring in Ficus carica

Fig (Ficus carica L.) with purple-red peel cultivars are popular among consumers and exhibit better storability. While DNA methylation influences fruit ripening and color development, its specific role in fig fruit remains unclear. This study explores the impact of DNA methylation on the fig peel coloration. Enzymatic colorimetric detection revealed that the level of ‘Purple Peel’ fig DNA methylation decreases with fig fruit ripening and coloring. Treatment of young fruit with the DNA-methylation inhibitor azacytidine induced peel coloration, suggesting that a decrease in DNA-methylation level promotes fig peel coloration. Seven members of DNA methyltransferases and three members of DNA demethylases were identified from a high-level fig genome, highlighting FcMET1 and FcDRM2 as stable proteins, ensuring functional expression. Reference to the Arabidopsis protein interaction network map predicted that FcMET1 is in a central position, suggesting a crucial regulatory role in multiple biological processes. Correlation analysis revealed a positive correlation between FcMET1 expression during peel development and the level of total DNA methylation. Weighted gene co-expression network analysis identified co-expression of FcMET1 with the color-related transcription factors MYB, bHLH and WD40, as well as with eight structural genes in the flavonoid-biosynthesis pathway. The expression of FcUFGT3 was negatively correlated with that of FcMET1. McrBC-PCR and Bisulfite Sequencing detection showed that a low methylation level of the FcUFGT3 promoter corresponds with its high expression in colored fig. This investigation of the mechanism of DNA methylation provides a theoretical basis for understanding the role of DNA-methylation modifications in fig ripening and coloring.

Metabolite profiling and hormone analysis of the synchronized exocarp-mesocarp development during ripening of cv. ‘Fuerte’ and ‘Hass’ avocado fruits

Color development in avocado fruits is a complex mechanism influenced by several factors. To understand this process, a comparative analysis was conducted between fruits of 'Fuerte' and 'Hass' avocado cultivars using metabolomic approaches. Pigment content in the exocarp differs between cultivars, accumulating anthocyanins in 'Hass' avocado. Carbohydrate abundance differed at ready-to-eat stage showing that 'Hass' accumulated higher amounts of sucrose, mannoheptulose, and perseitol than ‘Fuerte’ in both tissues. Higher amounts of fatty acids were observed in both tissues of 'Fuerte'. Polar metabolites indicated differences in amino acid and carbohydrate metabolisms between cultivars. Hormone analysis suggested that abscisic acid is involved in pigment biosynthesis. These findings showed that hormone and primary metabolites cross-talk plays an important role in color development in the exocarp and in the softening in the mesocarp of ‘Hass', opening new perspectives about this metabolic interplay and its relation to the development of the exocarp-mesocarp synchronization during ripening.

Comparative metabolomics reveals complex metabolic shifts associated with nitrogen-induced color development in mature pepper fruit.

Pigments derived from red pepper fruits are widely used in food and cosmetics as natural colorants. Nitrogen (N) is a key nutrient affecting plant growth and metabolism; however, its regulation of color-related metabolites in pepper fruit has not been fully elucidated. This study analyzed the effects of N supply (0, 250, and 400 kg N ha-1) on the growth, fruit skin color, and targeted and non-target secondary metabolites of field-grown pepper fruits at the mature red stage. Overall, 16 carotenoids were detected, of which capsanthin, zeaxanthin, and capsorubin were the dominant ones. N application at 250 kg ha-1 dramatically increased contents of red pigment capsanthin, yellow-orange zeaxanthin and β-carotene, with optimum fruit yield. A total of 290 secondary metabolites were detected and identified. The relative content of most flavonoids and phenolic acids was decreased with increasing N supply. Correlation analysis showed that color parameters were highly correlated with N application rates, carotenoids, flavonoids, phenolic acids, lignans, and coumarins. Collectively, N promoted carotenoid biosynthesis but downregulated phenylpropanoid and flavonoid biosynthesis, which together determined the spectrum of red color expression in pepper fruit. Our results provide a better understanding of the impact of N nutrition on pepper fruit color formation and related physiology, and identification of target metabolites for enhancement of nutritional quality and consumer appeal.

Sustainable Approaches to Prolonging Shelf Life in Green Mature Tomato Fruit

Green mature tomato fruits demonstrate better transportability compared to fully matured ones. This approach has the potential to play a significant role in diminishing postharvest losses and enhancing the accessibility of nutritionally rich fruit in developing countries. The instability of electricity and insufficient cold storage facilities is recognized for fading the shelf life of various fruits and vegetables. However, post-harvest interventions, including tomatoes, can extend perishable products' shelf life. Firstly, tomato fruits were harvested at the green mature stage and stored at 33℃ for 0, 10, 20, and 30 days, followed by a shift to 25℃. Subsequently, ten fruits were subjected to various treatments: A - control (25℃), B - 33℃ with 30-40% RH, C - 33℃ with 50-60% RH, and D - 33℃ with 80-90% RH. Different relative humidity (RH) levels were achieved using saturated salts, specifically MgCl2.6H2O, Mg (NO3)2.6H2O, and KCl+KNO3 for treatments B, C, and D, respectively. The evaluation encompassed parameters such as ethylene production, CO2 release, fruit firmness, weight loss, and color development. A higher temperature, such as 33℃, may be considered advantageous for the storage of green mature tomato fruit. Evidently, tomatoes were successfully stored for over 55 days at this temperature. Across all relative humidity (RH) conditions, there was more noticeable color development in fruits stored at 25°C compared to those stored at 33°C. Among the various RH conditions, fruits stored at 33°C with 80-90% RH experienced the least weight loss, although fruit firmness gradually declined over time. Storing green mature tomato fruit at 33°C with 30-40% RH resulted in the lowest ethylene production compared to 25°C and other RH conditions. Consequently, certain practical benefits of green mature tomato fruit under elevated temperatures and diverse relative humidity (RH) conditions are suggested. However, further detailed research may be necessary to explore potential metabolic changes.

Aminoethoxyvinylglycine Reduces Preharvest Fruit Drop and Fruit Ethylene Evolution in ‘Red Delicious’ Apple but Affects Fruit Size and Quality Inconsistently

Aminoethoxyvinylglycine (AVG) is widely used in commercial apple (Malus ×domestica Borkh.) production to reduce preharvest fruit drop (PFD) and delay ripening for harvest management. Recently, the maximum allowable concentration of AVG was doubled (up to 264 mg⋅L−1). Reports of the relationship between the AVG concentration and fruit growth, size, and quality have been contradictory. We evaluated the relationship between the AVG concentration and PFD, fruit size, fruit quality, and expression of ethylene signaling-related and cell wall modification-related genes. Experiments were conducted in 2019 and 2020 using mature ‘Red Delicious’ in western North Carolina. The AVG treatments [0 and 132 (AVG-1x) and 264 mg⋅L−1 (AVG-2x)] were applied 3 weeks before the expected harvest. The AVG treatments reduced fruit drop and internal ethylene concentration relative to the control in both years. There was no difference in drop between AVG-1x and AVG-2x applications. Only in 2020 did AVG treatments delay fruit softening and starch hydrolysis and reduce soluble solids concentration. There were no effects on red fruit color development. Fruit size was unaffected by AVG in 2019, but it was reduced in 2020 with the AVG-2x application. AVG reduced ethylene synthesis and altered signaling, evidenced by decreased relative expression of genes related to ethylene signaling (ARGOS1, ARGOS2). AVG applications also reduced the expression of EXPA8;1, suggesting that reduced cell wall disassembly was associated with a reduction in fruit softening. These results indicate that preharvest applications of 132 mg⋅L−1 AVG effectively reduced PFD via altering ethylene evolution and signaling. Use of a higher AVG concentration was of limited benefit.

Enhancing Red Fruit Coloration of Apples in the Southeastern US with Reflective Fabrics

For some apple cultivars, inadequate red fruit color development can reduce crop value. The use of reflective groundcovers has been demonstrated to improve red coloration in apples in other regions, but evaluation in the southeastern USA has been limited. To address this, we compared the performance of multiple reflective groundcovers in 2018 and 2020 on mature ‘Fuji’ trees in Edneyville, NC, USA. Woven reflective (Extenday® DayBright, Lumilys® WH100, Beltech PD2911, and Belton experimental), mylar, and sod groundcovers were deployed ~5 weeks before anticipated harvest. The effects of the treatment on light reflectance (photosynthetically active and UV radiation), fruit color, fruit quality, and crop value were determined. Across both years of evaluation, reflective groundcovers were consistent in increasing the reflectance of photosynthetically active radiation. However, only Extenday® DayBright consistently increased reflected UV radiation (250–400 nm), red fruit coloration at commercial harvest, and crop value. Fruit maturity and sunburn incidence were not influenced by any treatment in both years. Reflected UV light quality was not characterized, but it is clear that UV250–400nm reflectance intensity is critical to enhance ‘Fuji’ fruit color development. Growers in the southeastern US can use reflective groundcovers to enhance red fruit coloration to meet market demands.

Pigment Biosynthesis and Molecular Genetics of Fruit Color in Pepper.

Pepper, as a vegetable crop with a wide cultivation area worldwide, besides being a significant condiment and food, also has a momentous use for chemistry, medicine, and other industries. Pepper fruits are rich in various pigments, such as chlorophyll, carotenoids, anthocyanins, and capsanthin, which have important healthcare and economic value. Since various pigments are continuously metabolized during the development of pepper fruits, peppers exhibit an abundant fruit-colored phenotype in both the mature and immature periods. In recent years, great progress has been made in the study of pepper fruit color development, but the developmental mechanisms are still unclear systematically dissected in terms of pigment, biosynthesis, and regulatory genes. The article outlines the biosynthetic pathways of three important pigments: chlorophyll, anthocyanin, and carotenoid in pepper and the various enzymes involved in these pathways. The genetics and molecular regulation mechanisms of different fruit colors in immature and mature peppers were also systematically described. The objective of this review is to provide insights into the molecular mechanisms of pigments biosynthesis in pepper. This information will provide theoretical basis for the breeding of high-quality colored pepper varieties in the future.

Improving the Quality and Shelf Life of Guava Fruits Using 1-Methylcyclopropene

Storage of guava fruits by using refrigerators as post-harvest treatment is commercially acceptable but is expensive, especially in developing countries. So, the present investigation was carried out with the objective to compare the efficacy of 1-MCP and their most effective concentrations for the shelf-life enhancement of guava fruits without any deterioration in fruit quality in the winter season at both cold and room-temperature storage conditions. Horticultural mature guava fruits were treated with 150, 300, and 600 ppb, and then stored at room temperature at 21°C, RH 45%, or cold storage at 6°C, RH 85%. The Results showed that the highest concentration of 1-MCP (600ppb) significantly (P<0.05) preserved fruit firmness, and organoleptic quality attributes. In addition, the fruit weight loss, decay percentage, titratable acidity (TA), total soluble solids (TSS), and fruit color development were significantly preserved compared to other treatments under both cold and room storage conditions. Generally, 1-Methylcyclopropene (1-MCP) could maintain the quality of guava fruit combined with cold temperatures for 24 days. While 150 and 300 ppb 1-MCP preserved the quality of fruits for up to 20 days compared to untreated fruits for 16 days. Otherwise, treated fruits with 600ppb of 1-MCP kept at room storage temperature preserved fruits quality for up to 20 days compared with untreated fruits for up to 12 days stored at room storage condition. Hence, 1-MCP as post-harvest treatments preserved the overall quality parameters and enhanced the shelf life of guava fruit even after two weeks of storage at ambient temperature and three weeks after cold storage. Otherwise, 1-MCP could be an alternative to cold storage, as it is more economical than cold storage, especially in developing countries.

Study of Biochemical and Phytochemical Variations in Carica papaya, Linn. During Storage

Papaya is a tropical fruit and is usually harvested prior to the onset of climacteric rise. The moisture content of Papaya is always higher than 70% throughout the season. The moisture content increases significantly with season. The phytochemical analysis of Papaya leaves contain carbohydrates, saponins, terpenoides, alkaloids, phenols, glycosides, cardiac glycosides and flavonoids. Temperature has a major role in the post harvested biochemical changes and the activity of polyphenol oxidase in Papaya. Flesh color development in nonstored fruits did not change significantly during the first six days of storage, and then rapidly increases. Unripe fruit stored for 5 days at above 27 ºC exhibits faster ripening rates. The optimal temperature for storing Papayas are found to be between 21.5 to 25 ºC. Biochemical changes in Papaya fruits at room temperature revealed that the level of phenolics and reducing sugars are gradually increases . But there is a gradual decrease in the protein content of the fruits. As the PPO quality deteriorating enzyme, the nutritional quality was assayed by estimating the activity of PPO. The enzyme was responsible for the browning of Papaya fruits. Post harvest storage of Papaya is a major problem for many farmers. High moisture content of papaya fruit may affect the contamination of disease spreading microbes and insect vectors. They may cause spoilage of soft tissues of Papaya. High temperature storage may cause the nutrient quality of fruit. Many enzymes and proteins degraded in extreme temperature condition.

Identifikasi Penanda Masak Fisiologis untuk Panen Benih Mentimun (Cucumis sativus L.)

Identification of Physiological Cooking Markers for Cucumber (Cucumis sativus L.) Seed Harvest. Cucumber (Cucumis sativus L.) has a wide adaptability to the environment. Cucumber production in Indonesia has decreased every year. The availability of quality seeds is one of the important factors in increasing the productivity of cucumber plants. This study aims to identify physiological ripening markers, especially in cucumber fruit. This study used a one-factor randomized block design method with 4 levels of treatment at harvesting age of cucumbers, namely 24, 27, 30, and 33 days after flower blooming. The variables observed in this study were; a) identification of fruit and seed maturity markers; 1) fresh weight of fruit (g), 2) fresh weight of 100 seeds (g), 3) oven dry weight of 100 seeds (g), 4) seed moisture content (%), and 5) fruit color development; b) testing of seed quality; 1) seed germination (%) and 2) seed germination vigor (%).The results showed that the right harvest time based on the character of the fruit and seeds to produce quality seeds for cucumber plants was 27 days after the flowers bloom. The character of the fruit at that time was shiny green with a yellow tinge and reached the maximum fresh weight, while the character of the seeds at that time was bright yellow seeds, with a fresh weight of 100 seeds was 3,95g and an oven dry weight of 100 seeds was 1,51g reaching the maximum weight. And seed moisture content at the age of 27 with the lowest percentage. The quality of cucumber seeds harvested when physiologically ripe was obtained with the highest average values such as seed germination (93.17%) and simultaneous growth vigor (81.83%).

Transcriptome analysis reveals the fruit color variation in Ailanthus altissima.

Anthocyanins are responsible for the intensity of color in plants; however, the systematic mechanisms underlying the color differences in the fruit of Ailanthus altissima remain unknown. Therefore, this study aims to analyze the transcriptomes of the white and red fruit of A. altissima by screening and validating the key genes involved in flavonoid and anthocyanin biosynthesis. Samples of A. altissima fruit were collected 30, 45, and 60 days after flowering, and their pigment and sugar content were determined. The anthocyanin content was significantly higher in red than in white fruits. Transcriptome analysis was also performed on the fruit samples, 73,807 unigenes were assembled and annotated to seven databases. Twenty-one co-expressed modules were identified via weighted gene co-expression network analysis, of which two were associated with flavonoids and anthocyanins. Furthermore, in three growth stages, 126, 30, and 124 differentially expressed genes were screened between white and red fruit. Genes involved in flavonoid and anthocyanin metabolism were identified. AaDFR (A. altissima bifunctional dihydroflavonol 4-reductase/flavanone 4-reductase) and AaANS (A. altissima anthocyanidin synthase) were associated with flavonoid and anthocyanin metabolism. Members of the AaDFR and AaANS families were also identified, and their basic physicochemical characteristics, conserved domains, motif compositions, phylogenetics, and expression levels were analyzed. The overexpression of AaDFR and AaANS in transgenic Arabidopsis significantly increased the content of seed and foliar flavonoids and anthocyanins. The study elucidated the different mechanisms underlying fruit color development and provided insight into A. altissima plants breeding with commercially desirable properties.

Evolution of the Volatile Organic Compounds, Phenols and Antioxidant Capacity during Fruit Ripening and Development of Rubus ulmifolius Schott Fruits

Nowadays, a growing interest in consumers’ fruit with a high content of health-promoting compounds has been observed. In this sense, wild berries have received special attention based on their high accumulation of phenolic compounds, as well as their characteristic and pleasant aroma. In this work, we characterize the color development, antioxidant capacity, phenolic contents, and volatile profile of Rubus ulmifolius Schott fruit at different ripening stages during two seasons on the same orchard. Four stages were established based on the color parameter, which was consistent with changes in the weight and size of the fruit. In addition, total phenolic and flavonoid content showed a decrease during the fruit ripening, in contrast with the total anthocyanins content that increased at the final stages of ripening. In addition, the antioxidant capacity was evaluated through two approaches: FRAP and DPPH, which consistently displayed higher levels at the final stages in the two different seasons. Finally, the VOCs analysis showed an active synthesis of volatile compounds during the late stage of ripening, with alcohols being the most abundant compounds for each ripening stage. These results allow us to propose a classification of different ripening stages of the wild blackberry to have a better knowledge of this interesting fruit with higher healthy- and nutraceutical compounds.

Effect of Antagonistic Microorganisms on Fruit Colour Development and Sensory Properties of Papaya (Carica papaya) var. Red Lady

An experiment was conducted in the Department of Agricultural Microbiology and Post-Harvest Technology, COH, Bagalkot, Karnataka during the year 2017-2018 with intention of minimizing the post harvest diseases during storage by using ecofriendly approach that is use of biocontrol agents and their effects on fruit colour development and sensory parameters. A wide range of fungi, bacteria, yeast and actinomycetes can be used as antagonistic microorganisms against post-harvest pathogens in many horticulture produce. In the present experiment, five effective antagonistic microorganisms were assessed for their antifungal activity against Colletotrichum gleosporiodies, the causal agent of post-harvest Anthracnose disease of papaya fruits and fortheir effects on fruit development and sensory properties of papaya var. Red Lady. In the present experiment the papaya fruits treated with biocontrol agents and observed that, the papaya fruits treated with BCA5-Isolate No.10(T5) exhibited higher L*(56.53), a*(12.33), b*(43.60) colour values, higher carotene value (1.85 mg/100 g), total sugar content (11.6%) and good sensory scores for colour (8073), taste (8.6) and textue (9.03) at 9 days after storage under ambient storage condition followed by BCA-Isolate No.09(T4) and carbendazium at 0.1% for 5 min (T7). Treated on inoculated papaya fruits with C. gloeosporioides, T5 (BCA5 -Isolate No. 10) recorded higher L*(55.67), a*(11.61), b*(41.78) colour values, higher carotene value (1.42 mg/100 g), total sugar content (10.4%) and good sensory scores for colour (8.3), taste (8.13) and textue (8.73) at 9 days after storage under ambient storage condition followed by BCA4 -Isolate No.9 (T4) and carbendazium at 0.1% (T7). These two isolates identified in this experiment can be effectively used alternative to chemicals against anthracnose which were effective in fruit colour development and sensory parameters.

Comparative transcriptome profiling and molecular marker development for oil palm fruit color

Oil palm harvesting is normally determined by fruit exocarp color. To detect expressed sequence tag (EST)-simple sequence repeat (SSR) markers in oil palm hybrid populations, de novo transcriptomic profiling of Nigeria black and Suratthani 1 (Deli × Calabar) plants was performed. More than 46 million high-quality clean reads with a mean length of 1117 bp were generated. Functional annotation and gene ontology (GO) enrichment analysis of differentially expressed genes (DEGs) revealed that the genes were involved in fruit color development and pigment synthesis. Comparison of immature/mature DEGs indicated that nigrescent fruit color was driven by the anthocyanin biosynthesis pathway (ABP); however, the carotenoid biosynthesis pathway (CBP) was involved in the color development of both fruit types. The transcripts of both unique and different genes involved in the ABP and CBP in higher plants were highlighted for further study, especially 3GT, downstream genes in the ABP, and DEARF27 in the CBP. Additionally, SSR primer motifs, namely, 9949, discovered from the DEGs upregulated in the virescent type that encode vacuolar iron transporter (VIT), could separate the nigrescence and virescence traits of Nigeria hybrids. This novel primer has potential to be used as a molecular for further selection in breeding programs especially involving the specific genetic backgrounds described in this study.