Peel Color Research Articles

Effect of supplemental irrigation timing and potassium fertilizer on rain-fed fig in micro-catchment: yield and yield quality

In this study, the effect of supplemental irrigation timing (treatments included no supplemental irrigation; supplemental irrigation in middle of March; supplemental irrigation in early May; supplemental irrigation in early August; and two supplemental irrigation events in middle of March and early May) and potassium (K) application (treatments included no-fertilizer; 150 and 250 g fertilizer per tree applied by fertigation method and no-fertilizer; 1.5 and 3.0 kg fertilizer per 1000 L water used by foliar application) on yield and yield quality of rain-fed fig trees were studied at the Estahban fig orchards in Fars province, Iran, through a three-year experiment. Results showed that supplemental irrigation for fig resulted in an increase in yield and fruit size, and improved the fruit peel color. However, it decreased total soluble solid of fruit. For one irrigation during the growing season, irrigation in late winter (March) with 1250 L of applied water per tree was better than irrigation in spring (May) with a similar amount applied water which was used as the supplemental irrigation of rain-fed fig trees under severe drought conditions. Two irrigation in March and May with 1500 L and 1250 L of applied water per tree for each event for the first year and two subsequent years, respectively, was more effective on the yield and fruit quality than single irrigation due to higher applied irrigation water. Using 150 g K per tree by fertigation method or 3.0 kg/1000L foliar K fertilizer resulted in significant effect on the yield and yield quality of fig and improved them.

Tree Physiology, Fruit Growth and Nutrient Elements of Wax Apple (Syzygium Samarangense) as Affected by Branch Bending Angle

This study was conducted to evaluate the potential effects of branch bending angle on the plant physiological characteristics, mineral nutrients accumulation and fruit quality of wax apple. Different treatments with five replicates each by Randomized Complete Block Design (RCBD) layouts were arranged in this study. All the treatments represent different branch angles which were at 5˚ (control), 20˚, 45˚, 65˚ and 85˚ from vertical axis. Leaf chlorophyll content (SPAD chlorophyll index) was significantly affected by different bending treatments at a budding stage, flowering, fruit development and after harvesting of wax apple. Total soluble solids (TSS) content in the leaves of bent branches increased significantly at before bud development, flowering, fruit ripening and after harvesting stages of wax apple trees. During fruit development and maturation stages, leaf TSS content was decreased in all bent branches. The results showed that 20˚ to 65˚ angle bent branches increase weight and firmness of fruit, fruit diameter and produced dark-coloured fruit compared to control. The results showed that 65˚ bent branches give the highest potassium (K+) and magnesium (Mg2+) content in the fruits. Higher sodium (Na+), iron (Fe2+) and calcium (Ca2+) content in fruits were found in 20˚ bent branches. There was a positive correlation between fruit TSS with Mg2+ (r = 0.70), with Na+ (r = 0.67) and with Ca2+ (0.57) content in the bent branches of wax apple. Fruit TSS content also positively correlated with firmness and peel colour of wax apple fruits. The number of fruit, fruit weight and fruit diameter of wax apple also positively correlated (weak) with leaves TSS content. It can be concluded that 20˚ to 65˚ branch bending angle are promising for enhancing plant physiology, fruit growth and quality of wax apple fruits.

Properties of Indonesian plantain cultivars during ripening and recommendation for flour ingredients

This research aims to examine the physicochemical changes in five Indonesian cultivars of plantain during the normal ripening and determine the optimal ripeness stage for flour. Cultivars 'Kapas', 'Tanduk', 'Raja Bulu', 'Siam', and 'Kepok Kuning' were selected for the research. The cultivars were stored at room temperature of 24.8–31.7 °C and relative humidity of 59.5%–99.9%. Peel colour, weight loss, pulp to peel ratio, firmness, pH, TSS, moisture content, starch, reducing sugars, and titratable acidity were evaluated. The results showed that the best unripe flour based on the starch content for 'Kapas', 'Raja Bulu', 'Tanduk', and 'Siam' cultivars was at stages 1–3 and 'Kepok Kuning' cultivar at ripening stages 1–2. On the other hand, in ripe banana flour, the best stage for 'Kepok Kuning', 'Tanduk', and 'Siam' cultivars was stage 4, for 'Raja Bulu' cultivar stages 4–5 and for 'Kapas' cultivar stages 4–7.

Fine Mapping of the “black” Peel Color in Pomegranate (Punica granatum L.) Strongly Suggests That a Mutation in the Anthocyanidin Reductase (ANR) Gene Is Responsible for the Trait

Anthocyanins are important dietary and health-promoting substances present in high quantities in the peel and arils of the pomegranate (Punica granatum L.) fruit. Yet, there is a high variation in the content of anthocyanin among different pomegranate varieties. The ‘Black’ pomegranate variety (P.G.127-28) found in Israel contains exceptionally high levels of anthocyanins in its fruit peel which can reach up to two orders of magnitude higher content as compared to that of other pomegranate varieties’ peel anthocyanins. Biochemical analysis reveals that delphinidin is highly abundant in the peel of ‘Black’ variety. The pattern of anthocyanin accumulation in the fruit peel during fruit development of ‘Black’ variety differs from that of other pomegranates. High anthocyanin levels are maintained during all developmental stages. Moreover, the accumulation of anthocyanin in the fruit peel of ‘Black’ variety is not dependent on light. Genetic analysis of an F2 population segregating for the “black” phenotype reveals that it is determined by a single recessive gene. Genetic mapping of the F2 population using single nucleotide polymorphism (SNP) markers identified few markers tightly linked to the “black” phenotype. Recombination analysis of the F2 population and F3 populations narrowed the “black” trait to an area of 178.5 kb on the draft genome sequence of pomegranate cv. ‘Dabenzi.’ A putative anthocyanidin reductase (ANR) gene is located in this area. Only pomegranate varieties displaying the “black” trait carry a base pair deletion toward the end of the gene, causing a frame shift resulting in a shorter protein. We propose that this mutation in the ANR gene is responsible for the different anthocyanin composition and high anthocyanin levels of the “black” trait in pomegranate.

Fruit Quality and Antioxidant Activities of Yellow-Skinned Apple Cultivars Coated with Natural Sucrose Monoesters

Yellow-skinned ‘Tsugaru’, ‘Summer King’, and ‘Shinano Gold’ apples (Malus × domestica Borkh.) were coated with a mixture of edible sucrose monoesters of fatty acid and ethanol that had never been applied in those apple fruits, for up to 28 days after room temperature storage (DAS) to evaluate their morphological characteristics, fruit qualities, and antioxidant concentrations. The coating treatment significantly reduced respiration rates of ‘Tsugaru’ and ‘Summer King’ apples at both 14 and 28 DAS, and ‘Shinano Gold’ at 28 DAS. The coated ‘Tsugaru’ and ‘Summer King’ apples were found in greater coverage with fragments of the sucrose esters than those of ‘Shinano Gold’, exhibiting greater skin greasiness and thickness. The coated ‘Tsugaru’ and ‘Summer King’ apples mostly maintained high fruit firmness, peel color, vitamin C, total polyphenol concentrations, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. The recent developed coating material contributed to improving shelf-life of the ‘Tsugaru’ and ‘Summer King’ apples and fruit defense systems as a novel post-harvest technology for sustainable food security.

Increasing Lignification in Translucent Disorder Aril of Mangosteen Related to the ROS Defensive Function

Mangosteen fruit has a high potential on the global fruit market, but some disorders, including translucent flesh, are major problems of fruit quality, limiting the marketability. The present study was conducted to compare physiological changes of reactive oxygen species (ROS), cellular lignification between translucent and normal aril, and elucidate the relation. Mangosteen fruits at purple peel color were collected from eastern Thailand during the middle of the rainy season of 2019. Translucent aril accumulated higher lignin content in the tissues, expressing firmer texture ten times higher than normal aril. Lignification was increased in translucent aril by 740% and 25% higher coniferyl alcohol dehydrogenase (CAD) and peroxidase (POD) activity, respectively, induced by high H2O2. Healthy aril performed higher activities of superoxide dismutase (SOD) (8.5 times) and ascorbate peroxidase (APX) (1.3 times) to those in translucent aril. Furthermore, the higher flavonoid content, ascorbic acid content, and antioxidant capacities detected in normal aril could significantly reduce oxidative stress. Although containing high antioxidant systems, healthy aril was found to accumulate higher malonaldehyde content (MDA). This study provides intensive evidence of oxidative stress and the defensive systems between normal and translucent tissues.

Genome-Wide Identification and Evolutionary Analysis of AOMT Gene Family in Pomegranate (Punica granatum)

Gene duplication is the major resource with which to generate new genes, which provide raw material for novel functions evolution. Thus, to elucidate the gene family evolution after duplication events is of vital importance. Anthocyanin O-methyltransferases (AOMTs) have been recognized as being capable of anthocyanin methylation, which increases anthocyanin diversity and stability and improves the protection of plants from environmental stress. Meanwhile, no detailed identification or genome-wide analysis of the AOMT gene family members in pomegranate (Punicagranatum) have been reported. Three published pomegranate genome sequences offer substantial resources with which to explore gene evolution based on the whole genome. Altogether, 58 identified OMTs from pomegranate and five other species were divided into the AOMT group and the OMT group, according to their phylogenetic tree and AOMTs derived from OMTs. AOMTs in the same subclade have a similar gene structure and protein conserved motifs. The PgAOMT family evolved and expanded primarily via whole-genome duplication (WGD) and tandem duplication. PgAOMTs expression pattern in peel and aril development by qRT-PCR verification indicated that PgAOMTs had tissue-specific patterns. The main fates of AOMTs were neo- or non-functionalization after duplication events. High expression genes of PgOMT04 and PgOMT09 were speculated to contribute to “Taishanhong” pomegranate’s bright red peel color. Finally, we integrated the above analysis in order to infer the evolutionary scenario of AOMT family.

Expression of Structural Flavonoid Biosynthesis Genes in Dark-Blue and White Myrtle Berries (Myrtus communis L.)

Within the myrtle (Myrtus communis L.) species, different genotypes may produce dark-blue berries or white berries depending on the peel color upon ripening. One dark-blue cultivar and one white myrtle cultivar were used to study the molecular mechanisms underlying flavonoid biosynthesis. The relative expression levels of common (PAL, CHS, CHI, DFR and LDOX) and specific (FLS, ANR, LAR and UFGT) flavonoid genes were analyzed during fruit development by means of quantitative real-time polymerase chain reaction (RT-qPCR). Moreover, the anthocyanin content was determined, and it showed an increase with the ripening of the berries of the dark-blue cultivar. The results showed an increased transcript abundance of PAL, CHI, DFR, LDOX and UFGT gene expression in the dark-blue cultivar compared to the white one, as well as a strong positive correlation between the changes in gene expression and anthocyanin accumulation. The transcript levels of UFGT showed sharp increases at 150 and 180 days after full blooming (DAF) in the dark-blue cultivar, which corresponded with anthocyanin accumulation. However, ripening seemed to modulate the expression of genes implicated in flavonols (i.e., FLS) and flavan-3-ols (i.e., LAR and ANR) in different manners. However, whereas FLS transcript accumulation increased at the end of the ripening period in the dark-blue cultivar, LAR and ANR gene expression decreased in both cultivars.

Distinguishing three Dragon fruit (Hylocereus spp.) species grown in Andaman and Nicobar Islands of India using morphological, biochemical and molecular traits

Dragon fruit (Hylocereus spp.), an important tropical fruit belonging to the family Cactaceae, is rich in essential nutrients such as vitamins, minerals, complex carbohydrates, dietary fibres and antioxidants. This study aims to distinguish three dragon fruit species well adapted to Andaman and Nicobar Island through morphological (34 quantitative and 26 qualitative traits), biochemical (5 traits) and molecular (14 ISSR primers) characterization. Morphological characterization revealed that presence of considerable amount of genetic variations among them especially for fruit characters viz., colour of peel and pulp. Cladode characters such as number of spines (3–5), length of areoles (mm) as 1–4, margin ribs of cladode (convex or concave) and its waxiness (weak or strong white waxy or light waxy) could be used for identification of three Hylocereus spp. under present study. Highest co-efficient of variation (%) obtained for pulp weight (88.7), whereas, lowest in distance of anthers belowstigma (3.3). Fruit and pulp weight (g) ranged from 26.5–419.3 and 10.3–258.8 with mean value of 204.8 and 125.3, respectively. Comparatively, high phenol (71.3–161.3) and flavonoid (26.6–508.2) content observed in peels than pulp (32.5–130.0 and 45.0–258.2) of fruit indicating higher antioxidant potential. Highest total carotenoids (µg 100 g−1), β-carotene (µg 100 g−1) and xanthophyll (µg g−1) content obtained in pulp on DGF3 (33.8), DGF4 (55.9) and DGF3 (32.7), whereas, in peel on DGF2 (24.3), DGF4 (18.5) and DGF2 (24.1), respectively. DPPH-based scavenging activity (%) revealed higher scavenging activity of peels (55.6–81.2) than pulp (36.0–75.3) extracts. Comparatively, ABTS-based scavenging activity (%) was found more than DPPH-based one. Sixteen ISSR primers screened, 14 were produced 178 reproducible amplified bands. Number of amplified bands varied from 5 in UBC887 to 19 in UBC811 with an average of 12.71 bands per primer. Range of polymorphic bands and % polymorphism observed were 1–13 and 20.0–92.8, respectively. The polymorphic information content value of ISSR marker ranged from 0.42 (UBC895) to 0.91 (UBC 856). Cluster analysis distinguished three different Hylocereus species on the basis of geographic origin and pulp colour by forming separate groups and two genotypes each showed 52% (DGF1 and DGF3) and 76% (DGF2 and DGF4) genetic similarity. Key traits identified for distinguishing three different Hylocereus species were: Pulp/ peel colour of fruits, number of spines and length of areoles in cladode. Genotypes with high carotenoid and xanthophylls content (DGF4 and DGF2) identified under present study may be of industrial importance for development of nutraceutical products to meet out the vitamin-A deficiency among humans in tropical regions needed future focus.

SmFLS negatively regulates peel coloring of eggplant (Solanum melongena) under high temperature.

The SmFLS gene was cloned from eggplant and has an ORF of 1014bp encoding 337 amino acids. The deduced protein sequence of SmFLS was 88.07% and 84.94% identical to homologs encoded by StFLS in Solanumtuberosum and SlFLS in S.lycopersicum, respectively. SmFLS contains typical DIOX_N and 2OG-Fe (II)_Oxy functional domains, as well as five strictly conserved amino acid residues (H223, D225, H279, R289, and S291) related to FLS enzyme activity. Phylogenetic tree analysis showed that SmFLS had the closest genetic relationship with the FLS genes in potato and tomato. At a high temperature of 35°C, the expression level of SmFLS was higher than that of the control in the same period, and it reached extremely significant levels on 15DAF and 20DAF, at which the eggplant peel color became lighter accordingly. Upon overexpression of SmFLS in eggplant, the flavonol content of transformed plants was significantly higher than that of untransformed plants, and the peel color was lighter than that of the control. The results indicate that SmFLS negatively regulates eggplant peel coloration under high temperature.

Biocontrol of Cladosporium cladosporioides of mango fruit with Bacillus atrophaeus TE7 and effects on storage quality.

The purpose of this study was to evaluate the control effect of Bacillus atrophaeus TE7 on Cladosporium cladosporioides of mango fruit and how it effects quality attributes during 'Tainong' mango fruit storage. The results showed that strain TE7 had inhibition ability with the biocontrol efficacy of 85.56%. Furthermore, strain TE7 could produce lipopeptide substance, iturin A, and surfactants, which inhibited the growth and development of C. cladosporioides. Moreover, strain TE7 had the ability of improving the activities of defense response-related enzyme in mangoes. The changes of peel color, flesh firmness, contents of total soluble solids (TSS), titratable acid (TA), and ascorbic acid (Vc) were significantly delayed by strain TE7. The results demonstrated that B. atrophaeus TE7 could be applied as a biocontrol agent for the pathogen C. cladosporioides of mango fruit.

Peel colour and flesh phenolic compounds at ripening stages in pollinated commercial varieties of fig (Ficus carica L.) fruit grown in Southern Europe

Fig fruit phenolics are beneficial to human health and contribute to attractiveness by consumers. Phenolic compounds, total carotenoids (TCAR) and total antioxidant capacity (TAC) in the flesh and chlorophylls, anthocyanins and colour in the peel were determined during ripening stages of pollinated ‘Mission’, ‘Vasilika’ and ‘Mavra Markopoulou’ (‘MM’) figs. The two latter stages studied, S3 and S4, corresponded to commercial and tree-ripe state, respectively, in each variety. Peel and flesh phenolic compounds were determined by high-performance liquid chromatography-diode array detector (HPLC–DAD). Here, the acids 2,4-dihydroxybenzoic (2,4-DHB), 2,3-dihydroxybenzoic (2,3-DHB) and sinapic, the anthocyanins delphinidin-3-O-glucoside (delph-3-glc), petunidin-O-glucoside (pt-3-glc) in flesh and malvidin-O-glucoside (malv-3-glc) in flesh and peel were revealed in figs for first time. Gallic was the prominent acid in flesh and cyanidin-O-3-rutinoside (c-3-rut) the major anthocyanin in flesh and peel in all varieties. During ripening most phenolic compounds, TCAR and TAC in flesh did not increase. Peel anthocyanins increased greatly in all varieties. The sum of anthocyanins reached 952 mg 100 g−1 fw in the dark-peel ‘MM’ at S4, corresponding to a surface colour with a hue angle value of 6.48, rendering the peel an edible part of high nutritional value. However, part of chlorophyll was still present in ‘MM’ peel. Conclusively, most of the variables determined were significantly influenced by variety and ripening stage. The hierarchical cluster analysis, a rapid and easy way of results interpretation, distinguished varieties and stages according to the variables determined, giving the opportunity for variety selection and/or ripening stage determination at harvest.

Fruit Ripening, Antioxidants and Oil Composition in Koroneiki Olives (Olea europea L.) at Different Maturity Indices

Harvest timing of oil olives is important for oil quality. Concerning the specific features of each cultivar, physiological and quality characteristics during ripening of Koroneiki olives were investigated in two successive years, A and B, from trees on full production. In A, olives were harvested at maturity indices (MIs) 0.9, 1.4, 2.1 and 4, while in B at MIs 1.1, 3.8 and 6.9. MIs ~1, ~4 and ~7 corresponded to green, red and dark purple peel in olives, respectively. Peel color parameters (L*, h° and C*), respiration and ethylene production rates were evaluated along with phenolic compounds and total antioxidant capacity (TAC) in olives of both crop years. Additionally, oil composition and a-tocopherol content were examined in olives harvested in years A and B, respectively. During fruit development, respiration and ethylene productions rates, hydroxytyrosol concentration and linoleic acid increased, while TAC, oleuropein, luteolin-7-O-glucoside, linolenic acid and α-tocopherol values decreased. Positive correlations were found among the attributes determined in both crop years that had a similar course of change during ripening, and vice versa, which could be also related to harvest timing and to quality traits of olive products. At MI ~4, at least all determined variables corresponded to oil of high quality. Practically, an early harvest might result in an olive fruit rich in antioxidants and therefore in oil production of high quality, high stability during storage and long self-life.

Extent of variability in fruit morphological characters of local mango germplasm

A study was conducted on twenty five genotypes of seedling Mangoes to examine fruit morphological characters. Fruit shape of the evaluated germplasm varied enormously and fruits of obovoid, elliptic, round and oblong shapes were found. Fruit apex shape in the evaluated plants was round, acute and obtuse. Depth of fruit stalk cavity was either absent, shallow and of medium type, whereas, fruit neck prominence was absent to slightly prominent in the tested plants. Shape of fruit ventral shoulder was varied and found to be slopping abruptly, rising and then rounded and long curve type in the evaluated germplasm. Fruit beak varies from pointed to perceptible type and fruit sinus was absent to shallow type in the fruits from different plants. Fruit attractiveness varies from very good to excellent and fruit colour from greenish yellow to green colour of fruit skin at maturity was noted in fruits from selected trees. Peel colour of AA-15 was different amongst all the genotypes which were green with red blush. Pulp colour varied from light orange, yellow orange, orange yellow, yellow and light yellow, whereas, pulp texture was soft to intermediate in the evaluated germplasm. Key words: Mangifera indica; Genotype susceptibility; Punjab; India.

Effect of growth regulators and micronutrients spray on physico-chemical properties of litchi (Litchi chinensis)

The experiment was conducted to find out the effect of plant growth regulator and micronutrients on physico-chemical properties of litchi (Litchi chinensis Sonn.) at the Regional Horticulture Research and Training Station, Dhaulakuan, Dr. Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan, dring 2014–15. The experiment consisted of 19 treatments with three replications laid out in Randomized Block Design. The growth regulators and micronutrients applied were GA3 (Tj = 25 ppm, T2 = 50 ppm, T3 = 75 ppm), CPPU (T4 = 5 ppm, T5 = 10 ppm, T6 = 15 ppm), ZnSO4 (T7 = 0.25%, T8 = 0.50%, T9 = 0.75%), boric acid (T10 = 0.25%, T11 = 0.50%, T12 = 0.75%), GA3 + CPPU (T13 = 25+5 ppm, T14 = 50+5 ppm, T15 = 75+5 ppm), Boric acid + ZnSO4 (T16 = 0.25+0.50%, T17 = 0.50+0.50%, T18 = 0.75+0.50%) and T19 the control. The growth regulators and micronutrients significantly improved all physico-chemical properties (fruit size, fruit weight, fruit volume, fruit pulp content, pulp percentage, minimum peel percentage, pulp: peel ratio, pulp: stone ratio, peel colour and juice percentage) of fruit. Of which T2 (GA3 50 ppm) increased fruit size, fruit weight and volumes, Minimum peel percentage, pulp: peel ratio and peel colour were highly affected by boric acid alone or in combination with ZnSO4.

A Squid-Detected NMR Relaxation Study of Banana Fruit Ripening

HighlightsMeasurements of relaxation times in intact banana at micro-Tesla field was achieved.Bulk spin-spin relaxation time highly correlated with best descriptors of banana ripening.A basis for quasi-continuous distribution of spin-spin relaxation in banana was given.Abstract. Achieving fast, low-cost, and non-destructive internal quality testing techniques in the horticultural industry is a challenge. Developing techniques such as ultra-low field nuclear magnetic resonance (NMR) is a promising solution. Banana is a fast ripening fruit, which undergoes many changes in quality characteristics during ripening, and was chosen as a fit choice for extensive fruit quality study by NMR. A commercial NMR system using a superconducting quantum interference device (SQUID) as a sensor and operating at 100µT was used to measure changes that occurred in banana fruit during ripening. The longitudinal and transverse relaxation times (T1 and T2, respectively), were measured on fruit samples progressively drawn from a larger batch under storage. Physico-chemical attributes such as total soluble solids (TSS), titratable acidity (TA), pH, and color parameters were measured and used as reference measurements. Statistical analysis using cross-correlation, linear regression, analysis of variance (ANOVA), and principal components analysis (PCA) were performed to probe the relationships between various quality attributes. T1 showed high correlations with total soluble solids (R = 0.84), sugar:acid ratio (R = 0.84) and color parameters (R from 0.49 to 0.88). T2, on the other hand, was most highly correlated to pH (R = 0.76) but also had a statistically significant but negative correlation with Ri (-0.58 at p <0.05). PCA results separated the first day from the remaining days of the ripening process and the overall variation was mostly explained by color attributes (a* and h), T1, TSS, and TSS/TA. During seven days of ripening in storage, the trend of change in the peel color of banana was best described by L*, a*, h and total color difference (TCD). The index of ripening, Ri, defined based on the apparent change in peel color was highly correlated to TSS, TSS/TA, L*, a*, h, TCD, and T1. The strong similarity between the evolution of T1 and the most commonly approved characteristics of banana ripening suggest that T1 has great potential for characterizing the ripening process of banana. However, an investigation of the full metabolic profile of banana during ripening would provide an understanding of the link between NMR relaxation and ripening characteristics. A distribution of T1 relaxation time of intact banana fruit at the micro-Tesla field was successfully generated using Laplace inversion. A suitable framework of T1-domain based studies on banana ripening also applicable to other fruit was discussed; it would provide a comprehensive understanding of structural changes and water mobility that occur in ripening banana. The SQUID-detected ultra-low field NMR used here shows promise as a tool for probing the quality of intact banana fruit. Keywords: Banana quality, Laplace inversion, Relaxometry, SQUID-NMR.

Transcriptome analysis reveals light-induced anthocyanin synthesis candidate genes in rabbiteye blueberry (Vaccinium ashei: Reade)

Peel colour is an important economic trait in blueberries (Vaccinium spp.) and is determined by the composition and concentration of anthocyanins. Anthocyanin accumulation within the blueberry peel is significantly affected by light. In the present study, the response mechanism of blueberry anthocyanin synthesis to various light intensities was explored in an effort to identify candidate genes involved in anthocyanin content changes using transcriptomic analysis. The analysis results indicated that a total of 671 differential genes were found, including 53 transcription factors. Among the 16 gene families of the anthocyanin synthesis pathway, 428 genes have certain expression. A total of 6,004 transcription factors in blueberry were identified following the analysis, and divided into 58 transcription factor families of which the largest was the MYB family (510). Co-expression analysis of transcription factors and anthocyanin synthesis pathway genes revealed that 36 genes (16 families) in the anthocyanin synthesis pathway are co-expressed with 66 transcription factors. The quantitative real-time polymerase chain reaction analysis results were consistent with the transcriptomic results. Six of these genes likely play an important role in the anthocyanin synthesis pathway, and further evaluation of these candidate genes is necessary. This study provides a foundation for further research on the mechanism of light-induced anthocyanin synthesis in blueberry. Supplemental data for this article is available online at https://doi.org/10.1080/13102818.2021.1924078 .

Fertigation in citrus, a toolkit for sustainable quality production

Techniques and managements of perennial fruits production are nowadays directed towards the need to conserve resources, energy and a commitment to the environment. In this sense, fertigation has risen as a valuable tool in recent years spreading around the world in major fruit belts. The million dollar question strikes why fertigation out-performs conventional basin method of irrigation carrying fertilizers. Citrus trees do not exhibit visible symptoms of water stress until most of the available soil moisture has been depleted. However, fruit set can be adversely affected at soil moisture depletion levels of only 40 to 50 percent, particularly from pre-bloom through June. Consequently, extensive research in the citrus production areas has led to the recommendation that water be applied at one-third depletion during January through June and at two-thirds depletion over the remainder of the year.Fertigation is an effective method of fertilizing in arid climates. Fertilizer levels in the soil are maintained at constant levels of 35–60 mg/kg throughout the irrigation period. Studies suggest that optimum nitrogen rate for mature Shamouti orange trees is about 170kg/ha/year. Higher nitrogen (N) rates increased yields but decreased external fruit quality by delaying peel color development and increasing peel thickness. However, juice quality, specifically total soluble solids, was not affected by nitrogen rate.A plant exposed to uniform regime of moisture and nutrient flow within rhizosphere zone has to spend much less energy than the growing conditions constantly changing over time. Fertigation, is thus, energy efficient as well. While addressing these concerns, however, the major concern emerges as orchard efficiency vis-a-vis FUE/WUE by adopting variable rate fertilizer application taking into consideration the spatial variability in soil properties in a time domain manner known as automated fertigation.This has led to an increase in both fertilizer use efficiency (FUE) and water use efficiency (WUE).

Rancang Bangun Purwarupa Sistem Deteksi Tingkat Kematangan Buah Jeruk Berdasarkan Warna Kulitnya

The process of selecting the level of maturity of an orange fruit can be done electronically, using a color sensor that will detect the color of the orange peel. Orange fruits will be grouped into two levels of maturity, namely unripe/raw and ripe. By using image processing techniques, the image of orange fruit to be selected is searched for components R (Red), G (Green), and B (Blue). If an average RGB value of less than 100 is categorized as mature and if more than 100 is categorized as immature/raw. The test results show that this system can work well as planned.

Fruit quality and antioxidant potential of Prunus humilis Bunge accessions.

In this study, we aimed to evaluate the fruit quality of Prunus humilis and identify cultivars that could provide superior human health benefits. We measured the basic characteristics, bioactive compounds, and antioxidant capacities of 137 P. humilis accessions. Flavonoid and phenol content were determined via colorimetry and ultrahigh performance liquid chromatography. Single fruit and stone weights varied widely and were genetically diverse among accessions. The variation in soluble solid content was comparatively narrow. Total flavonoid content (TFC) ranged from 3.90 to 28.37 mg/g FW, with an average of 10.58 mg/g FW in 2019. Significant differences between accessions in terms of TFC, total phenol content, and antioxidant capacity were found. TFC in the accessions was normally distributed and predominantly in the medium range (9.57-15.23 mg/g FW). Red was the predominant peel color over all other phenotypes (i.e., dark red, red, light red, red-orange, and yellow). There was no obvious correlation between peel color and TFC. Catechin was the major flavonoid component in the fruit. Principal component analysis showed that TFC, ABTS, single fruit weight, and vertical and horizontal diameter contributed to the first two principal components for each accession. Accessions 10-02, 3-17-2, 3-17-4, and JD1-6-7-37 were characterized by high TFC, ABTS, and large fruit. We believe that our results will aid in the breeding and functional food processing of Prunus humilis.