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Anthocyanin and chlorophyll content during poinsettia bract development

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Abstract

The concentration of anthocyanins, chlorophyll a and b were quantified during bract development of three differently colored Euphorbia pulcherrima Willd. cultivars ('Mars White', 'Mars Pink', and 'Mira Red') and bract color was colorimetrically determined. Color parameter a* increased from the first analyzed stage of bract development to the subsequent stages in all poinsettia cultivars. Chlorophyll a predominated over chlorophyll b in partially pigmented bracts and a sharp decrease in chlorophyll a content was detected in fully pigmented bracts. Eleven different anthocyanic pigments were identified with the use of high-performance liquid chromatography/mass spectrometry (HPLC/MS). The predominant cyanidin-3-galactoside, cyanidin-3-glucoside, cyanidin-3-rutinoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside were also detected in white and pink poinsettia bracts. Anthocyanin content levels increased significantly with the transition from partially to fully pigmented bracts in all analyzed cultivars and their accumulation coincided with the arrest of photosynthetic pigments synthesis.

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... Anthocyanins can impart the full spectrum of red hues to poinsettia bracts, from orange, red, rosy and, pink to crimson. In the most common red poinsettias, cyanidin type anthocyanins (two hydroxy groups in B-ring) are prevalent, but pelargonidin type anthocyanins (one hydroxy group in the B-ring) are also present to some extent [6] (Fig. 1a). Even traces of the delphinidin type pigments (three hydroxy groups in B-ring), have been previously found in poinsettia [6]. ...
... In the most common red poinsettias, cyanidin type anthocyanins (two hydroxy groups in B-ring) are prevalent, but pelargonidin type anthocyanins (one hydroxy group in the B-ring) are also present to some extent [6] (Fig. 1a). Even traces of the delphinidin type pigments (three hydroxy groups in B-ring), have been previously found in poinsettia [6]. The hydroxylation pattern of the B-ring of the dihydroflavonol precursors ultimately determines the anthocyanin type that is accumulated. ...
... 'Premium Red' (Additional file 2: Table S2). LC-MS analysis was performed as previously described [6] using a mass spectrometer (LCQ Deca XP MAX, Thermo Scientific) with electrospray ionization (ESI) operating in positive ion mode using MS 2 scanning mode from m/z 115 to 900. ...
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Background: Commercially available poinsettia (Euphorbia pulcherrima) varieties prevalently accumulate cyanidin derivatives and show intense red coloration. Orange-red bract color is less common. We investigated four cultivars displaying four different red hues with respect to selected enzymes and genes of the anthocyanin pathway, putatively determining the color hue. Results: Red hues correlated with anthocyanin composition and concentration and showed common dark red coloration in cultivars 'Christmas Beauty' and 'Christmas Feeling' where cyanidin derivatives were prevalent. In contrast, orange-red bract color is based on the prevalent presence of pelargonidin derivatives that comprised 85% of the total anthocyanin content in cv. 'Premium Red' and 96% in cv. 'Harvest Orange' (synonym: 'Orange Spice'). cDNA clones of flavonoid 3'-hydroxylase (F3'H) and dihydroflavonol 4-reductase (DFR) were isolated from the four varieties, and functional activity and substrate specificity of the corresponding recombinant enzymes were studied. Kinetic studies demonstrated that poinsettia DFRs prefer dihydromyricetin and dihydroquercetin over dihydrokaempferol, and thus, favor the formation of cyanidin over pelargonidin. Whereas the F3'H cDNA clones of cultivars 'Christmas Beauty', 'Christmas Feeling', and 'Premium Red' encoded functionally active enzymes, the F3'H cDNA clone of cv. 'Harvest Orange' contained an insertion of 28 bases, which is partly a duplication of 20 bases found close to the insertion site. This causes a frameshift mutation with a premature stop codon after nucleotide 132 and, therefore, a non-functional enzyme. Heterozygosity of the F3'H was demonstrated in this cultivar, but only the mutated allele was expressed in the bracts. No correlation between F3'H-expression and the color hue could be observed in the four species. Conclusions: Rare orange-red poinsettia hues caused by pelargonidin based anthocyanins can be achieved by different mechanisms. F3'H is a critical step in the establishment of orange red poinsettia color. Although poinsettia DFR shows a low substrate specificity for dihydrokaempferol, sufficient precursor for pelargonidin formation is available in planta, in the absence of F3'H activity.
... Flower color is one of the chief features of ornamental plants, and it is shaped by their biochemistry, specifically the distribution and composition of secondary metabolites in plastids and vacuoles (Zhao and Tao, 2015). Anthocyanins, carotenoids, chlorophylls, and flavonols are the major contributors to astonishing color diversity of flowers, and their content often changes during flower senescence (Schmitzer et al., 2010;Slatnar et al., 2013;Sood and Nagar, 2003). Moreover, petal structure, pH level of the cell sap, copigmentation with other phenolics, and metal ions define the color tone of various ornamentals (Cunja et al., 2014;Eugster and Markifischer, 1991). ...
... Extraction of individual anthocyanins and flavonols was performed according to the method of Slatnar et al. (2013) with some modifications. About 0.3 g of powdered petal segments were extracted with 2 mL methanol containing 3% (v/v) formic acid and 1% (w/v) 2,6-di-tert-butyl-4methylphenol (BHT) in an ultrasonic bath for 1 h. ...
... The level of total chlorophyll in the CT was comparable with the levels detected in developing bracts of several poinsettia (Euphorbia pulcherrima) cultivars (Slatnar et al., 2013), and € Unal et al. (2003) previously measured considerable levels of total chlorophyll in corolla and pedicel of P. vulgaris. The perianth of most flowering plants contains low amounts of chlorophyll and performs photosynthesis. ...
Article
Detailed anthocyanin and flavonol profiles were investigated in three flower segments of four different hybrid primrose (Primula ×polyantha) cultivars, and individual compounds were identified using high-performance liquid chromatography (HPLC)/mass spectrometry system. Chlorophyll a and b and total carotenoids were evaluated spectrophotometrically in the corolla tube (CT), and distal and proximal flower segments, and the color of each segment was assessed with a colorimeter. Chlorophyll b predominated over chlorophyll a in all flower segments, and the highest total chlorophyll levels were found in the CTs. Sixteen different anthocyanins (glycosides of cyanidin, delphinidin, peonidin, petunidin, malvidin, and rosinidin) were identified in red, pink, and blue flower extracts. Distal segments of the red hybrid and proximal segments of the pink hybrid accumulated highest levels of total anthocyanins, and no red pigments were detected in yellow-flowered hybrid primrose. Six groups of flavonols (40 individual compounds in total) were detected in different flower segments of four hybrid primrose cultivars. Yellow primrose was characterized by the greatest diversity of flavonols as it contained four isorhamnetin, five kaempferol, six laricitrin, three myricetin, six quercetin, and six syringetin glycosides. On the other hand, the smallest variety of flavonols was detected in pink hybrids. Total phenolic content (TPC) was lowest in the CT (yellow > red > pink), significantly higher in the proximal flower segment (yellow > red > pink), and highest in the distal part of the primrose petal (yellow > pink > red).
... The combination of anthocyanin and/or carotenoid, or betalains alone can be attributed to the flower colouration in the range of yellow, orange-red to red as reported in the genera Euphorbia sp. (Slatnar et al., 2013), Rosa sp. (Schmitzer et al., 2010), and Gerbera sp. ...
... Study on pigment contents during the inflorescence development had been reported in several important ornamental species like poinsettia (Slatnar et al., 2013), rose (Dela et al., 2003;Schmitzer et al., 2010), orchid (Tatsuzawa et al., 2010), daisy (Meng et al., 2004), and petunia (Moscovici et al., 1996) and found that anthocyanin biosynthesis and pigmentation are regulated by environmental stresses and flower developmental stage (Martin and Gerats, 1993). The effect of transient high temperature and progression of flower development on the concentration and composition of anthocyanins in rose petals have been previously reported (Dela et al., 2003;Schmitzer et al., 2010). ...
... In general, chlorophyll pigments for both cultivars started to decrease after four weeks of development during the early stage of fully pigmented bracts. The result is in agreement with the findings of Kannangara and Hansson (1998) and Slatnar et al. (2013) for chlorophyll accumulation during the bracts development of poinsettia. Similarly, significant decrease of total chlorophyll pigments was also observed in the early stage of bract pigmentation of poinsettia (Slatnar et al., 2013). ...
Article
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The pigment composition and colouration of inflorescence bracts of Calathea crotalifera were evaluated in this study. The concentration of anthocyanin and chlorophyll were quantified during bract development in two selected cultivars (Red and Yellow). The results of this study indicate that the concentration of different pigments (chlorophyll a and b, carotenoids and anthocyanins) varied according to bract maturity stage. The photosynthetic pigments of chlorophylls were increased at the early stage of inflorescence development and significantly decreased during the fully pigmented stage simultaneous with an increase in either carotenoids or anthocyanins. The chlorophyll contents start to increase when the inflorescence showed a discolouration of red and yellow pigments in the bracts. The major pigments in the fully pigmented yellow bract were carotenoids while the main composition pigments in red bracts were anthocyanins and carotenoids. In the investigation of shading treatments, we found that shading significantly reduced chlorophylls, carotenoids and anthocyanins contents in the bracts. The highest pigment contents were recorded in the control treatment (without shading) followed by shading at 40% and 80%. Relatively, control treatment gave the best result for growth and development of C. crotalifera cv. ‘Red’ inflorescence in terms of colour, number and size of bract, and inflorescence yield. The inflorescence length, diameter and colouration decreased significantly in shading treatments (40% and 80%) as compared with control. Overall, these works highlight the positive effects of control treatments on the development and quality of cut flowers of C. crotalifera under tropical climate in Malaysia.
... The data was collected after two months cultured and analyzed based on the percentage of necrotic leaves and concentration of chlorophyll pigments in the leave. Method for pigment identification proposed by Slatnar et al. [10] with a few modifications was used in the present study. For chlorophyll pigment analysis, leaf disc with 1 cm 2 area was mashed in 1 mL DMSO with addition of calcium carbonate powder in the 1.5 mL microtube. ...
... The samples were fixed in 2% aqueous osmium tetroxide, OsO 4 for overnight at 4°C. The treated samples were rinsed with distilled water for two times at 15 minutes each prior to dehydration through ethanol series (10,20,30,40,50,60,70,80,95, and 100%). The samples were then infiltrated through ethanol, acetone mixture at 15 minutes each, and ended with pure acetone for 1 hour before dried using a Critical Point CO 2 Dryer. ...
Chapter
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A successful protocol was established for micropropagation in two selected varieties of exotic ornamental plants, Calathea crotalifera. The effects of different sterilization techniques, explant type, and the combination and concentration of plant growth regulators on shoots induction were studied. The axillary shoot buds explants sprouted from rhizomes in soil free conditions showed high induction rate of shoots with lowest contamination percentage when treated with combination of 30% (v/v) NaOCl, 70% (v/v) ethanol, and 0.3% (w/v) HgCl 2. In the present study, the highest number of multiple shoots was obtained in MS basal medium supplemented with 3.5 mg/L 6-Benzylaminopurine (BAP), 1.0 mg/L 1-Naphthaleneacetic acid (NAA), 3% sucrose, and 6 g/L plant agar for both varieties and was used as multiplication medium. Microshoots were highly induced when the young shoot bud explants were incised longitudinally prior subculture. Chlorophyll analysis was studied to test the effects of activated charcoal and L-glutamine on reduction of necrosis problem. The maximum roots induction was recorded on MS medium supplemented with 1.0 mg/L 1-Naphthaleneacetic acid (NAA) compared to indolebutyric acid (IBA). The complete regenerated plantlets were successfully acclimatized in the soilless medium under greenhouse condition. This is the first report of rapid mass propagation for C. crotalifera.
... Moreover, it is important to note that, due to the lack of an available genome, poinsettia specific transcripts might not have been identified and, therefore, a higher number of transcripts might be involved in the flavonoid pathway. The expression of several flavonoidrelated genes found in our transcriptome, as well as previous metabolite profiling studies [30,68], implies that poinsettia bract pigmentation is achieved through the regulation of those genes and further accumulation of flavonoid compounds. ...
... During the bract development process in poinsettia, especially between stages 2 and 3, several photosynthesis related pathways showed a down-regulation in the latest stage, followed by an up-regulation of phenylpropanoid related pathways (Table 4). Increased anthocyanin content levels were detected in the transition from partially to fully pigmented poinsettia bracts, which was accompanied by the reduction of photosynthetic pigments [7,68]. Moreover, accumulation of chlorophyll was reduced when young poinsettia leaves started to accumulate anthocyanins under short day conditions, which was due to a decrease in the activity of enzymes related to chlorophyll synthesis [36]. ...
Article
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Background: Poinsettia is a popular and important ornamental crop, mostly during the Christmas season. Its bract coloration ranges from pink/red to creamy/white shades. Despite its ornamental value, there is a lack of knowledge about the genetics and molecular biology of poinsettia, especially on the mechanisms of color formation. We performed an RNA-Seq analysis in order to shed light on the transcriptome of poinsettia bracts. Moreover, we analyzed the transcriptome differences of red- and white-bracted poinsettia varieties during bract development and coloration. For the assembly of a bract transcriptome, two paired-end cDNA libraries from a red and white poinsettia pair were sequenced with the Illumina technology, and one library from a red-bracted variety was used for PacBio sequencing. Both short and long reads were assembled using a hybrid de novo strategy. Samples of red- and white-bracted poinsettias were sequenced and comparatively analyzed in three color developmental stages in order to understand the mechanisms of color formation and accumulation in the species. Results: The final transcriptome contains 288,524 contigs, with 33% showing confident protein annotation against the TAIR10 database. The BUSCO pipeline, which is based on near-universal orthologous gene groups, was applied to assess the transcriptome completeness. From a total of 1440 BUSCO groups searched, 77% were categorized as complete (41% as single-copy and 36% as duplicated), 10% as fragmented and 13% as missing BUSCOs. The gene expression comparison between red and white varieties of poinsettia showed a differential regulation of the flavonoid biosynthesis pathway only at particular stages of bract development. An initial impairment of the flavonoid pathway early in the color accumulation process for the white poinsettia variety was observed, but these differences were no longer present in the subsequent stages of bract development. Nonetheless, GSTF11 and UGT79B10 showed a lower expression in the last stage of bract development for the white variety and, therefore, are potential candidates for further studies on poinsettia coloration. Conclusions: In summary, this transcriptome analysis provides a valuable foundation for further studies on poinsettia, such as plant breeding and genetics, and highlights crucial information on the molecular mechanism of color formation.
... The data was collected after two months cultured and analyzed based on the percentage of necrotic leaves and concentration of chlorophyll pigments in the leave. Method for pigment identification proposed by Slatnar et al. [10] with a few modifications was used in the present study. For chlorophyll pigment analysis, leaf disc with 1 cm 2 area was mashed in 1 mL DMSO with addition of calcium carbonate powder in the 1.5 mL microtube. ...
... The leaf disc with 0.25 cm 2 area from the in vitro and in vivo grown plantlets was used to compare the morphological development of the leaf surface and leaf stomata from two different conditions. The samples were fixed in 2% aqueous osmium tetroxide, OsO 4 for overnight at 4 ∘ C. The treated samples were rinsed with distilled water for two times at 15 minutes each prior to dehydration through ethanol series (10,20,30,40,50, 60, 70, 80, 95, and 100%). The samples were then infiltrated through ethanol, acetone mixture at 15 minutes each, and ended with pure acetone for 1 hour before dried using a Critical Point CO 2 Dryer. ...
Article
Full-text available
A successful protocol was established for micropropagation in two selected varieties of exotic ornamental plants, Calathea crotalifera . The effects of different sterilization techniques, explant type, and the combination and concentration of plant growth regulators on shoots induction were studied. The axillary shoot buds explants sprouted from rhizomes in soil free conditions showed high induction rate of shoots with lowest contamination percentage when treated with combination of 30% (v/v) NaOCl, 70% (v/v) ethanol, and 0.3% (w/v) HgCl 2 . In the present study, the highest number of multiple shoots was obtained in MS basal medium supplemented with 3.5 mg/L 6-Benzylaminopurine (BAP), 1.0 mg/L 1-Naphthaleneacetic acid (NAA), 3% sucrose, and 6 g/L plant agar for both varieties and was used as multiplication medium. Microshoots were highly induced when the young shoot bud explants were incised longitudinally prior subculture. Chlorophyll analysis was studied to test the effects of activated charcoal and L-glutamine on reduction of necrosis problem. The maximum roots induction was recorded on MS medium supplemented with 1.0 mg/L 1-Naphthaleneacetic acid (NAA) compared to indolebutyric acid (IBA). The complete regenerated plantlets were successfully acclimatized in the soilless medium under greenhouse condition. This is the first report of rapid mass propagation for C. crotalifera .
... This is consistent with the results of a previous study. [21] Table 1. qRT-PCR quantitative primers. ...
Article
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Blueberries are particularly rich in anthocyanins and are favored extensively for their health benefits. In this study, the anthocyanin profiles of fruits of four blueberry cultivars (Gardenblue, Legacy, Misty, and Brightwell) were investigated. Total anthocyanin content gradually increased in all four cultivars during development, but mature fruits of Brightwell and Gardenblue had a higher anthocyanin content than those of Legacy and Misty. Thirty-two kinds of anthocyanins were quantified using UPLC-ESI-MS/MS. Principal component analysis showed that the anthocyanin profiles of Gardenblue and Legacy were similar to those of Misty and Brightwell, respectively. Levels of malvidin 3-O-galactoside, malvidin 3-O-glucoside, malvidin 3-O-rutinoside, delphinidin 3-O-glucoside, delphinidin 3,5-O-diglucoside(delphin), petunidin 3-O-glucoside, and petunidin 3-O-rutinoside in mature fruits of Gardenblue were higher than those in the other three cultivars. The content of delphinidin 3-O-(6”-O-malonyl)-beta-D-glucoside, petunidin 3-O-(6-O-malonyl-beta-D-glucoside), petunidin 3-O-arabinoside, delphinidin 3-O-arabinoside, and delphinidin 3-O-galactoside was the highest in mature fruits of Misty. Levels of petunidin 3,5-diglucoside and petunidin 3-O-galactoside in mature fruits of Brightwell were higher than those in the other three cultivars. Quantitative real-time reverse transcription-polymerase chain reaction analysis showed that ANS, F3ʹ5’H, and UFGT were preferentially expressed in fruits of Gardenblue, possibly attributing to higher levels of delphinidin 3-O-glucoside and delphinidin 3,5-O-diglucoside (delphin) in this cultivar. This study adds to our knowledge of anthocyanin content and profiles in the four important blueberry cultivars grown in China.
... We also found that several anthocyanins were present simultaneously in WYY and FLE, which may be because, in addition to the amount and type of total anthocyanins, the intensity of anthocyanins were affected by a variety of complex factors, such as vacuolar pH, copigmentation, and metal chelation (Manetas, 2006). The same predominant anthocyanins were found in three different colored poinsettia bracts (Slatnar et al., 2013). In our study, quercetin and kaempferol were significantly accumulated in the flavonoid synthesis pathway, which is the upstream of the anthocyanin pathway. ...
Article
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Prunus mume var. purpurea, commonly known as “Red Bone”, is a special variety with pink or purple-red xylem. It is famous due to gorgeous petals and delightful aromas, playing important roles in urban landscaping. The regulation mechanism of color formation in P. mume var. purpurea stem development is unclear. Here, we conducted a comprehensive analysis of transcriptome and metabolome in WYY (‘Wuyuyu' accession, red stem) and FLE (‘Fei Lve' accession, green stem), and found a total of 256 differential metabolites. At least 14 anthocyanins were detected in WYY, wherein cyanidin 3,5-O-diglucoside and peonidin3-O-glucoside were significantly accumulated through LC-MS/MS analysis. Transcriptome data showed that the genes related to flavonoid-anthocyanin biosynthesis pathways were significantly enriched in WYY. The ratio of dihydroflavonol 4-reductase (DFR) and flavonol synthase (FLS) expression levels may affect metabolic balance in WYY, suggesting a vital role in xylem color formation. In addition, several transcription factors were up-regulated, which may be the key factors contributing to transcriptional changes in anthocyanin synthesis. Overall, the results provide a reference for further research on the molecular mechanism of xylem color regulation in P. mume and lay a theoretical foundation for cultivating new varieties.
... The pigments responsible for poinsettia bract colouration, at least for the red hues, are the anthocyanins, a wellknown group of secondary metabolites (Stewart et al. 1979;Slatnar et al. 2013). Two main types of anthocyanins can be distinguished in poinsettia, based on the number of hydroxyl groups in the B-ring, the pelargonidin type (one hydroxyl group) and the cyanidin type (two hydroxyl groups). ...
Article
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The CRISPR/Cas9 system is a remarkably promising tool for targeted gene mutagenesis, and becoming ever more popular for modification of ornamental plants. In this study we performed the knockout of flavonoid 3'-hydroxylase (F3'H) with application of CRISPR/Cas9 in the red flowering poinsettia (Euphorbia pulcherrima) cultivar 'Christmas Eve', in order to obtain plants with orange bract colour, which accumulate prevalently pelargonidin. F3'H is an enzyme that is necessary for formation of cyanidin type anthocyanins, which are responsible for the red colour of poinsettia bracts. Even though F3'H was not completely inactivated, the bract colour of transgenic plants changed from vivid red (RHS 45B) to vivid reddish orange (RHS 33A), and cyanidin levels decreased significantly compared with the wild type. In the genetically modified plants, an increased ratio of pelargonidin to cyanidin was observed. By cloning and expression of mutated proteins, the lack of F3'H activity was confirmed. This confirms that a loss of function mutation in the poinsettia F3'H gene is sufficient for obtaining poinsettia with orange bract colour. This is the first report of successful use of CRISPR/Cas9 for genome editing in poinsettia. Supplementary information: The online version contains supplementary material available at 10.1007/s11240-021-02103-5.
... Anthocyanins have been identified as the main pigments in poinsettia bracts (Moustaka et al., 2018;Nitarska et al., 2018;Slatnar et al., 2013;Stewart et al., 1980), but extensive molecular studies of colour formation and accumulation remain lacking for this species. Dihydroflavonol-4-reductase (DFR) was suggested to promote the conversion of green leaves into red bracts (Gu et al., 2018). ...
Article
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Poinsettia is an economically important ornamental potted plant in which certain bract colour variants are often obtained by mutation breeding. Previously, in poinsettia, we identified Bract1, a GST gene involved in the sequestration and transport of anthocyanins to the vacuole. This gene carries a short, highly mutable 4‐bp repeat in its coding region. Loss of one repeat unit leads to a loss of function for Bract1, and in homozygous mutants, anthocyanin‐based coloration is absent, resulting in white or cream‐coloured bracts. Although mutation induction through ionizing radiation leads to a high frequency of mutations in Bract1, mutants are difficult to obtain from homozygous red genotypes. In this study, we used Bract1‐specific amplicon sequencing as a tool to identify mutations in pools of tissues, which enabled the detection of mutations in dilutions of up to one mutant in 50 nonmutated samples. This approach enabled efficient screening of recalcitrant homozygous genotypes for mutated alleles and the reduction of the mutation load in the application of ionizing radiation in mutation breeding programmes.
... Therefore, green leaves and red bracts occur concomitantly and accumulate different groups of pigments, i.e., chlorophylls and anthocyanins [53,61]. Several anthocyanin types have been identified in poinsettia bracts and are responsible for its colouration range [3,55,66]; however, molecular information is still limited for the species [28,72]. Nonetheless, genes responsible for the biosynthesis of the anthocyanin pathway have been intensively characterized in a range of species, with its regulation being highly dependent on R2R3-MYB regulatory genes and MYB-bHLH-WD40 (MBW) regulatory complexes [16,58,76]. ...
Article
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Background Mutation breeding is an extraordinary tool in plant breeding to increase the genetic variability, where mutations in anthocyanin biosynthesis are targets to generate distinctive phenotypes in ornamental species. In poinsettia, ionizing radiation is routinely applied in breeding programs to obtaining a range of colours, with nearly all pink and white varieties being obtained after γ- or X-ray mutagenesis of red varieties. In the present study we performed a thorough characterization of a potential mutagenesis target gene as the main responsible for the ‘ white paradox ’ in poinsettia. Results We identified a GST gene in poinsettia ( Bract1 ) as an essential factor for the expression of anthocyanin-based red colouration of bracts, which presents a high phylogenetic similarity to known anthocyanin-related GSTs. Red poinsettia varieties and white mutants generated from these varieties by X-ray were analysed for polymorphisms related to the ‘ white paradox ’ in the species. A 4 bp mutation in a short repeat within the coding region of Bract1 is most likely responsible for the appearance of white phenotypes upon irradiation treatment. The polymorphism between wild-type and mutant alleles co-segregates with the phenotype in progeny from heterozygous red and white parents. Moreover, overexpression of Bract1 wild-type allele in Arabidopsis tt19 mutants restored the anthocyanin phenotype, while the Bract1 mutated allele showed to be non-functional. Conclusions The identified repeat seems to be highly unstable, since mutated plants can be easily detected among fewer than 200 shoots derived from 10 mutated plants. Our data indicate that particular short repeat sequences, similar to microsatellite sequences or so-called dynamic mutations, might be hot spots for genetic variability. Moreover, the identification of the Bract1 mutation fills a gap on the understanding on the molecular mechanism of colour formation in poinsettia.
... Therefore, green leaves and red bracts occur concomitantly and accumulate different groups of pigments, i.e., chlorophylls and anthocyanins (Pomar and Ros Barceló, 2007;Moustaka et al., 2018). Several anthocyanin types have been identi ed in poinsettia bracts and are responsible for its colouration range (Asen, 1958;Slatnar et al., 2013;Nitarska et al., 2018); however, molecular information is still limited for the species (Gu et al., 2018;Vilperte et al., 2019). Nonetheless, genes responsible for the biosynthesis of the anthocyanin pathway have been intensively characterized in a range of species, with its regulation being highly dependent on R2R3-MYB regulatory genes and MYB-bHLH-WD40 (MBW) regulatory complexes (Dubos et al., 2010;Petroni and Tonelli, 2011;Zhao and Tao, 2015). ...
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Background: Mutation breeding is an extraordinary tool in plant breeding to increase the genetic variability, where mutations in anthocyanin biosynthesis are targets to generate distinctive phenotypes in ornamental species. In poinsettia, ionizing radiation is routinely applied in breeding programs to obtaining a range of colours, with nearly all pink and white varieties being obtained after γ- or X-ray mutagenesis of red varieties. In the present study we performed a thorough characterization of a potential mutagenesis target gene as the main responsible for the ‘white paradox’ in poinsettia Results: We identified a GST gene in poinsettia (Bract1) as an essential factor for the expression of anthocyanin-based red colouration of bracts, which presents a high phylogenetic similarity to known anthocyanin-related GSTs. Red poinsettia varieties and white mutants generated from these varieties by X-ray were analysed for polymorphisms related to the ‘white paradox’ in the species. A 4 bp mutation in a short repeat within the coding region of Bract1 is most likely responsible for the appearance of white phenotypes upon irradiation treatment. The polymorphism between wild-type and mutant alleles co-segregates with the phenotype in progeny from heterozygous red and white parents. Moreover, overexpression of Bract1 wild-type allele in Arabidopsis tt19 mutants restored the anthocyanin phenotype, while the Bract1 mutated allele showed to be non-functional. Conclusions: The identified repeat seems to be highly unstable, since mutated plants can be easily detected among fewer than 200 shoots derived from 10 mutated plants. Our data indicate that particular short repeat sequences, similar to microsatellite sequences or so-called dynamic mutations, might be hot spots for genetic variability. Moreover, the identification of the Bract1 mutation fills a gap on the understanding on the molecular mechanism of colour formation in poinsettia
... The composition of anthocyanins in LRA was analyzed by HPLC-MS and presented in Table 1. LRA was composed of six kinds of anthocyanins, including pelargonidin- [39][40][41][42]. Notably, dimmermalvidin-3-O-glucoside-petunidin-3-O-glucoside was the major anthocyanin in LRA. ...
Article
Lycium ruthenicum Murr. is a functional food with abundant anthocyanins. Since anthocyanins can change colors under different pH conditions, pH-sensitive packaging films were developed based on cassava starch and L. ruthenicum anthocyanins (LRA). Effect of LRA content on the physical, structural, antioxidant and pH-sensitive properties of starch-LRA films were evaluated. In addition, starch-LRA films were applied to monitor the freshness of pork. Spectroscopic analysis showed LRA contained six kinds of anthocyanins. The incorporation of LRA significantly enhanced the water vapor and ultraviolet-visible light barrier ability, tensile strength and antioxidant potential of starch film. Moreover, the barrier, antioxidant and pH-sensitive properties of starch-LRA films were closely related with LRA content. However, the thermal stability of starch film was not affected by LRA. Fourier transform infrared and X-ray diffraction analyses revealed intermolecular interactions (hydrogen bonds)formed between starch and LRA in the films. Starch-LRA films are pH-sensitive and could change their colors in different buffer solutions (pH 2–13). When applied to monitor the freshness of pork, starch-LRA films exhibited remarkable color variations with the quality change of pork. Our results suggested starch-LRA films could be used as active and intelligent packaging films in food industry.
... Meanwhile, anthocyanins also served as antioxidants due to their structural features. Slatnar, Mikulic-Petkovsek, Veberic, Stampar, and Schmitzer (2013) reported that the synthesis of anthocyanins was possible only with the onset of Chl degradation, indicating that a close relationship might exist between Chl metabolism and anthocyanin synthesis. Previous studies identified more than twenty-five numbers of anthocyanins from different cultivars of strawberries (Bodelón et al., 2010;Lopes Da Silva et al., 2007;Lopes-da-Silva et al., 2002). ...
Article
Colour is an important quality attribute for the consumer’s acceptability of fruit. Elevated CO2 was applied to strawberry fruit to explore its influence on chlorophyll catabolism and anthocyanin synthesis. The results showed that 20% CO2 delayed the changes of a* and b* values in strawberry fruit. The degradation of chlorophyll was delayed in CO2 treated fruit by inhibiting the activities of chlorophyllase and down-regulating the expression of FaChl b reductase, FaPAO and FaRCCR. In addition, lower concentration of anthocyanins and lower activity of PAL, C4H, 4CL and CHS were recorded under the effect of 20% CO2. Meanwhile, qRT-PCR analysis showed that 13 genes involved in the phenylpropanoid pathway and the flavonoid biosynthesis pathway were also down-regulated under CO2 stress. However, no residual effect on pigment metabolism was observed when elevated CO2 was removed. Our study provided new insights into the regulation of elevated CO2 in the role of pigment metabolism in postharvest. Keywords: Elevated CO2Strawberry fruitChlorophyll catabolismAnthocyanin synthesis
... The ratio of Chl and carotenoids or anthocyanins determines the fruit color. Studies have shown that the biosynthesis of carotenoids or anthocyanins is possible only with the onset of Chl degradation (Kannangara and Hansson 1998, Lightbourn et al. 2008, Slatnar et al. 2013. In litchi (Litchi chinensis Sonn.) fruit, the pink/red pericarp due to anthocyanin accumulation depends on the genotype and environmental factors (Wei et al. 2011). ...
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During litchi (Litchi chinensis Sonn.) fruits ripening, two major physiological changes, degreening (chlorophyll degradation) and pigmentation (anthocyanin biosynthesis) are visually apparent. However, the specific factor triggering this important transition is still unclear. In the present study, we found that endogenous ABA content increased sharply when chlorophyll (Chl) breakdown initiated and ABA level peaked just before the onset of anthocyanin accumulation, suggesting that ABA plays an important role during litchi fruit pigmentation. Then we characterized three ABSCISIC ACID RESPONSE ELEMENT-BINDING FACTORs (LcABF1/2/3) belonging to group A of basic leucine zipper (bZIP) transcription factors previously shown to be involved in ABA signaling under abiotic stress. LcABF1 transcripts increased at the onset of Chl degradation and the expression of LcABF3 accumulated in parallel with anthocyanin biosynthesis. In addition, dual luciferase assay and yeast one-hybrid system indicated that LcABF1/2 recognized ABA-responsive elements in the promoter region of Chl degradation-related genes (PAO and SGR), while LcABF2/3 bound the promoter region of LcMYB1 and anthocyanin biosynthesis-related structural genes. Indeed, Nicotiana benthamiana leaves transiently expressed LcABF1/2 showed a senescence phenomenon with Chl degradation, and LcABF3 overexpression increased the accumulation of anthocyanin via activating LcMYB1, which is the key determinant of anthocyanin biosynthesis. These data indicate that LcABF1/2/3 are important transcriptional regulators of ABA-dependent litchi fruit ripening involving in both Chl degradation as well as anthocyanin biosynthesis.
... However, to produce a blue or purple colour, a different anthocyanin, delphinidin-3-glucoside (in short: delphinidin), is possibly required. This pigment has been reported in poinsettia, but in low quantities (Slatnar et al. 2013). There have been attempts of artificially colouring the bracts to create purple, but the colour turned out to be a dirty brownish purple, which was not very attractive (Hvoslef-Eide pers. ...
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Agrobacterium-mediated transformation and transformation by electrophoresis were used in an attempt to produce poinsettias (Euphórbia Pulchérrima) with blue or purple bracts. The two methods were compared in order to determine whether one method is better suited for further transformations of poinsettia. The red poinsettia is one of the most popular Christmas plants in Norway, and creating a purple poinsettia would be of great commercial interest, as it could extend sales to the Advent season. To achieve the desired colour change, the gene coding for flavonoid 3’5’hydroxylase (F3’5’H) derived from petunia (Petunia x hybrida) was introduced. This would modify the anthocyanin pathway, potentially causing an accumulation of delphinidin, a plant pigment responsible for blueish colour in several ornamentals. The Agrobacterium-mediated transformations was tried on roughly 1500 explants. The explants were used to produce tissue cultures following the transformation, with new plants regenerated through somatic embryogenesis. Transformation by electrophoresis was used in an attempt to transform 42 shoots from 13 different plants in vivo. New shoots were derived from the putatively transformed ones, and grown in the greenhouse until bract colour developed. The Agrobacterium-mediated transformation resulted in only one completely regenerated plant within the time available for this project. Screening by PCR gave a negative result. However, several somatic embryos and shoots were still in development at the time of conclusion, and may be positive if allowed to regenerate into new plants. Transformations by electrophoresis did not result in any observed visual difference in the putatively transformed plants compared to the control plants, indicating that the transformations were so far unsuccessful. At the time of conclusion, neither method had produced poinsettias with blue or purple coloured bracts. Based on the observations made in this project, as well as previous experiments, Agrobacterium-mediated transformation seems to be the safer choice when transforming poinsettia. However, transformation by electrophoresis may be an equally efficient method for transforming poinsettia if developed further.
... Color of leaves and bracts of poinsettia is characterized by the predominance of different group of pigments: chlorophylls for green leaves and anthocyanins for red bracts (Slatnar et al., 2013). The relationship found in this paper between the typology of pot, in which the poinsettias have been grown, and the color of bract and leaves has shown that for leaves the PP container gave the best performance giving the better values of L* and a* whilst all biopots gave similar values of L*, a* and b*. ...
... However, the possible effects of AC were confounded by the decrease of photochemical efficiency when CC loss in senescing leaves of Cornus sanguinea and Parthenocissus quinquefolia (MANETAS et al., 2011). In addition, a significant decrease of photosynthetic pigments simultaneous with an increase of AC was measured in poinsettia bract development (SLATNAR et al., 2013). Due to limited information available on gene action for AC and CC in rapeseed leaf, the objective of this research were to define the gene action for AC and CC, and investigate the correlation between them for further hybrid breeding of rapeseed. ...
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Rapeseed ( Brassica napus L.) with purple-red leaf is a valuable resource for plant breeder. It was utilized in breeding program as a morphological marker, and the source of resistance gene to biotic or abiotic stress due to its anthocyanin content (AC). However, the inheritance of AC and the correlation with chlorophyll content (CC) in rapeseed leaf are still unknown. This study aimed to investigate the gene action and heritability of AC and CC in a 10-Zi006 × 10-4438 rapeseed cross using generation mean analysis. The results indicated that AC and CC were controlled by main gene effect and non-allelic interactions. The AC was mainly controlled by genetic effect. However, the genetic effect and non-genetic effect were both important for CC. In addition, the total fixable gene effects was higher than unfixable gene effects for AC, but opposite results was found for CC. Both negative and positive correlations between AC and CC were obtained in different generations.
... Color of leaves and bracts of poinsettia is characterized by the predominance of different group of pigments: chlorophylls for green leaves and anthocyanins for red bracts (Slatnar et al., 2013). The relationship found in this paper between the typology of pot, in which the poinsettias have been grown, and the color of bract and leaves has shown that for leaves the PP container gave the best performance giving the better values of L* and a* whilst all biopots gave similar values of L*, a* and b*. ...
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The poinsettias were cultivated years ago as medicinal and ornamental plants, too; but in the recent time are in the light of world flower assortment surprising with new shapes and colors in the cold season. The ornamental values of these plants are given by bracts which can have the same size as foliage leaves or even larger. The tendency of floral industry consists in obtaining high quality ornamental plants with superior marketable price. In these regards, the role of plant growth retardants in regulating the growth of poinsettia is important to obtain healthy, compact bushes and extended decoration period. The aim of the paper is to evaluate the effects of plant growth retardants on poinsettia. Five treatments with different retardants were applied as drench or spray. In the experiment four replicates and a total of 144 poinsettias were used. Treatments with paclobutrazol (60 mg/l sprayed), daminozide (2500 mg/l sprayed) and chlormequat chloride (1000 mg/l sprayed), showed the best results in case of marketability.
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Cyanidin 3-O-galactoside (Cy3Gal) is one of the most widespread anthocyanins that positively impacts the health of animals and humans. Since it is available from a wide range of natural sources, such as fruits (apples and berries in particular), substantial studies were performed to investigate its biosynthesis, chemical stability, natural occurrences and content, extraction methods, physiological functions, as well as potential applications. In this review, we focus on presenting the previous studies on the abovementioned aspects of Cy3Gal. As a conclusion, Cy3Gal shares a common biosynthesis pathway and analogous stability with other anthocyanins. Galactosyltransferase utilizing uridine diphosphate galactose (UDP-galactose) and cyanidin as substrates is unique for Cy3Gal biosynthesis. Extraction employing different methods reveals chokeberry as the most practical natural source for mass-production of this compound. The antioxidant properties and other health effects, including anti-inflammatory, anticancer, antidiabetic, anti-toxicity, cardiovascular, and nervous protective capacities, are highlighted in purified Cy3Gal and in its combination with other polyphenols. These unique properties of Cy3Gal are discussed and compared with other anthocyanins with related structure for an in-depth evaluation of its potential value as food additives or health supplement. Emphasis is laid on the description of its physiological functions confirmed via various approaches.
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The present research work was carried out at the College of Horticulture, Anantharajupeta during 2018-19. The experiment was laid out in Randomized Block Design, with three replications and with 8 genotypes. The treated rhizomes were planted under 50 per cent shadehouse condition. All the flowering, physiological attributes and anthocyanin content varied significantly among multiple heliconia genotypes grown under shadehouse conditions. Among multiple genotypes, inflorescence length (26.18 cm), number of spikes clump-1 (4.50), number of bracts spike-1 (9.56) stomatal conductance (0.38 mol m-2 s-1), rate of photosynthesis (9.23 µmol m-2 s-1), transpiration rate (4.17 mmol m-2 s-1) and anthocyanin content in flowers (3.64 mg 100 g-1 tissue) recorded highest in genotype G6. However significantly longest stalk (61.25 cm), maximum bract size (25.38 cm2) were recorded in G2 and G1, respectively. While more leaf intercellular CO2 (317.38 µmol m-2 s-1) was recorded in genotype G3.
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Poinsettia (Euphorbia pulcherrima, Willd. ex Klotzsch) originated in Mexico is an important ornamental tree in all over the world because its bract color can change from green to red under short-day conditions. In view of this, poinsettia not only has high ornamental value but also is an important model plant in studies on anthocyanin metabolism regulated by photoperiod. In this research, we compared the content of metabolic products in anthocyanin biosynthesis pathway and transcriptome sequencing data between green and red-turning bracts of poinsettia to clarify the mechanism of color change. The results of metabolic product analysis suggested that far downstream genes such as dihydroflavonol 4-reductase (DFR) gene in anthocyanin biosynthesis pathway could be inhibited in green bracts. A total of 91,917 uni-transcripts were identified through transcriptome sequencing. Seventy-two uni-transcripts were assigned to flavonoid biosynthesis pathways. Through a correlation analysis of gene expression profiles and color compound contents, DFR was taken into account as a candidate gene promoting anthocyanin accumulation in poinsettia bracts under short-day conditions. Transgenic research showed that overexpression of poinsettia DFR significantly increased the anthocyanin content in Arabidopsis (Arabidopsis thaliana). Based on these results, this research identified DFR as a promoter of anthocyanin accumulation in poinsettia bracts under short-day conditions. Moreover, the results of this research will shed light on elucidation of anthocyanin biosynthesis mechanism of plants and provide candidate genes for genetic improvement on poinsettia.
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Foliar sprays of Ca (300, 400, and 500 mg L-1), B (0.2, 0.5, and 0.8 mg L-1), Mo (0.3, 0.4, and 0.5 mg L-1), Ca + B (400 + 0.5 mg L-1), Ca + Mo (400 + 0.4 mg L-1), B + Mo (0.5 + 0.4 mg L-1) and Ca + B + Mo (400 + 0.5 + 0.4 mg L-1), were applied to improve the quality of poinsettia plants (Euphorbia pulcherrima) cv. ‘Supjibi Red’. Treatments were applied three times at: beginning, middle, and end of the short photoperiod. Calcium at 400 mg L-1 increased significantly plant height by 15.3 %. Leaf chlorophyll concentration decreased by 25% when bract pigmentation initiated. Treatments did not affect the leaf chlorophyll contents. Calcium (300 mg) and B (0.8 mg) increased the number of transitional bracts (5.7 and 5.6, respectively) compared to 0.4 mg L-1 Mo treatment; while B (0.5 mg) increased the total number of colored bracts per shoot (8.36) compared to the rest of the treatments. Total chlorophyll concentration decreased by 95 % in transitional bracts, carotenoids decreased 89 % and anthocyanins increased considerably (from 21.4 to 296.7 mg g-1). Foliar applications of calcium improved poinsettia plant height and the Ca plus B combination accelerated bract pigmentation.
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High-performance liquid chromatographic (HPLC) procedures for the separation of flavonoids in poinsettia bracts are described. Anthocyanins present were cyanidin 3-galactoside, and the 3-glucosides and 3-rutinosides of cyanidin and pelargonidin. Flavonols present were 3-rhamnosylgalactosides, 3-rhamnosylgluco-sides, 3-galactosides, 3-glucosides, and 3-rhamnosides of quercetin and kaempferol. The use of these chemical markers along with the classical methods for plant identification should help resolve the difficulties of describing new cultivars protected by the plant patent law.
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Measuring genome size by flow cytometry assumes direct proportionality between nuclear DNA staining and DNA amount. By 1997 it was recognized that secondary metabolites may affect DNA staining, thereby causing inaccuracy. Here experiments are reported with poinsettia (Euphorbia pulcherrima) with green leaves and red bracts rich in phenolics. DNA content was estimated as fluorescence of propidium iodide (PI)-stained nuclei of poinsettia and/or pea (Pisum sativum) using flow cytometry. Tissue was chopped, or two tissues co-chopped, in Galbraith buffer alone or with six concentrations of cyanidin-3-rutinoside (a cyanidin-3-rhamnoglucoside contributing to red coloration in poinsettia). There were large differences in PI staining (35-70 %) between 2C nuclei from green leaf and red bract tissue in poinsettia. These largely disappeared when pea leaflets were co-chopped with poinsettia tissue as an internal standard. However, smaller (2.8-6.9 %) differences remained, and red bracts gave significantly lower 1C genome size estimates (1.69-1.76 pg) than green leaves (1.81 pg). Chopping pea or poinsettia tissue in buffer with 0-200 microm cyanidin-3-rutinoside showed that the effects of natural inhibitors in red bracts of poinsettia on PI staining were largely reproduced in a dose-dependent way by this anthocyanin. Given their near-ubiquitous distribution, many suspected roles and known affects on DNA staining, anthocyanins are a potent, potential cause of significant error variation in genome size estimations for many plant tissues and taxa. This has important implications of wide practical and theoretical significance. When choosing genome size calibration standards it seems prudent to select materials producing little or no anthocyanin. Reviewing the literature identifies clear examples in which claims of intraspecific variation in genome size are probably artefacts caused by natural variation in anthocyanin levels or correlated with environmental factors known to induce variation in pigmentation.
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In this article we present a survey of the pigments found in the flowers and fruits of old and modern varieties of roses. The yellow colors are produced by carotenoids, the reds by anthocyanins, and the modern oranges by a mixture of the two. The great structural diversity of the carotenoids contrasts with a surprisingly small number of anthocyanins. For the carotenoids found in roses, a clear correspondence exists between the structure and the breeding partners used; the old yellow roses, which arose from crosses with Chinese varieties, mainly contain carotenoids from early stages in the biosynthesis, while in the modern yellow roses, which are descended from Central Asian foetida types, hydroxylations, epoxidations, and epoxide transformations readily occur. A recently elucidated carotenoid degradation sequence follows the scheme C40 → C13 + C27 → C13 + C14. The C13 compounds are odoriferous substances that contribute to the scent of roses. In the physiological pH region, copigmentation with flavonol glycosides is crucial for stabilization of the anthocyanin chromophores. Many roses, including the “apothecary's rose”, which was once used medicinally, contain large amounts of strongly astringent ellagitannins, monosaccharide esters of gallic acid.
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Specific absorption (α) coefficients for individual carotenoids and chlorophylls a and b, as well as the E1%1cm values for combined carotenoids, have been (re)estimated using 6 solvents (80 % acetone, chloroform, diethyl ether, dimethyl formamide, dimethyl sulphoxide, and methanol) using 2 different types of spectrophotometer (0.1—0.5 nm and 1—4 nm band pass resolution). From these values, 2 sets of equations to calculate concentrations of chlorophyll a (Ca), chlorophyll b (Cb) and total carotenoids (Cx+c) in γg mL-1 for the different instrument types were freshly derived or confirmed from earlier publications. These were then tested with 3 different types of spectrophotometers (the two variable types plus 2 nm fixed resolution diode array) using equal aliquots of a mixed extract in the 6 different solvents. These showed that the concentrations and ratios derived by the 2 sets of equations were comparable when used with their own type of spectrophotometer but less so if the inappropriate equations were used. Measurements taken with the diode array spectrophotometer, however, did not give accurate concentrations or ratios of chlorophylls and carotenoids.
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At irradiances close to those representing a sunny day, red and green leaves of poinsettia (Euphorbia pulcherrima) showed only minor differences in their photosynthetic capacities despite the strong differences in their pigment composition. However, contrarily to green leaves, red leaves did not show inhibition of photosynthesis at high irradiances, because anthocyanins protected chloroplasts from photoinhibition.
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The flower is the most significant and beautiful part of plants. Flowers are very useful organs in plant developmental phenomenon. During flower bud opening, various events takes place in a well defined sequence, representing all aspects of plant development, such as cell division, cellular differentiation, cell elongation or expansion and a wide spectrum of gene expression. The complexity of flower bud opening illustrates that various biological mechanisms are involved at different stages. Senescence represents the ultimate stage of floral development and results in wilting or abscission of whole flower or flower parts. Senescence is an active process and governed by a well defined cell death program. Once a flower bud opens, the programmed senescence of petal allows the removal of a metabolically active tissue. In leaves, this process can be reversed, but in floral tissue it cannot, indicating that a highly controlled genetic program for cell death is operating. The termination of a flower involves at least two, sometimes overlapping, mechanisms. In one, the perianth abscises before the majority of its cells initiate a cell death program. Abscission may occur before or during the mobilization of food reserves to other parts of the plant. Alternatively, the petals may be more persistent, so that cell deterioration and food remobilization occur while the petals are still part of the flower. The overall pattern of floral opening varies widely between plant genera, therefore, a number of senescence parameters have been used to group plants into somewhat arbitrary categories. Opening and senescence of rose flower is still an unsolved jigsaw in the world of floriculture industry and the mechanism behind the onset of the very early events in the sequence still remains to be elucidated. Hence, for advancing the knowledge on the pertinent aspect of bud opening and senescence the literature has been cited under this review.
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Euphorbia pulcherrima Klotz plants exposed to short days (11 h light/13 h dark) for a period of eight weeks, developed flowers and a red canopy consisting of bracts and few true leaves. Plants maintained for three weeks under short day conditions, failed to produce flower primordia or a red canopy in the following 5 weeks in continuous light. Between the 4th and 5th short day week, the youngest leaves began to accumulate anthocyanin and turned red while the apical meristems differentiated into flower primordia. Chlorophyll accumulation ceased at the onset of anthocyanin synthesis and the protein content per unit leaf area declined. mRNA for glutamyl-tRNAGlu synthetase (EC 6.1.1.17) and glutamyl-tRNAGlu reductase also declined during this period. Western blot analysis revealed a loss of glutamyl-tRNAGlu reductase, glutamate 1-semialdehyde (EC 5.4.3.8) and the Mg-chelatase subunits, Olive and CH42, in the last 2 to 4 weeks of the photoperiod.
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The correlation between the anthocyanin concentrations of seven Acer palmatum Thunb. cultivars and the chromaticity values a*, b*, a*/b* ratio, h degrees and L* was investigated. According to the position of leaves on the branch terminal, middle and base sample leaves were analyzed and the positional effect on the level of the major anthocyanin was estimated. Leaf color was measured with a portable colorimeter and individual anthocyanins were detected with the use of HPLC-MS. Cyanidin-3-glucoside was present in all senescing leaves of Acer cultivars and its content decreased from terminal to base position. Cyanidin-3-rutinoside was identified in lower concentrations in the leaves of all cultivars. Multiple variable analysis was calculated for each of the tristimulus values and two major anthocyanins (cyanidin-3-glucoside, cyanidin-3-rutinoside) in senescing leaves of ornamental Acer cultivars. Correlations were detected between the major anthocyanin (cyanidin-3-glucoside) in analyzed Acer cultivars and all chromaticity parameters. The highest correlation coefficient (0.94) was observed between cyanidin-3-glucoside and a*/b* ratio in cultivar 'Bloodgood' and lowest (0.54) between cyanidin-3-glucoside and a* in Acer palmatum Thunb. The correlation between cyanidin-3-rutinoside and chromaticity parameters was not detected in all Acer cultivars, additionally correlation coefficients and statistical significance were much lower. The expression of red color in both senescing leaves and in all-year-red cultivars can be tightly linked with the content level of cyanidin-3-glucoside: the second major anthocyanin does not contribute much to the red leaf color. (C) 2008 Elsevier B.V. All rights reserved.
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The concentration of major anthocyanins, quercetins, catechin, and phenolic acids during flower development of Rosa xhybrida L. 'KORcrisett' was quantified using high-performance liquid chromatography/mass spectrometry. Additionally, the changes in petal color were monitored colorimetrically at four different stages of development (bud, partially open flowers, fully open flowers, senescent flowers) and correlation was calculated between the chromaticity parameters and major/total anthocyanins. Color parameters a*, b*, and h degrees decreased with the progression of flower development and a*/b* ratio and lightness (L*) increased. In rose petals, a negative trend in the content of major (pelargonidin-3,5-di-O-glucoside, cyanidin-3,5-di-O-glucoside) and minor (pelargonidin-3-O-glucoside, cyanidin-3-O-glucoside, peonidin-3-O-glucoside) anthocyanins was observed during flower development. Buds contained almost threefold higher concentrations of pelargonidin-3,5-di-O-glucoside and fourfold higher concentrations of cyanidin-3,5-di-O-glucoside than senescent flowers. Buds also contained significantly more quercetins (quercetin-3-O-rutinoside, quercetin-3-O-glucoside, and quercetin-3-O-rhamnoside), catechin, and phenolic acids (gallic acid, protocatechulic acid, chlorogenic acid, caffeic acid, p-coumaric acid) than flowers of subsequent developmental stages. The most significant differences were observed in the content of gallic acid; buds contained almost sixfold higher values than senescent flowers. Correlation analysis revealed a strong correlation between chromaticity parameters a*, b*, a*/b* ratio, h degrees, L*, and major/total anthocyanins with values ranging from 0.60 to -0.84.
Article
In the present study, the chemical and morphological status of eight cultivars of groundcover rose (Rosa xhybrida) with a range of flower colors was investigated. From the methanolic extracts of rose petals collected from flowers at four developmental stages, several phenolic compounds were identified via high-performance liquid chromatography/mass spectrometry, including five anthocyanins, which are especially important for the visual attributes of rose flowers. Colorimetric parameters were also measured and correlated with total anthocyanins and cell sap pH levels. During flower development from bud to senescent stage, a significant trend was detected; lightness (L-star) increased, b(star) decreased in all analyzed roses, and a(star) decreased in pink and red cultivars. Cell sap pH level increased from bud to senescent petals; fresh weight, dry weight, and water content increased to fully open stage and were then reduced in senescent petals. Total anthocyanin and quercetin content increased from bud stage to fully open flowers, and was decreased in senescent ones. However, the highest content of total phenolics was measured in buds and partially opened flowers, respectively. Three distinct groups were formed according to the content of total anthocyanins and quercetins; white cultivars were most distant from the red ones, which were similar to the pink and light red cultivars.
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The phenolics in 20 apple cultivars comprising 19 English cider apple varieties and one dessert apple variety were analysed by high‐performance liquid chromatography/tandem mass spectrometry. The cider varieties contained higher levels than the dessert apple and the peel was richer in phenolics than the flesh. The phenolic concentrations ranged between 230 and 4920 mg kg−1 fresh weight in the flesh and between 546 and 6306 mg kg−1 fresh weight in the peel. Fifteen compounds from five different phenolic groups, flavan‐3‐ols, flavonols, anthocyanins, hydroxycinnamates and dihydrochalcones, were detected. The major components in the flesh were 5‐O‐caffeoylquinic acid, procyanidin B2 and (−)‐epicatechin, while (−)‐epicatechin and quercetin glycosides predominated in the peel. Copyright © 2007 Society of Chemical Industry