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Suzy Y. Rogiers - One of the best experts on this subject based on the ideXlab platform.
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Vascular development of the grapevine (Vitis vinifera L.) inflorescence Rachis in response to flower number, plant growth regulators and defoliation.
Journal of plant research, 2017Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The grapevine inflorescence is a determinate panicle and as buds emerge, shoot, flower and Rachis development occur simultaneously. The growth and architecture of the Rachis is determined by genetic and environmental factors but here we examined the role of flower and leaf number as well as hormones on its elongation and vascular development. The consequences of Rachis morphology and vascular area on berry size and composition were also assessed. One week prior to anthesis, Merlot and Cabernet Sauvignon field vines were exposed to manual flower removal, exogenous plant growth regulators or pre-bloom leaf removal. Manual removal of half the flowers along the vertical axis of the inflorescence resulted in a shorter Rachis in both cultivars. Conversely, inflorescences treated with gibberellic acid (GA3) and the synthetic cytokinin, 6-benzylaminopurine (BAP) resulted in a longer Rachis while pre-bloom removal of all leaves on the inflorescence-bearing shoot did not alter Rachis length relative to untreated inflorescences. Across the treatments, the cross-sectional areas of the conducting xylem and phloem in the Rachis were positively correlated to Rachis girth, flower number at anthesis, bunch berry number, bunch berry fresh mass and bunch sugar content at harvest. Conversely, average berry size and sugar content were not linked to Rachis vascular area. These data indicate that the morphological and vascular development of the Rachis was more responsive to flower number and plant growth regulators than to leaf removal.
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Flowers regulate the growth and vascular development of the inflorescence Rachis in Vitis vinifera L.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The Rachis, the structural framework of the grapevine (Vitis vinifera L.) inflorescence (and subsequent bunch), consists of a main axis and one or more orders of lateral branches with the flower-bearing pedicels at their fine tips. The Rachis is crucial both for support, and transport from the shoot. Earlier suggestions that the flowers per se affect normal Rachis development are investigated further in this study. Different percentages (0, 25, 50, 75 or 100) of flowers were removed manually one week before anthesis on field-grown vines. Treatment effects on subsequent Rachis development (curvature, vitality, anatomy, starch deposit) were assessed. Sections, both fixed and embedded, and fresh hand-cut were observed by fluorescence and bright-field optics after appropriate staining. Emphasis was on measurement of changes in cross-sectional area of secondary xylem and phloem, and on maturation of fibres and periderm. Specific defects in Rachis development were dependent on the percent and location of flower removal one week prior to anthesis. The Rachises curved inwards where most of the flowers were removed. When fully de-flowered, they became progressively necrotic from the laterals back to the primary axes and from the distal to the proximal end of those axes, with a concurrent disorganisation of their anatomy. A few remaining groups of flowers prevented desiccation and abscission of the Rachis axes proximal to the group, but not distally. Flower removal (50%) reduced Rachis elongation, while 75% removal reduced xylem and phloem area and delayed phloem fibre and periderm development. 75% flower removal did not affect starch present in the Rachis during berry development. Developing flowers affect the growth and vitality of the Rachis and the development of its vascular and support structures. The extent of these effects depends on the cultivar and the number and position of flowers remaining after some are removed one week before anthesis.
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The amino acid distribution in Rachis xylem sap and phloem exudate of Vitis vinifera 'Cabernet Sauvignon' bunches.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Martin J. Canny, Suzy Y. RogiersAbstract:Amino acids are essential to grape berry and seed development and they are transferred to the reproductive structures through the phloem and xylem from various locations within the plant. The diurnal and seasonal dynamics of xylem and phloem amino acid composition in the leaf petiole and bunch Rachis of field-grown Cabernet Sauvignon are described to better understand the critical periods for amino acid import into the berry. Xylem sap was extracted by the centrifugation of excised leaf petioles and Rachises, while phloem exudate was collected by immersing these structures in an ethylenediaminetetraacetic acid (EDTA) buffer. Glutamine and glutamic acid were the predominant amino acids in the xylem sap of both grapevine Rachises and petioles, while arginine and glycine were the principal amino acids of the phloem exudate. The amino acid concentrations within the xylem sap and phloem exudate derived from these structures were greatest during anthesis and fruit set, and a second peak occurred within the Rachis phloem at the onset of ripening. The concentrations of the amino acids within the phloem and xylem sap of the Rachis were highest just prior to or after midnight while the flow of sugar through the Rachis phloem was greatest during the early afternoon. Sugar exudation rates from the Rachis was greater than that of the petiole phloem between anthesis and berry maturity. In summary, amino acid and sugar delivery through the vasculature to grape berries fluctuates over the course of the day as well as through the season and is not necessarily related to levels near the source.
Takao Komatsuda - One of the best experts on this subject based on the ideXlab platform.
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The Ectopic Expression of Btr2 in Aegilops tauschii Switches the Disarticulation Layer From Above to Below the Rachis Node.
Frontiers in plant science, 2020Co-Authors: Xiaoxue Zeng, Shinji Kikuchi, Hidenori Sassa, Akemi Tagiri, Takao KomatsudaAbstract:Seed dispersal among wild species belonging to the tribe Triticeae is typically achieved by the formation of a brittle Rachis. The trait relies on the development of a disarticulation layer, most frequently above the Rachis node (resulting in wedge type dispersal units), but in some species below the Rachis node (resulting in barrel type dispersal units). The genes responsible for the former type are the complementary pair Btr1 and Btr2, while the genetic basis of the latter type has yet to be determined. Aegilops tauschii forms barrel type dispersal units and previous study showed this species lacked an intact copy of Btr1. Here it has been demonstrated that Ae. tauschii carries two of Btr2; and that Btr2 transcript is present in a region below the Rachis node where the abscission zone forms. The implication is that in this species, the Btr2 product is involved in the formation of barrel type dispersal units.
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The unique disarticulation layer formed in the Rachis of Aegilops longissima probably results from the spatial co-expression of Btr1 and Btr2.
Annals of botany, 2020Co-Authors: Xiaoxue Zeng, Shinji Kikuchi, Hidenori Sassa, Gang Chen, Lei Wang, Akemi Tagiri, Takao KomatsudaAbstract:BACKGROUND AND AIMS The brittle Rachis trait is a feature of many wild grasses, particularly within the tribe Triticeae. Wild Hordeum and Triticum species form a disarticulation layer above the Rachis node, resulting in the production of wedge-type dispersal units. In Aegilops longissima, only one or two of the nodes in the central portion of its Rachis are brittle. In Triticeae species, the formation of a disarticulation layer above the Rachis node requires the co-transcription of the two dominant and complementary genes Btr1 and Btr2. This study aims to establish whether homologues of Btr1 and/or Btr2 underlie the unusual brittle Rachis phenotype observed in Ae. longissima. METHODS Scanning electron microscopy was used to examine the disarticulation surfaces. Quantitative RT-PCR and RNA in situ hybridization experiments were used to identify gene expression in the immature inflorescence. KEY RESULTS Analysis based on scanning electron microscopy was able to demonstrate that the disarticulation surfaces formed in the Ae. longissima Rachis are morphologically indistinguishable from those formed in the Rachises of wild Hordeum and Triticum species. RNA in situ hybridization showed that in the immature Ae. longissima inflorescence, the intensity of Btr1 transcription varied from high at the Rachis base to low at its apex, while that of Btr2 was limited to the nodes in the central to distal portion of the Rachis. CONCLUSIONS The disarticulation pattern shown by Ae. longissima results from the limitation of Btr1 and Btr2 co-expression to nodes lying in the centre of the Rachis.
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The Brittle Rachis Trait in Species Belonging to the Triticeae and Its Controlling Genes Btr1 and Btr2.
Frontiers in plant science, 2020Co-Authors: Xiaoxue Zeng, Assaf Distelfeld, Juqing Jia, Kohei Mishina, Peter Jeff Maughan, Shinji Kikuchi, Hidenori Sassa, Takao KomatsudaAbstract:In many non-cultivated angiosperm species, seed dispersal is facilitated by the shattering of the seed head at maturity; in the Triticeae tribe, to which several of the world's most important cereals belong, shattering takes the form of a disarticulation of the Rachis. The products of the genes Btr1 and Btr2 are both required for disarticulation to occur above the Rachis nodes within the genera Hordeum (barley) and Triticum/Aegilops (wheat). Here, it has been shown that both Btr1 and Btr2 are specific to the Triticeae tribe, although likely paralogs (Btr1-like and Btr2-like) are carried by the family Poaceae including Triticeae. Aegilops tauschii (the donor of the bread wheat D genome) lacks a copy of Btr1 and disarticulation in this species occurs below, rather than above the Rachis node; thus, the product of Btr1 appears to be required for disarticulation to occur above the Rachis node.
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On the Origin of the Non-brittle Rachis Trait of Domesticated Einkorn Wheat.
Frontiers in Plant Science, 2018Co-Authors: Mohammad Pourkheirandish, Benjamin Kilian, Hiroyuki Kanamori, Assaf Distelfeld, George Willcox, Taihachi Kawahara, Shun Sakuma, Takashi Matsumoto, Takao KomatsudaAbstract:Einkorn and emmer wheat together with barley were among the first cereals to be domesticated by humans more than 10,000 years ago, long before durum or bread wheat originated. Domesticated einkorn wheat differs from its wild progenitor in basic morphological characters such as the grain dispersal system. Here, we identify the brittle Rachis 1 (Btr1) and brittle Rachis 2 (Btr2) in einkorn as homologous to barley. We show that a single non-synonymous amino acid substitution (alanine to threonine) at position 119 at btr1, responsible for the non-brittle Rachis trait in domesticated einkorn. Tracing this haplotype variation back to wild einkorn samples provides further evidence that the einkorn progenitor came from the Northern Levant. We show that the geographical origin of domesticated haplotype coincides with the non-brittle domesticated barley haplotypes which suggest the non-brittle Rachis phenotypes of einkorn and barley were fixed in same geographic area in today’s South-east Turkey.
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On the Origin of the Non-brittle Rachis Trait of Domesticated Einkorn Wheat.
Frontiers in plant science, 2018Co-Authors: Mohammad Pourkheirandish, Benjamin Kilian, Hiroyuki Kanamori, Assaf Distelfeld, George Willcox, Taihachi Kawahara, Shun Sakuma, Takashi Matsumoto, Fei Dai, Takao KomatsudaAbstract:Einkorn and emmer wheat together with barley were among the first cereals domesticated by humans more than 10,000 years ago, long before durum or bread wheat originated. Domesticated einkorn wheat differs from its wild progenitor in basic morphological characters such as the grain dispersal system. This study identified the Non-brittle Rachis 1 (btr1) and Non-brittle Rachis 2 (btr2) in einkorn as homologous to barley. Re-sequencing of the Btr1 and Btr2 in a collection of 53 lines showed that a single non-synonymous amino acid substitution (alanine to threonine) at position 119 at btr1, is responsible for the non-brittle Rachis trait in domesticated einkorn. Tracing this haplotype variation back to wild einkorn samples provides further evidence that the einkorn progenitor came from the Northern Levant. We show that the geographical origin of domesticated haplotype coincides with the non-brittle domesticated barley haplotypes, which suggest the non-brittle Rachis phenotypes of einkorn and barley were fixed in same geographic area in today's South-east Turkey.
Aude M. Gourieroux - One of the best experts on this subject based on the ideXlab platform.
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Vascular development of the grapevine (Vitis vinifera L.) inflorescence Rachis in response to flower number, plant growth regulators and defoliation.
Journal of plant research, 2017Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The grapevine inflorescence is a determinate panicle and as buds emerge, shoot, flower and Rachis development occur simultaneously. The growth and architecture of the Rachis is determined by genetic and environmental factors but here we examined the role of flower and leaf number as well as hormones on its elongation and vascular development. The consequences of Rachis morphology and vascular area on berry size and composition were also assessed. One week prior to anthesis, Merlot and Cabernet Sauvignon field vines were exposed to manual flower removal, exogenous plant growth regulators or pre-bloom leaf removal. Manual removal of half the flowers along the vertical axis of the inflorescence resulted in a shorter Rachis in both cultivars. Conversely, inflorescences treated with gibberellic acid (GA3) and the synthetic cytokinin, 6-benzylaminopurine (BAP) resulted in a longer Rachis while pre-bloom removal of all leaves on the inflorescence-bearing shoot did not alter Rachis length relative to untreated inflorescences. Across the treatments, the cross-sectional areas of the conducting xylem and phloem in the Rachis were positively correlated to Rachis girth, flower number at anthesis, bunch berry number, bunch berry fresh mass and bunch sugar content at harvest. Conversely, average berry size and sugar content were not linked to Rachis vascular area. These data indicate that the morphological and vascular development of the Rachis was more responsive to flower number and plant growth regulators than to leaf removal.
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Flowers regulate the growth and vascular development of the inflorescence Rachis in Vitis vinifera L.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The Rachis, the structural framework of the grapevine (Vitis vinifera L.) inflorescence (and subsequent bunch), consists of a main axis and one or more orders of lateral branches with the flower-bearing pedicels at their fine tips. The Rachis is crucial both for support, and transport from the shoot. Earlier suggestions that the flowers per se affect normal Rachis development are investigated further in this study. Different percentages (0, 25, 50, 75 or 100) of flowers were removed manually one week before anthesis on field-grown vines. Treatment effects on subsequent Rachis development (curvature, vitality, anatomy, starch deposit) were assessed. Sections, both fixed and embedded, and fresh hand-cut were observed by fluorescence and bright-field optics after appropriate staining. Emphasis was on measurement of changes in cross-sectional area of secondary xylem and phloem, and on maturation of fibres and periderm. Specific defects in Rachis development were dependent on the percent and location of flower removal one week prior to anthesis. The Rachises curved inwards where most of the flowers were removed. When fully de-flowered, they became progressively necrotic from the laterals back to the primary axes and from the distal to the proximal end of those axes, with a concurrent disorganisation of their anatomy. A few remaining groups of flowers prevented desiccation and abscission of the Rachis axes proximal to the group, but not distally. Flower removal (50%) reduced Rachis elongation, while 75% removal reduced xylem and phloem area and delayed phloem fibre and periderm development. 75% flower removal did not affect starch present in the Rachis during berry development. Developing flowers affect the growth and vitality of the Rachis and the development of its vascular and support structures. The extent of these effects depends on the cultivar and the number and position of flowers remaining after some are removed one week before anthesis.
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The amino acid distribution in Rachis xylem sap and phloem exudate of Vitis vinifera 'Cabernet Sauvignon' bunches.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Martin J. Canny, Suzy Y. RogiersAbstract:Amino acids are essential to grape berry and seed development and they are transferred to the reproductive structures through the phloem and xylem from various locations within the plant. The diurnal and seasonal dynamics of xylem and phloem amino acid composition in the leaf petiole and bunch Rachis of field-grown Cabernet Sauvignon are described to better understand the critical periods for amino acid import into the berry. Xylem sap was extracted by the centrifugation of excised leaf petioles and Rachises, while phloem exudate was collected by immersing these structures in an ethylenediaminetetraacetic acid (EDTA) buffer. Glutamine and glutamic acid were the predominant amino acids in the xylem sap of both grapevine Rachises and petioles, while arginine and glycine were the principal amino acids of the phloem exudate. The amino acid concentrations within the xylem sap and phloem exudate derived from these structures were greatest during anthesis and fruit set, and a second peak occurred within the Rachis phloem at the onset of ripening. The concentrations of the amino acids within the phloem and xylem sap of the Rachis were highest just prior to or after midnight while the flow of sugar through the Rachis phloem was greatest during the early afternoon. Sugar exudation rates from the Rachis was greater than that of the petiole phloem between anthesis and berry maturity. In summary, amino acid and sugar delivery through the vasculature to grape berries fluctuates over the course of the day as well as through the season and is not necessarily related to levels near the source.
Yuan-ying Peng - One of the best experts on this subject based on the ideXlab platform.
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Genome-wide quantitative trait locus mapping identifies multiple major loci for brittle Rachis and threshability in Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum Shao)
PloS one, 2014Co-Authors: Yunfeng Jiang, Xiu-jin Lan, Wei Luo, Xingchen Kong, Ji-rui Wang, Yu-ming Wei, Qian-tao Jiang, Yaxi Liu, Yuan-ying PengAbstract:Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum Shao) is a semi-wild hexaploid wheat resource that is only naturally distributed in the Qinghai-Tibet Plateau. Brittle Rachis and hard threshing are two important characters of Tibetan semi-wild wheat. A whole-genome linkage map of T. aestivum ssp. tibetanum was constructed using a recombinant inbred line population (Q1028×ZM9023) with 186 lines, 564 diversity array technology markers, and 117 simple sequence repeat markers. Phenotypic data on brittle Rachis and threshability, as two quantitative traits, were evaluated on the basis of the number of average spike Rachis fragments per spike and percent threshability in 2012 and 2013, respectively. Quantitative trait locus (QTL) mapping performed using inclusive composite interval mapping analysis clearly identified four QTLs for brittle Rachis and three QTLs for threshability. However, three loci on 2DS, 2DL, and 5AL showed pleiotropism for brittle Rachis and threshability; they respectively explained 5.3%, 18.6%, and 18.6% of phenotypic variation for brittle Rachis and 17.4%, 13.2%, and 35.2% of phenotypic variation for threshability. A locus on 3DS showed an independent effect on brittle Rachis, which explained 38.7% of the phenotypic variation. The loci on 2DS and 3DS probably represented the effect of Tg and Br1, respectively. The locus on 5AL was in very close proximity to the Q gene, but was different from the predicted q in Tibetan semi-wild wheat. To our knowledge, the locus on 2DL has never been reported in common wheat but was prominent in T. aestivum ssp. tibetanum accession Q1028. It remarkably interacted with the locus on 5AL to affect brittle Rachis. Several major loci for brittle Rachis and threshability were identified in Tibetan semi-wild wheat, improving the understanding of these two characters and suggesting the occurrence of special evolution in Tibetan semi-wild wheat.
Geoffrey R. Scollary - One of the best experts on this subject based on the ideXlab platform.
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Vascular development of the grapevine (Vitis vinifera L.) inflorescence Rachis in response to flower number, plant growth regulators and defoliation.
Journal of plant research, 2017Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The grapevine inflorescence is a determinate panicle and as buds emerge, shoot, flower and Rachis development occur simultaneously. The growth and architecture of the Rachis is determined by genetic and environmental factors but here we examined the role of flower and leaf number as well as hormones on its elongation and vascular development. The consequences of Rachis morphology and vascular area on berry size and composition were also assessed. One week prior to anthesis, Merlot and Cabernet Sauvignon field vines were exposed to manual flower removal, exogenous plant growth regulators or pre-bloom leaf removal. Manual removal of half the flowers along the vertical axis of the inflorescence resulted in a shorter Rachis in both cultivars. Conversely, inflorescences treated with gibberellic acid (GA3) and the synthetic cytokinin, 6-benzylaminopurine (BAP) resulted in a longer Rachis while pre-bloom removal of all leaves on the inflorescence-bearing shoot did not alter Rachis length relative to untreated inflorescences. Across the treatments, the cross-sectional areas of the conducting xylem and phloem in the Rachis were positively correlated to Rachis girth, flower number at anthesis, bunch berry number, bunch berry fresh mass and bunch sugar content at harvest. Conversely, average berry size and sugar content were not linked to Rachis vascular area. These data indicate that the morphological and vascular development of the Rachis was more responsive to flower number and plant growth regulators than to leaf removal.
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Flowers regulate the growth and vascular development of the inflorescence Rachis in Vitis vinifera L.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Suzy Y. RogiersAbstract:The Rachis, the structural framework of the grapevine (Vitis vinifera L.) inflorescence (and subsequent bunch), consists of a main axis and one or more orders of lateral branches with the flower-bearing pedicels at their fine tips. The Rachis is crucial both for support, and transport from the shoot. Earlier suggestions that the flowers per se affect normal Rachis development are investigated further in this study. Different percentages (0, 25, 50, 75 or 100) of flowers were removed manually one week before anthesis on field-grown vines. Treatment effects on subsequent Rachis development (curvature, vitality, anatomy, starch deposit) were assessed. Sections, both fixed and embedded, and fresh hand-cut were observed by fluorescence and bright-field optics after appropriate staining. Emphasis was on measurement of changes in cross-sectional area of secondary xylem and phloem, and on maturation of fibres and periderm. Specific defects in Rachis development were dependent on the percent and location of flower removal one week prior to anthesis. The Rachises curved inwards where most of the flowers were removed. When fully de-flowered, they became progressively necrotic from the laterals back to the primary axes and from the distal to the proximal end of those axes, with a concurrent disorganisation of their anatomy. A few remaining groups of flowers prevented desiccation and abscission of the Rachis axes proximal to the group, but not distally. Flower removal (50%) reduced Rachis elongation, while 75% removal reduced xylem and phloem area and delayed phloem fibre and periderm development. 75% flower removal did not affect starch present in the Rachis during berry development. Developing flowers affect the growth and vitality of the Rachis and the development of its vascular and support structures. The extent of these effects depends on the cultivar and the number and position of flowers remaining after some are removed one week before anthesis.
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The amino acid distribution in Rachis xylem sap and phloem exudate of Vitis vinifera 'Cabernet Sauvignon' bunches.
Plant physiology and biochemistry : PPB, 2016Co-Authors: Aude M. Gourieroux, Bruno Holzapfel, Margaret E. Mccully, Geoffrey R. Scollary, Martin J. Canny, Suzy Y. RogiersAbstract:Amino acids are essential to grape berry and seed development and they are transferred to the reproductive structures through the phloem and xylem from various locations within the plant. The diurnal and seasonal dynamics of xylem and phloem amino acid composition in the leaf petiole and bunch Rachis of field-grown Cabernet Sauvignon are described to better understand the critical periods for amino acid import into the berry. Xylem sap was extracted by the centrifugation of excised leaf petioles and Rachises, while phloem exudate was collected by immersing these structures in an ethylenediaminetetraacetic acid (EDTA) buffer. Glutamine and glutamic acid were the predominant amino acids in the xylem sap of both grapevine Rachises and petioles, while arginine and glycine were the principal amino acids of the phloem exudate. The amino acid concentrations within the xylem sap and phloem exudate derived from these structures were greatest during anthesis and fruit set, and a second peak occurred within the Rachis phloem at the onset of ripening. The concentrations of the amino acids within the phloem and xylem sap of the Rachis were highest just prior to or after midnight while the flow of sugar through the Rachis phloem was greatest during the early afternoon. Sugar exudation rates from the Rachis was greater than that of the petiole phloem between anthesis and berry maturity. In summary, amino acid and sugar delivery through the vasculature to grape berries fluctuates over the course of the day as well as through the season and is not necessarily related to levels near the source.
