The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Peter Kitin - One of the best experts on this subject based on the ideXlab platform.
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Origin, morphology, and anatomy of Fasciation in plants cultured in vivo and in vitro
Plant Growth Regulation, 2011Co-Authors: Ivan Iliev, Peter KitinAbstract:Fasciation (or cristation) is a variation in the morphology of plants, characterized by the development of various widened and flattened organs. According to origin, Fasciations are classified as physiological or genetic but comparatively little is known on their epigenetic or genetic nature at the molecular level. Physiological Fasciations are caused by natural environmental factors or artificial treatments including exogenously applied growth regulators. CLAVATA genes ( CLV1 , CLV2 , and CLV3 ) have been shown to be the main genetic factors associated with Fasciation. Despite the great variety of Fasciation-induction factors, Fasciations have similar features of development during the first few weeks, i.e., increased mitotic activity and size of the apical meristem and an altered arrangement of cells in the meristematic zones, often leading to an increased number of organs and changes in the plastochron. The enhanced activity of apical meristem and cambium results in a significantly increased circumference of the stem and enlarged proportions of pith and cortical parenchyma, associated with a delayed differentiation of the vascular tissues. An elliptical or irregular shape of the cross section of a fasciated organ corresponds to a similar shape of the vascular cylinder. Later stages of the ontogenic development of Fasciations are species-specific, may depend on the origin of Fasciation, and in some cases may lead to deviations from the normal structure of the epidermis, shape of leaves, as well as altered development of axillary buds. Studying the causes and patterns of development of Fasciations could provide a better understanding of the growth processes in the vegetative apex. Further anatomical and physiological research should focus on the structure and activity of meristems of fasciated shoots, as well as on their transcriptome analysis, in order to better understand the pattern of Fasciation development.
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Comparative Study of the Variability of Betula Pendula Roth Cultivars During the Propagation in Vitro
Annals of the University of Craiova - Agriculture Montanology Cadastre Series, 2009Co-Authors: Ivan Iliev, Peter Kitin, A. Scaltsoyiannes, Maria Tsaktsira, Mihaela Corneanu, Christos NellasAbstract:Fasciated shoots formation was induced from leaf callus of ‘Fastigiata’, ‘Dalecarlica’, Youngii’, ‘Purpurea’, var. Typica, and var. Melanocortea. Fasciated shoots were not observed to ‘Dalecarlica’. This phenomenon was not observed on all media (S, WPM, and MS) enriched with BAP and highest percentage (from 0.4 +/- 0.1% to 2.0 +/- 0.1%) was obtained on all media containing 10 mg l-1 zeatin. The appearance of fascinated shoots depended from the genotype, type of cytokinin and its concentration. The anatomical study showed that there was no disorder in the tissue position in fascinated shoots. The tissues had the same structural peculiarities as in normal shoots. This distinguishes the Fasciations from pathogenous phenomena. The study showed that the theory for the accretion of adjacent stems as a reason for Fasciation could not be accepted. The most striking difference between normal and fascinated stems was in the shape and size of the vascular cylinder. In addition, the differentiation of xylem of fascinated stems was delayed compared to that of normal stem. This delay of differentiation could be a result from intense mitotic activity of procambium and cambium in fascinated stems.
Yuhong Tang - One of the best experts on this subject based on the ideXlab platform.
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Molecular mapping of the Fasciation mutation in soybean, Glycine max (Leguminosae)
American journal of botany, 2002Co-Authors: H. Caglar Karakaya, Yuhong Tang, Perry B. Cregan, Halina T. KnapAbstract:The spontaneous Fasciation mutation generates novel developmental diversity in cultivated soybean, Glycine max (L.) Merrill. An increased apical dominance in the mutant inhibits axillary buds, causes a branchless phenotype, and restricts reproduction to shoot apices. The Fasciation mutation is encoded by a recessive (f) allele at a single locus. The mutation, despite its importance in soybean development, has no locus assignment on previously reported molecular maps of soybean. A population of 70 F(2) progeny was derived from a cross between 'Clark 63' and the Fasciation mutant. More than 700 molecular markers (amplified restriction fragment length polymorphisms [AFLPs], random amplified polymorphic DNAs [RAPDs], restriction fragment length polymorphisms [RFLPs], and simple sequence repeats [SSRs]) were used in mapping of the Fasciation phenotype. Twenty linkage groups (LGs) corresponding to the public soybean molecular map are represented on the Clark 63 × Fasciation mutant molecular map that spans 3050 centimorgans (cM). The f locus was mapped on LG D1b+W and linked with two AFLPs and four SSR markers (Satt005, Satt141, Satt600, and Satt703). No linkage was found between the f locus and several cDNA polymorphic loci between the wild type and the mutant. The known map position of the f locus and demonstration of the mutant phenotype from early postembryonic throughout reproductive stages provide an excellent resource for investigations of molecular mechanisms affecting soybean ontogeny.
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Expression of Fasciation mutation in apical meristems of soybean, Glycine max (Leguminosae).
American journal of botany, 1997Co-Authors: Yuhong Tang, H.t. SkorupskaAbstract:The phenotype of the apical meristem was used to examine the effect of Fasciation mutation at the f locus in different genetic backgrounds in soybean Glycine max (L.) Merr. Comparisons of meristem development in Fasciation mutant and wild type were conducted with scanning electron microscope (SEM) on isogenic lines BARC-11-11-ff and BARC-11-11-FF at postgermination and early vegetative stages. Studies of apical meristems of three independently originated Fasciation mutants, PI 83945-4, PI 243541, and T173, were carried out at vegetative and early floral transition stages. Corolla Fasciation, the extreme mutant phenotype, was used for comparison of meristem development. Enlargement of the apical meristem and shortened plastochron were observed in the mutant lines 2 d after germination. Similar to Corolla Fasciation, in PI 83945-4, PI 243541, and T173, enlargement of the apical meristem was followed by growth along one axis at the V3 stage and establishment of a ridge-like meristem at the V4 stage. Influence of pedigree on the expression of the Fasciation phenotype was demonstrated by different growth patterns (subangular vs. ridge-like) of the apical meristem in BARC-11-11-ff and PI 243541 with the same f gene. During transition of the apical meristem from vegetative to reproductive stage in all mutant lines further production of leaf primordia ceased. The developmental pattern of the apical meristems suggests that the f locus may have the same allele in Fasciation mutants of independent origin in soybean.
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expression of Fasciation mutation in apical
1997Co-Authors: Yuhong Tang, H.t. SkorupskaAbstract:The phenotype of the apical meristem was used to examine the effect of Fasciation mutation at the f locus in different genetic backgrounds in soybean Glycine max (L.) Merr. Comparisons of meristem development in Fasciation mutant and wild type were conducted with scanning electron microscope (SEM) on isogenic lines BARC- 1I-I1-if and BARC-l 1-1FF at postgermination and early vegetative stages. Studies of apical meristems of three independently originated Fasciation mutants, PI 83945-4, PI 243541, and T173, were carried out at vegetative and early floral transition stages. Corolla Fasciation, the extreme mutant phenotype, was used for comparison of meristem development. Enlargement of the apical meristem and shortened plastochron were observed in the mutant lines 2 d after germination. Similar to Corolla Fasciation, in PI 83945-4, PI 243541, and T173, enlargement of the apical meristem was followed by growth along one axis at the V3 stage and establishment of a ridge-like meristem at the V4 stage. Influence of pedigree on the expression of the Fasciation phenotype was demonstrated by different growth patterns (subangular vs. ridge-like) of the apical meristem in BARC- 11- 1-ff and PI 243541 with the same f gene. During transition of the apical meristem from vegetative to reproductive stage in all mutant lines further production of leaf primordia ceased. The developmental pattern of the apical meristems suggests that the f locus may have the same allele in Fasciation mutants of independent origin in soybean.
Halina T. Knap - One of the best experts on this subject based on the ideXlab platform.
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Molecular mapping of the Fasciation mutation in soybean, Glycine max (Leguminosae)
American journal of botany, 2002Co-Authors: H. Caglar Karakaya, Yuhong Tang, Perry B. Cregan, Halina T. KnapAbstract:The spontaneous Fasciation mutation generates novel developmental diversity in cultivated soybean, Glycine max (L.) Merrill. An increased apical dominance in the mutant inhibits axillary buds, causes a branchless phenotype, and restricts reproduction to shoot apices. The Fasciation mutation is encoded by a recessive (f) allele at a single locus. The mutation, despite its importance in soybean development, has no locus assignment on previously reported molecular maps of soybean. A population of 70 F(2) progeny was derived from a cross between 'Clark 63' and the Fasciation mutant. More than 700 molecular markers (amplified restriction fragment length polymorphisms [AFLPs], random amplified polymorphic DNAs [RAPDs], restriction fragment length polymorphisms [RFLPs], and simple sequence repeats [SSRs]) were used in mapping of the Fasciation phenotype. Twenty linkage groups (LGs) corresponding to the public soybean molecular map are represented on the Clark 63 × Fasciation mutant molecular map that spans 3050 centimorgans (cM). The f locus was mapped on LG D1b+W and linked with two AFLPs and four SSR markers (Satt005, Satt141, Satt600, and Satt703). No linkage was found between the f locus and several cDNA polymorphic loci between the wild type and the mutant. The known map position of the f locus and demonstration of the mutant phenotype from early postembryonic throughout reproductive stages provide an excellent resource for investigations of molecular mechanisms affecting soybean ontogeny.
H.t. Skorupska - One of the best experts on this subject based on the ideXlab platform.
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Expression of Fasciation mutation in apical meristems of soybean, Glycine max (Leguminosae).
American journal of botany, 1997Co-Authors: Yuhong Tang, H.t. SkorupskaAbstract:The phenotype of the apical meristem was used to examine the effect of Fasciation mutation at the f locus in different genetic backgrounds in soybean Glycine max (L.) Merr. Comparisons of meristem development in Fasciation mutant and wild type were conducted with scanning electron microscope (SEM) on isogenic lines BARC-11-11-ff and BARC-11-11-FF at postgermination and early vegetative stages. Studies of apical meristems of three independently originated Fasciation mutants, PI 83945-4, PI 243541, and T173, were carried out at vegetative and early floral transition stages. Corolla Fasciation, the extreme mutant phenotype, was used for comparison of meristem development. Enlargement of the apical meristem and shortened plastochron were observed in the mutant lines 2 d after germination. Similar to Corolla Fasciation, in PI 83945-4, PI 243541, and T173, enlargement of the apical meristem was followed by growth along one axis at the V3 stage and establishment of a ridge-like meristem at the V4 stage. Influence of pedigree on the expression of the Fasciation phenotype was demonstrated by different growth patterns (subangular vs. ridge-like) of the apical meristem in BARC-11-11-ff and PI 243541 with the same f gene. During transition of the apical meristem from vegetative to reproductive stage in all mutant lines further production of leaf primordia ceased. The developmental pattern of the apical meristems suggests that the f locus may have the same allele in Fasciation mutants of independent origin in soybean.
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expression of Fasciation mutation in apical
1997Co-Authors: Yuhong Tang, H.t. SkorupskaAbstract:The phenotype of the apical meristem was used to examine the effect of Fasciation mutation at the f locus in different genetic backgrounds in soybean Glycine max (L.) Merr. Comparisons of meristem development in Fasciation mutant and wild type were conducted with scanning electron microscope (SEM) on isogenic lines BARC- 1I-I1-if and BARC-l 1-1FF at postgermination and early vegetative stages. Studies of apical meristems of three independently originated Fasciation mutants, PI 83945-4, PI 243541, and T173, were carried out at vegetative and early floral transition stages. Corolla Fasciation, the extreme mutant phenotype, was used for comparison of meristem development. Enlargement of the apical meristem and shortened plastochron were observed in the mutant lines 2 d after germination. Similar to Corolla Fasciation, in PI 83945-4, PI 243541, and T173, enlargement of the apical meristem was followed by growth along one axis at the V3 stage and establishment of a ridge-like meristem at the V4 stage. Influence of pedigree on the expression of the Fasciation phenotype was demonstrated by different growth patterns (subangular vs. ridge-like) of the apical meristem in BARC- 11- 1-ff and PI 243541 with the same f gene. During transition of the apical meristem from vegetative to reproductive stage in all mutant lines further production of leaf primordia ceased. The developmental pattern of the apical meristems suggests that the f locus may have the same allele in Fasciation mutants of independent origin in soybean.
Ivan Iliev - One of the best experts on this subject based on the ideXlab platform.
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Origin, morphology, and anatomy of Fasciation in plants cultured in vivo and in vitro
Plant Growth Regulation, 2011Co-Authors: Ivan Iliev, Peter KitinAbstract:Fasciation (or cristation) is a variation in the morphology of plants, characterized by the development of various widened and flattened organs. According to origin, Fasciations are classified as physiological or genetic but comparatively little is known on their epigenetic or genetic nature at the molecular level. Physiological Fasciations are caused by natural environmental factors or artificial treatments including exogenously applied growth regulators. CLAVATA genes ( CLV1 , CLV2 , and CLV3 ) have been shown to be the main genetic factors associated with Fasciation. Despite the great variety of Fasciation-induction factors, Fasciations have similar features of development during the first few weeks, i.e., increased mitotic activity and size of the apical meristem and an altered arrangement of cells in the meristematic zones, often leading to an increased number of organs and changes in the plastochron. The enhanced activity of apical meristem and cambium results in a significantly increased circumference of the stem and enlarged proportions of pith and cortical parenchyma, associated with a delayed differentiation of the vascular tissues. An elliptical or irregular shape of the cross section of a fasciated organ corresponds to a similar shape of the vascular cylinder. Later stages of the ontogenic development of Fasciations are species-specific, may depend on the origin of Fasciation, and in some cases may lead to deviations from the normal structure of the epidermis, shape of leaves, as well as altered development of axillary buds. Studying the causes and patterns of development of Fasciations could provide a better understanding of the growth processes in the vegetative apex. Further anatomical and physiological research should focus on the structure and activity of meristems of fasciated shoots, as well as on their transcriptome analysis, in order to better understand the pattern of Fasciation development.
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Comparative Study of the Variability of Betula Pendula Roth Cultivars During the Propagation in Vitro
Annals of the University of Craiova - Agriculture Montanology Cadastre Series, 2009Co-Authors: Ivan Iliev, Peter Kitin, A. Scaltsoyiannes, Maria Tsaktsira, Mihaela Corneanu, Christos NellasAbstract:Fasciated shoots formation was induced from leaf callus of ‘Fastigiata’, ‘Dalecarlica’, Youngii’, ‘Purpurea’, var. Typica, and var. Melanocortea. Fasciated shoots were not observed to ‘Dalecarlica’. This phenomenon was not observed on all media (S, WPM, and MS) enriched with BAP and highest percentage (from 0.4 +/- 0.1% to 2.0 +/- 0.1%) was obtained on all media containing 10 mg l-1 zeatin. The appearance of fascinated shoots depended from the genotype, type of cytokinin and its concentration. The anatomical study showed that there was no disorder in the tissue position in fascinated shoots. The tissues had the same structural peculiarities as in normal shoots. This distinguishes the Fasciations from pathogenous phenomena. The study showed that the theory for the accretion of adjacent stems as a reason for Fasciation could not be accepted. The most striking difference between normal and fascinated stems was in the shape and size of the vascular cylinder. In addition, the differentiation of xylem of fascinated stems was delayed compared to that of normal stem. This delay of differentiation could be a result from intense mitotic activity of procambium and cambium in fascinated stems.
