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Patricia I Leonardi - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales
Phycologia, 2012Co-Authors: Amelia A Vouilloud, Patricia I Leonardi, Eduardo J. CáceresAbstract:Vouilloud A.A., Leonardi P.I. and Caceres E.J. 2012. Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales. Phycologia 51: 239–246. DOI: 10.2216/10-102.1 Spermatogenesis in Chara contraria var. nitelloides was studied in depth. The following features were analysed: the development of cytosol, nucleus, plastids, vacuoles and dictyosomes, the coiling of the cell body, and the alignment of the organelles with the multimicrotubular roots. All of them were correlated with the dynamics of the absolute configuration of the flagellar apparatus, i.e. basal bodies and flagella. This integrating study in C. contraria var. nitelloides gives a complete portrayal of the process of spermatogenesis for the first time in the order Charales by recognizing the synchronies between the overall stages of spermatogenesis and all the developmental stages of the flagellar apparatus.
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ultrastructure of mature male gametes of nitella hyalina Charales charophyta
Phycologia, 2010Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:Abstract Vouilloud A.A., Caceres E.J. and Leonardi P.I. 2010. Ultrastructure of mature male gametes of Nitella hyalina (Charales, Charophyta). Phycologia 49: 508–511. DOI: 10.2216/09-111.1 This article describes the ultrastructure of male gametes of Nitella hyalina. Microtubular roots did not surround mitochondria completely. The number of microtubules varied from 12 to19 at the level of mitochondria, from 24 to 31 at the level of the nucleus and from 10 to 21 at different levels of the plastids. The three-membered root is clearly discernible only up to the level of mitochondria. At the rearmost level of the gamete, microtubules were separated in bunches of two to six microtubules each. Mature gametes of N. hyalina were compared with those of other species of Chara and Nitella. This comparative analysis suggests that certain male gamete ultrastructure traits are regularly dissimilar at genus level.
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changes in the absolute configuration of the basal flagellar apparatus and evidence of centrin during male gametogenesis in chara contraria var nitelloides Charales charophyta
Plant Systematics and Evolution, 2005Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:The absolute configurations of the basal/flagellar apparatus during male gametogenesis of Chara contraria var. nitelloides (Charales, Charophyta) were carefully analysed. Emphasis was placed on the changes in the angles and lengths of the basal bodies, the microtubular root angles and the development of the distal as well the proximal connecting fibers. Six principal stages were recognized: a) parallel, non-axonemal, developing basal bodies connected by a non-striated, proximal fiber; b) non-parallel, non-axonemal, mature basal bodies connected by a developing, striated, distal fiber; c) non-parallel, axonemal basal bodies connected by a fully developed, striated, distal fiber; d) opposite, axonemal basal bodies not connected by fibers, e) axonemal basal bodies not connected by fibers and directed backwards and f) parallel, axonemal basal bodies not connected by fibers. A headpiece, a 3-membered root and a reduced multilayered structure developed during ontogeny. The initial parallel disposition of the basal bodies, the initial lack of MLS and the presence of only two microtubular roots from the very inception of the basal apparatus development, suggest a Mamiella-like ancestor for Charales. Ontogenetic evidence supports previous ideas in the sense that similarities of sperm morphology of charalean and bryophytan gametes are likely due to convergent evolution. In addition, the present study clearly reveals the presence of centrin in Charales.
Борисова Е.В. - One of the best experts on this subject based on the ideXlab platform.
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Видовое разнообразие и экология Charales (Charophyta) зоны широколиственных лесов Украины
'National Academy of Sciences of Ukraine (Co. LTD Ukrinformnauka)', 2017Co-Authors: Борисова Е.В.Abstract:Исследовано видовое разнообразие харальных водорослей зоны широколиственных лесов Украины. Выявлено 60 местонахождений 11 видов родов Charales: Chara L. (7), Nitella C. Agardh (3), Tolypella (A. Braun) A. Braun (1), в т. ч. несколько местонахождений редких для флоры Украины видов: Chara aspera Dethard. ex Willd., Ch. intermedia A. Braun, Ch. tenuispina A. Braun и Tolypella intricata (Trentep. ex Roth) Leonh. Установлено доминирование космополитов, широко распространенных в Украине, Ch. globularis Thuill. (23,3%) и Ch. vulgaris L. (38,3%). Анализ оригинальных и литературных данных, касающихся экологии Charales зоны широколиственных лесов, свидетельствует о том, что относительная ограниченность их видового состава связана в основном с отсутствием на исследуемой территории крупных озер или озерных групп, наиболее благоприятных для развития данной группы бентосных растений, и сильным антропогенным воздействием. Сравнение видового состава Charales зоны широколиственных лесов и сопредельных территорий Польского, Волынского, Житомирского Полесья, Украинских Карпат и Правобережной Лесостепи указывает на его переходной характер, что также связано с сильной антропогенной трансформацией данной территории в процессе ее длительного земледельческого освоения.A study of the Charales (Charophyta) species diversity of the zone of deciduous forests in the Ukraine (ZDF) has revealed 60 new localities for 11 species from the genera Chara L. (7), Nitella C. Agardh (3), and Tolypella (A. Braun) A. Braun (1). Among them, the noteworthy records are Chara aspera Dethard. ex Willd., Ch. intermedia A. Braun, Ch. tenuispina A. Braun, rarely occurring in the studied area, and Tolypella intricata (Trentep. ex Roth) Leonh., a new species for the flora of Ukraine. The most frequently occurring species were cosmopolitans Ch. globularis Thuill. (23.3%) and Ch. vulgaris L. (38.3%). An analysis of the original and literature data on the ecology of Charales species found in the ZDF shows that the relative scarcity of their composition is mainly due to the absence of large lakes or lake groups in the area, and a strong anthropogenic impact. A comparison of the species composition of Charales of the ZDF with those of adjacent territories: the Polish, Volyn, Zhytomir Polissia, Ukrainian Carpathians and the Right-bank Forest-Steppe indicates its transitional character. This is probably due to a strong anthropogenic transformation of the territory during continuous agricultural reclamation
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Анализ флоры Charales (Charophyta) Украины
'National Academy of Sciences of Ukraine (Co. LTD Ukrinformnauka)', 2016Co-Authors: Борисова Е.В.Abstract:Проведен систематический, экологический и географический анализ флоры харальных водорослей Украины на основе оригинальных и литературных данных.The flora of Charales of Ukraine was analyzed in terms of taxonomic structure, ecological peculiarities, and geographical distribution
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Особенности распространения Charales в Украинском Полесье
Інститут ботаніки ім. М.Г. Холодного НАН України, 2014Co-Authors: Борисова Е.В.Abstract:Приведены обобщенные данные о видовом составе Charales Украинского Полесья и его областей. Выявлены закономерности их распространения на данной территории в зависимости от типа водоема, степени минерализации и рН воды
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Харовые водоросли (Charales) Житомирского Полесья (Украина)
Інститут ботаніки ім. М.Г. Холодного НАН України, 2009Co-Authors: Борисова Е.В., Орлов А.А.Abstract:Приведены результаты изучения видового состава харовых водорослей (Charales) Жито-мирского Полесья. Обнаружено девять видов, относящихся к родам Chara L. (5) и Nitella C. Agardh (4). Показано, что на исследованной территории наиболее часто встречаются редкие виды Ch. delicatula C. Agardh, N. flexilis (L.) C. Agardh, N. mucronata (A. Braun) Miq. in H.C. Hall, занесенные в Красный список Charales Украины, и значительно реже Ch. contraria A. Braun ex Kütz., Ch. fragilis Desv. in Loisel., Ch. vulgaris L., широко распространенные в Украине. Впервые для Житомирского Полесья приводятся Ch. aspera Dethard. ex Willd. и N. gracilis (Sm.) C. Agardh. Подтверждена для данной территории (после 1972 г.) находка N. capillaris (Krock.) J. Groves et Bull.-Webst. Проведено сравнение видового состава Charales Житомирского Полесья с таковым Волынского и Киевского. Отмечены особенности их распространения в водоемах всего Правобережного Украинского Полесья.The results of a study on species composition of the Zytomir Polissia charophytes (Charales) are presented. Nine taxa belonging to the genera Chara L. (5) and Nitella C. Agardh (4) were found. It was shown that Ch. delicatula C. Agardh, N. flexilis (L.) C. Agardh, and N. mucronata (A. Braun) Miq. in H.C. Hall, rare species in the Red Check List of Charales of the Ukraine, occur most frequently within the investigated territory whereas Ch. contraria A. Braun ex Kütz., Ch. fragilis Desv. in Loisel., and Ch. vulgaris L., widespread species, are less frequent in these investigated territories. Ch. aspera Dethard. ex Willd. and N. gracilis (Sm.) C. Agardh are first cited for Zytomir Polissia. A record of N. capillaris (Krock.) J. Groves et Bull.-Webst. is confirmed for this territory (after 1972). The species composition of Charales of Zytomir Polissia was compared to those of Volyn and Kiev Polissia. Species distribution of Charales in water bodies throughout the Right-Bank Ukrainian Polissia has been revealed
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Материалы к флоре Charales юго-запада Украины
Інститут ботаніки ім. М.Г. Холодного НАН України, 2008Co-Authors: Борисова Е.В., Ткаченко Ф.П.Abstract:Приведен систематический список Charales юго-запада Украины, составленный на основании оригинальных и литературных данных, с указанием местонахождения, распространения в Украине и общего распространения. Он включает 16 видов, относящихся к родам Chara L. (13), Lamprothamnium J. Groves (1), Nitella C. Agardh (1) и Nitellopsis Hy (1). Из них в настоящее время на исследуемой территории обнаружено 10 видов, в т. ч. три новых (Chara connivens Salzm. ex A. Braun, Ch. uzbekistanica Hollerb., Nitella mucronata (A. Braun) Miq. in H.C. Hall). Ранее указанные Ch. braunii C.C. Gmelin, Ch. contraria A. Braun ex Kűtz., Ch. fragilis Desv. in Loisel., Ch. horrida Wahlst., Ch. tenuispina A. Braun и Ch. schaffneri (A. Braun) Allen нами не были обнаружены. Значительно сократились площади произрастания Ch. aculeolata Kűtz. in Rchb., Lamprothamnium papulosum (Wallr.) J. Groves, Nitellopsis obtusa (Desv. in Loisel.) J. Groves, а также Ch. canescens Desv. et Loisel. in Loisel, занесенного в Красную книгу Украины (1996). Выявленные изменения во флоре Charales юго-запада Украины, по-видимому, связаны с влиянием антропогенного фактора и общим повышением минерализации континентальных водоемов данной территории.A taxonomic list of Charales of the southwest Ukraine (comprising original and literature data) with synonyms, distribution in Ukraine and general distribution is given. It contains 16 species belonging to Chara L. (13), Lamprothamnium J. Groves (1), Nitella C. Agardh (1), and Nitellopsis Hy (1). Recently ten species have been found in the investigated territory including three new ones (Ch. connivens Salzm. ex A. Braun, Ch. uzbekistanica Hollerb., N. mucronata (A. Braun) Miq. in H.C. Hall). However, Ch. braunii C.C. Gmelin, Ch. contraria A. Braun ex Kűtz., Ch. fragilis Desv. in Loisel., Ch. horrida Wahlst., Ch. tenuispina A. Braun, and Ch. schaffneri (A. Braun) Allen known from the previous references have not been revealed. The growth areas of Ch. aculeolata Kűtz. in Rchb., L. papulosum (Wallr.) J. Groves, Nitellopsis obtusa (Desv. in Loisel.) J. Groves and Ch. canescens Desv. et Loisel. in Loisel. (Red Book of Ukraine species) have strongly reduced. Maybe these changes in the flora of Charales of the southwest Ukraine connect with anthropogenic impact and general increasing of salinity in inland water bodies of the investigated territory
I. V. Blinova - One of the best experts on this subject based on the ideXlab platform.
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Виды рода Nitella (Streptophyta: Charales) в Мурманской области Species of Nitella (Streptophyta: Charales) from Murmansk Oblast (Russia)
2015Co-Authors: R. E. Romanov, I. V. BlinovaAbstract:1 Центральный сибирский ботанический сад СО РАН, ул. Золотодолинская, 101, Новосибирск, 630090, Россия; Новосибирский государственный университет, ул. Пирогова, 2, Новосибирск, 630090, Россия 1 Central Siberian Botanical Garden, Siberian Branch of Russian Academy of Sciences, Zolotodolinakaya str., 101, Novosibirsk, 630090, Russia; Novosibirsk State University, Pirogov Str., 2, Novosibirsk, 630090, Russia. E-mail: romanov_r_e@ngs.ru
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виды рода nitella streptophyta Charales в мурманской области
Turczaninowia, 2015Co-Authors: R. E. Romanov, I. V. BlinovaAbstract:Seven new records of Nitella are published from Murmansk Oblast (Russia) following recent revision of specimens deposited in KPABG and IBIW. The new records relate to N. flexilis (L.) C. Agardh, N. opaca (Bruz.) C. Agardh, or Nitella sp. ster. (flexilis vel opaca), and they are the first records for the south and south-east part of the region. A list of all records of Nitella species has been compiled together with a map. These species of Nitella do not seem to be rare in Murmansk Region, and the sparsity of their recorded distribution probably reflects insufficient local study of this group. New records of Nitella and other Charales are expected in the future, and these may provide significant insights into the ecology of charophytes in higher latitudes.
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Species of Nitella (Streptophyta: Charales) from Murmansk Oblast (Russia)
Altay State University, 2015Co-Authors: R. E. Romanov, I. V. BlinovaAbstract:Seven new records of Nitella are published from Murmansk Oblast (Russia) following recent revision of specimens deposited in KPABG and IBIW. The new records relate to N. flexilis (L.) C. Agardh, N. opaca (Bruz.) C. Agardh, or Nitella sp. ster. (flexilis vel opaca), and they are the first records for the south and south-east part of the region. A list of all records of Nitella species has been compiled together with a map. These species of Nitella do not seem to be rare in Murmansk Region, and the sparsity of their recorded distribution probably reflects insufficient local study of this group. New records of Nitella and other Charales are expected in the future, and these may provide significant insights into the ecology of charophytes in higher latitudes.
Amelia A Vouilloud - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales
Phycologia, 2012Co-Authors: Amelia A Vouilloud, Patricia I Leonardi, Eduardo J. CáceresAbstract:Vouilloud A.A., Leonardi P.I. and Caceres E.J. 2012. Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales. Phycologia 51: 239–246. DOI: 10.2216/10-102.1 Spermatogenesis in Chara contraria var. nitelloides was studied in depth. The following features were analysed: the development of cytosol, nucleus, plastids, vacuoles and dictyosomes, the coiling of the cell body, and the alignment of the organelles with the multimicrotubular roots. All of them were correlated with the dynamics of the absolute configuration of the flagellar apparatus, i.e. basal bodies and flagella. This integrating study in C. contraria var. nitelloides gives a complete portrayal of the process of spermatogenesis for the first time in the order Charales by recognizing the synchronies between the overall stages of spermatogenesis and all the developmental stages of the flagellar apparatus.
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ultrastructure of mature male gametes of nitella hyalina Charales charophyta
Phycologia, 2010Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:Abstract Vouilloud A.A., Caceres E.J. and Leonardi P.I. 2010. Ultrastructure of mature male gametes of Nitella hyalina (Charales, Charophyta). Phycologia 49: 508–511. DOI: 10.2216/09-111.1 This article describes the ultrastructure of male gametes of Nitella hyalina. Microtubular roots did not surround mitochondria completely. The number of microtubules varied from 12 to19 at the level of mitochondria, from 24 to 31 at the level of the nucleus and from 10 to 21 at different levels of the plastids. The three-membered root is clearly discernible only up to the level of mitochondria. At the rearmost level of the gamete, microtubules were separated in bunches of two to six microtubules each. Mature gametes of N. hyalina were compared with those of other species of Chara and Nitella. This comparative analysis suggests that certain male gamete ultrastructure traits are regularly dissimilar at genus level.
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Changes in the absolute configuration of the basal/flagellar apparatus and evidence of centrin during male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta)
Plant Systematics and Evolution, 2005Co-Authors: Amelia A Vouilloud, E. J. Cáceres, P. I. LeonardiAbstract:The absolute configurations of the basal/flagellar apparatus during male gametogenesis of Chara contraria var. nitelloides (Charales, Charophyta) were carefully analysed. Emphasis was placed on the changes in the angles and lengths of the basal bodies, the microtubular root angles and the development of the distal as well the proximal connecting fibers. Six principal stages were recognized: a) parallel, non-axonemal, developing basal bodies connected by a non-striated, proximal fiber ; b) non-parallel, non-axonemal, mature basal bodies connected by a developing, striated, distal fiber; c) non-parallel, axonemal basal bodies connected by a fully developed, striated, distal fiber; d) opposite, axonemal basal bodies not connected by fibers, e) axonemal basal bodies not connected by fibers and directed backwards and f) parallel, axonemal basal bodies not connected by fibers . A headpiece, a 3-membered root and a reduced multilayered structure developed during ontogeny. The initial parallel disposition of the basal bodies, the initial lack of MLS and the presence of only two microtubular roots from the very inception of the basal apparatus development, suggest a Mamiella -like ancestor for Charales. Ontogenetic evidence supports previous ideas in the sense that similarities of sperm morphology of charalean and bryophytan gametes are likely due to convergent evolution. In addition, the present study clearly reveals the presence of centrin in Charales.
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changes in the absolute configuration of the basal flagellar apparatus and evidence of centrin during male gametogenesis in chara contraria var nitelloides Charales charophyta
Plant Systematics and Evolution, 2005Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:The absolute configurations of the basal/flagellar apparatus during male gametogenesis of Chara contraria var. nitelloides (Charales, Charophyta) were carefully analysed. Emphasis was placed on the changes in the angles and lengths of the basal bodies, the microtubular root angles and the development of the distal as well the proximal connecting fibers. Six principal stages were recognized: a) parallel, non-axonemal, developing basal bodies connected by a non-striated, proximal fiber; b) non-parallel, non-axonemal, mature basal bodies connected by a developing, striated, distal fiber; c) non-parallel, axonemal basal bodies connected by a fully developed, striated, distal fiber; d) opposite, axonemal basal bodies not connected by fibers, e) axonemal basal bodies not connected by fibers and directed backwards and f) parallel, axonemal basal bodies not connected by fibers. A headpiece, a 3-membered root and a reduced multilayered structure developed during ontogeny. The initial parallel disposition of the basal bodies, the initial lack of MLS and the presence of only two microtubular roots from the very inception of the basal apparatus development, suggest a Mamiella-like ancestor for Charales. Ontogenetic evidence supports previous ideas in the sense that similarities of sperm morphology of charalean and bryophytan gametes are likely due to convergent evolution. In addition, the present study clearly reveals the presence of centrin in Charales.
Eduardo J. Cáceres - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales
Phycologia, 2012Co-Authors: Amelia A Vouilloud, Patricia I Leonardi, Eduardo J. CáceresAbstract:Vouilloud A.A., Leonardi P.I. and Caceres E.J. 2012. Ultrastructure of male gametogenesis in Chara contraria var. nitelloides (Charales, Charophyta) revisited: a model for a better characterization of the process in Charales. Phycologia 51: 239–246. DOI: 10.2216/10-102.1 Spermatogenesis in Chara contraria var. nitelloides was studied in depth. The following features were analysed: the development of cytosol, nucleus, plastids, vacuoles and dictyosomes, the coiling of the cell body, and the alignment of the organelles with the multimicrotubular roots. All of them were correlated with the dynamics of the absolute configuration of the flagellar apparatus, i.e. basal bodies and flagella. This integrating study in C. contraria var. nitelloides gives a complete portrayal of the process of spermatogenesis for the first time in the order Charales by recognizing the synchronies between the overall stages of spermatogenesis and all the developmental stages of the flagellar apparatus.
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ultrastructure of mature male gametes of nitella hyalina Charales charophyta
Phycologia, 2010Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:Abstract Vouilloud A.A., Caceres E.J. and Leonardi P.I. 2010. Ultrastructure of mature male gametes of Nitella hyalina (Charales, Charophyta). Phycologia 49: 508–511. DOI: 10.2216/09-111.1 This article describes the ultrastructure of male gametes of Nitella hyalina. Microtubular roots did not surround mitochondria completely. The number of microtubules varied from 12 to19 at the level of mitochondria, from 24 to 31 at the level of the nucleus and from 10 to 21 at different levels of the plastids. The three-membered root is clearly discernible only up to the level of mitochondria. At the rearmost level of the gamete, microtubules were separated in bunches of two to six microtubules each. Mature gametes of N. hyalina were compared with those of other species of Chara and Nitella. This comparative analysis suggests that certain male gamete ultrastructure traits are regularly dissimilar at genus level.
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changes in the absolute configuration of the basal flagellar apparatus and evidence of centrin during male gametogenesis in chara contraria var nitelloides Charales charophyta
Plant Systematics and Evolution, 2005Co-Authors: Amelia A Vouilloud, Eduardo J. Cáceres, Patricia I LeonardiAbstract:The absolute configurations of the basal/flagellar apparatus during male gametogenesis of Chara contraria var. nitelloides (Charales, Charophyta) were carefully analysed. Emphasis was placed on the changes in the angles and lengths of the basal bodies, the microtubular root angles and the development of the distal as well the proximal connecting fibers. Six principal stages were recognized: a) parallel, non-axonemal, developing basal bodies connected by a non-striated, proximal fiber; b) non-parallel, non-axonemal, mature basal bodies connected by a developing, striated, distal fiber; c) non-parallel, axonemal basal bodies connected by a fully developed, striated, distal fiber; d) opposite, axonemal basal bodies not connected by fibers, e) axonemal basal bodies not connected by fibers and directed backwards and f) parallel, axonemal basal bodies not connected by fibers. A headpiece, a 3-membered root and a reduced multilayered structure developed during ontogeny. The initial parallel disposition of the basal bodies, the initial lack of MLS and the presence of only two microtubular roots from the very inception of the basal apparatus development, suggest a Mamiella-like ancestor for Charales. Ontogenetic evidence supports previous ideas in the sense that similarities of sperm morphology of charalean and bryophytan gametes are likely due to convergent evolution. In addition, the present study clearly reveals the presence of centrin in Charales.