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Biomorphological characteristic of breeding samples of representatives of the genus Miscanthus, obtained in vitro Texto completo
2019
Лашук, С. О
Biomorphological characteristic of breeding samples of representatives of the genus Miscanthus, obtained in vitro Texto completo
2019
Лашук, С. О
Purpose. Estimate phenological and morphological characteristics of Miscanthus giganteus J. M. Greef & Deuter ex Hodkinson & Renvoize, M. sacchariflorus (Maxim) Benth. and M. sinensis Anderss., obtained in vitro, and M. giganteus, propagated by rhizomimes (ex vitro) to attract them to the breeding process and create new forms of miscanthus for use in bioenergy. Methods. Seeds of M. sinensis, as well as M. sacchariflorus (2n), M. sacchariflorus (4n), introduced into culture and propagated in vitro according to commonly used methods (M. D. Melnychuk, A. Plazek et al.) were used in the studies. Phenological observations were carried out according to the methods of V. V. Zinchenko, M. V. Roik, D. B. Rakhmetov, and others. Statistical processing of the obtained data was carried out according to M. A. Shelamov and others. Results. M. sacchariflorus (2n) in the conditions of the Forest-Steppe of Ukraine does not enter into the flowering phase, whereas in M. sacchariflorus (4n) the flowering phase begins a month earlier than M. sinensis, which is an obstacle for transpollination of these species in the natural environment. M. giganteus, reproduced by rhizomes, in overwhelming majority of indicators (stem height and diameter, number of interstices and leaves, leaf area, length and width of cluster) dominate all species of mescanthus obtained in vitro. But the number of stems in the bush of M. sinensis is the highest (63 pcs.) and is almost 2–4 times higher than those of M. giganteus, obtained from risomes and in vitro. It has been revealed that the most promising forms for bioenergy use are M. sinensis, whose productivity is about 7 kg/m2 of green mass and M. giganteus, propagated by rhizomimes (ex vitro), where the mass of the aerial part is almost 9 kg/m2. But M. sacchariflorus (2n) and M. sacchariflorus (4n) should not be considered as promising species for use in bioenergy purposes, because their performance is very low compared to other species and is only 0.25 and 2.05 kg above ground mass from 1 m2. Conclusions. On the basis of the obtained data, the most promising forms of Miscanthus were established to attract them into the breeding process and to obtain new varieties with high biomass productivity for the needs of bioenergy.
Mostrar más [+] Menos [-]Biomorphological characteristic of breeding samples of representatives of the genus Miscanthus, obtained in vitro | Біоморфологічна характеристика селекційних зразків представників роду Miscanthus, отриманих в умовах in vitro | Биоморфологическая характеристика селекционных образцов представителей рода Miscanthus, полученых в условиях in vitro Texto completo
2019
Лашук, С. О.
Purpose. Estimate phenological and morphological characteristics of Miscanthus giganteus J. M. Greef & Deuter ex Hodkinson & Renvoize, M. sacchariflorus (Maxim) Benth. and M. sinensis Anderss., obtained in vitro, and M. giganteus, propagated by rhizomimes (ex vitro) to attract them to the breeding process and create new forms of miscanthus for use in bioenergy. Methods. Seeds of M. sinensis, as well as M. sacchariflorus (2n), M. sacchariflorus (4n), introduced into culture and propagated in vitro according to commonly used methods (M. D. Melnychuk, A. Plazek et al.) were used in the studies. Phenological observations were carried out according to the methods of V. V. Zinchenko, M. V. Roik, D. B. Rakhmetov, and others. Statistical processing of the obtained data was carried out according to M. A. Shelamov and others. Results. M. sacchariflorus (2n) in the conditions of the Forest-Steppe of Ukraine does not enter into the flowering phase, whereas in M. sacchariflorus (4n) the flowering phase begins a month earlier than M. sinensis, which is an obstacle for transpollination of these species in the natural environment. M. giganteus, reproduced by rhizomes, in overwhelming majority of indicators (stem height and diameter, number of interstices and leaves, leaf area, length and width of cluster) dominate all species of mescanthus obtained in vitro. But the number of stems in the bush of M. sinensis is the highest (63 pcs.) and is almost 2–4 times higher than those of M. giganteus, obtained from risomes and in vitro. It has been revealed that the most promising forms for bioenergy use are M. sinensis, whose productivity is about 7 kg/m2 of green mass and M. giganteus, propagated by rhizomimes (ex vitro), where the mass of the aerial part is almost 9 kg/m2. But M. sacchariflorus (2n) and M. sacchariflorus (4n) should not be considered as promising species for use in bioenergy purposes, because their performance is very low compared to other species and is only 0.25 and 2.05 kg above ground mass from 1 m2. Conclusions. On the basis of the obtained data, the most promising forms of Miscanthus were established to attract them into the breeding process and to obtain new varieties with high biomass productivity for the needs of bioenergy. | Цель. Оценить фенологические и морфологические характеристики растений мискантуса гигантского (Miscanthus giganteus J.M.Greef & Deuter ex Hodkinson & Renvoize), мискантуса сахароцветного (M. sacchariflorus (Maxim) Benth.) и мискантуса китайского (M. sinensis Anderss.), полученных в культуре in vitro, и мискантуса гигантского, размноженного ризомами (ex vitro) для привлечения их в селекционный процесс и создания новых форм мискантуса для использования в биоэнергетике. Методы. В исследованиях использовали семена M. sinensis, а также M. sacchariflorus (2n), растения M. sacchariflorus (4n), введены в культуру и размножены в условиях in vitro по общепринятым методикам (М. Д. Мельничук и др., A. Plazek et al.). Фенологические наблюдения проводили по методикам В. А. Зинченко, М. В. Роика, Д. Б. Рахметова и др.; статистическую обработку полученных данных – по М. А. Шеламовой и др. Результаты. M. sacchariflorus (2n) в условиях Лесостепи Украины в фазу цветения не вступает, зато у M. sacchariflorus (4n) цветение начинается на месяц раньше, чем у M. sinensis, что является препятствием для переопыления этих видов в естественной среде. M. giganteus, размноженный ризомами, по подавляющиму большинству показателей (высота и диаметр стебля, количество междоузлий и листьев, площадь листьев, длина и ширина метелки) доминирует над всеми видами мискантуса, полученными в культуре in vitro. Однако количество стеблей в кусте у растений M. sinensis является наибольшим (63 шт.) и почти в 2–4 раза превышает показатели растений M. giganteus, полученных из ризом и в in vitro. Наиболее перспективными формами для использования в биоэнергетике является M. sinensis и размноженный ризомами (ex vitro) M. giganteus, урожайность зеленой массы которых составляла примерно 7 и 9 кг/м2 соответственно, тогда как M. sacchariflorus (2n) и M. sacchariflorus (4n) для этого непригодны, ведь формируют лишь 0,25 и 2,05 кг наземной массы с 1 м2. Выводы. На основе полученных данных установлены перспективные формы Miscanthus для привлечения их в селекционный процесс и получения новых сортов с высокой продуктивностью биомассы для нужд биоэнергетики. | Мета. Оцінити фенологічні та морфологічні характеристики рослин міскантусу гігантського (Miscanthus giganteus J.M.Greef & Deuter ex Hodkinson & Renvoize), міскантусу цукроквіткового (M. sacchariflorus (Maxim) Benth.) та міскантусу китайського (M. sinensis Anderss.), отриманих у культурі in vitro, та міскантусу гігантського, розмноженого ризомами (ex vitro) для залучення їх у селекційний процес і створення нових форм міскантусу для використання в біоенергетиці. Методи. У дослідженнях використовували насіння M. sinensis, а також M. sacchariflorus (2n), рослини M. sacchariflorus (4n), уведені в культуру та розмножені в умовах in vitro за загальноприйнятими методиками (М. Д. Мельничук, A. Plazek та ін.). Фенологічні спостереження проводили за методиками В. О. Зінченко, М. В. Роїка, Д. Б. Рахметова та ін.; статистичну обробку отриманих даних – за М. А. Шеламовой та ін. Результати. M. sacchariflorus (2n) в умовах Лісостепу України у фазу цвітіння не вступає, натомість у M. sacchariflorus (4n) цвітіння починається на місяць раніше, ніж у M. sinensis, що є перешкодою для перезапилення цих видів у природньому середовищі. M. giganteus, розмножений ризомами, за переважною більшістю показників (висота та діаметр стебла, кількість міжвузлів та листків, площа листків, довжина та ширина волоті) домінує над усіма видами міскантусу, отриманими в культурі in vitro. Проте кількість стебел у кущі в рослин M. sinensis є найбільшою (63 шт.) і майже у 2–4 рази перевищує показники рослин M. giganteus, отриманих із ризом та в in vitro. Найперспективнішими формами для використання в біоенергетиці є M. sinensis та розмножений ризомами (ex vitro) M. giganteus, урожайність зеленої маси яких становила приблизно 7 і 9 кг/м2 відповідно, тоді як M. sacchariflorus (2n) та M. sacchariflorus (4n) для цього є непридатними, адже формують лише 0,25 та 2,05 кгназемної маси з 1 м2. Висновки. На основі отриманих даних установлено найперспективніші форми Miscanthus для залучення їх у селекційний процес та отримання нових сортів з високою продуктивністю біомаси для потреб біоенергетики.
Mostrar más [+] Menos [-]The genomes of Scedosporium between environmental challenges and opportunism Texto completo
2023
Francesco Venice | Federica Spina | Domenico Davolos | Stefano Ghignone | Giovanna Cristina Varese
Abstract Emerging fungal pathogens are a global challenge for humankind. Many efforts have been made to understand the mechanisms underlying pathogenicity in bacteria, and OMICs techniques are largely responsible for those advancements. By contrast, our limited understanding of opportunism and antifungal resistance is preventing us from identifying, limiting and interpreting the emergence of fungal pathogens. The genus Scedosporium (Microascaceae) includes fungi with high tolerance to environmental pollution, whilst some species can be considered major human pathogens, such as Scedosporium apiospermum and Scedosporium boydii. However, unlike other fungal pathogens, little is known about the genome evolution of these organisms. We sequenced two novel genomes of Scedosporium aurantiacum and Scedosporium minutisporum isolated from extreme, strongly anthropized environments. We compared all the available Scedosporium and Microascaceae genomes, that we systematically annotated and characterized ex novo in most cases. The genomes in this family were integrated in a Phylum-level comparison to infer the presence of putative, shared genomic traits in filamentous ascomycetes with pathogenic potential. The analysis included the genomes of 100 environmental and clinical fungi, revealing poor evolutionary convergence of putative pathogenicity traits. By contrast, several features in Microascaceae and Scedosporium were detected that might have a dual role in responding to environmental challenges and allowing colonization of the human body, including chitin, melanin and other cell wall related genes, proteases, glutaredoxins and magnesium transporters. We found these gene families to be impacted by expansions, orthologous transposon insertions, and point mutations. With RNA-seq, we demonstrated that most of these anciently impacted genomic features responded to the stress imposed by an antifungal compound (voriconazole) in the two environmental strains S. aurantiacum MUT6114 and S. minutisporum MUT6113. Therefore, the present genomics and transcriptomics investigation stands on the edge between stress resistance and pathogenic potential, to elucidate whether fungi were pre-adapted to infect humans. We highlight the strengths and limitations of genomics applied to opportunistic human pathogens, the multifactoriality of pathogenicity and resistance to drugs, and suggest a scenario where pressures other than anthropic contributed to forge filamentous human pathogens.
Mostrar más [+] Menos [-]Biomorphological characteristic of breeding samples of representatives of the genus Miscanthus, obtained in vitro Texto completo
2019
С. О. Лашук
Biomorphological characteristic of breeding samples of representatives of the genus Miscanthus, obtained in vitro Texto completo
2019
С. О. Лашук
Purpose. Estimate phenological and morphological characteristics of Miscanthus giganteus J. M. Greef & Deuter ex Hodkinson & Renvoize, M. sacchariflorus (Maxim) Benth. and M. sinensis Anderss., obtained in vitro, and M. giganteus, propagated by rhizomimes (ex vitro) to attract them to the breeding process and create new forms of miscanthus for use in bioenergy. Methods. Seeds of M. sinensis, as well as M. sacchariflorus (2n), M. sacchariflorus (4n), introduced into culture and propagated in vitro according to commonly used methods (M. D. Melnychuk, A. Plazek et al.) were used in the studies. Phenological observations were carried out according to the methods of V. V. Zinchenko, M. V. Roik, D. B. Rakhmetov, and others. Statistical processing of the obtained data was carried out according to M. A. Shelamov and others. Results. M. sacchariflorus (2n) in the conditions of the Forest-Steppe of Ukraine does not enter into the flowering phase, whereas in M. sacchariflorus (4n) the flowering phase begins a month earlier than M. sinensis, which is an obstacle for transpollination of these species in the natural environment. M. giganteus, reproduced by rhizomes, in overwhelming majority of indicators (stem height and diameter, number of interstices and leaves, leaf area, length and width of cluster) dominate all species of mescanthus obtained in vitro. But the number of stems in the bush of M. sinensis is the highest (63 pcs.) and is almost 2–4 times higher than those of M. giganteus, obtained from risomes and in vitro. It has been revealed that the most promising forms for bioenergy use are M. sinensis, whose productivity is about 7 kg/m2 of green mass and M. giganteus, propagated by rhizomimes (ex vitro), where the mass of the aerial part is almost 9 kg/m2. But M. sacchariflorus (2n) and M. sacchariflorus (4n) should not be considered as promising species for use in bioenergy purposes, because their performance is very low compared to other species and is only 0.25 and 2.05 kg above ground mass from 1 m2. Conclusions. On the basis of the obtained data, the most promising forms of Miscanthus were established to attract them into the breeding process and to obtain new varieties with high biomass productivity for the needs of bioenergy.
Mostrar más [+] Menos [-]Post-genomic approaches to understanding interactions between fungi and their environment Texto completo
2011
De Vries,Ronald | Benoit,Isabelle | Doehlemann,Gunther | Kobayashi,Tetsuo | Magnuson,Jon | Panisko,Ellen | Baker,Scott | Lebrun,Marc-Henri
Fungi inhabit every natural and anthropogenic environment on Earth. They have highly varied life-styles including saprobes (using only dead biomass as a nutrient source), pathogens (feeding on living biomass), and symbionts (co-existing with other organisms). These distinctions are not absolute as many species employ several life styles (e.g. saprobe and opportunistic pathogen, saprobe and mycorrhiza). To efficiently survive in these different and often changing environments, fungi need to be able to modify their physiology and in some cases will even modify their local environment. Understanding the interaction between fungi and their environments has been a topic of study for many decades. However, recently these studies have reached a new dimension. The availability of fungal genomes and development of postgenomic technologies for fungi, such as transcriptomics, proteomics and metabolomics, have enabled more detailed studies into this topic resulting in new insights. Based on a Special Interest Group session held during IMC9, this paper provides examples of the recent advances in using (post-)genomic approaches to better understand fungal interactions with their environments.
Mostrar más [+] Menos [-]Obtaining plant Miscanthus sacchariflorus (Maxim.) Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis Texto completo
2017
Гонтаренко, С. М | Лашук, С. О
Obtaining plant Miscanthus sacchariflorus (Maxim.) Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis Texto completo
2017
Гонтаренко, С. М | Лашук, С. О
Purpose. To obtain Miscanthus sacchariflorus (Maxim.) Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis. Methods. Biotechnological procedures, mathematical and statistical analyses. Results. Composition of nutrient medium was developed intended for induction of callusogenesis from Miscanthus seeds with a poor germination and viability of seedlings – Murashige and Skoog (MS) medium was modified for the amount of macroelements (half-dose) that was supplemented with amino acids (300 mg/l of glutamic acid, 50 mg/l of aspartic acid, 5 mg/l of tyrosine, 3 mg/l of arginine, 2 mg/l of hydroxyproline) and plant growth regulators [2,5 mg/l of 2.4D (2.4-Dichlorophenoxyacetic acid), 0,6 mg/l of BAP (6-Benzyl-aminopurine) and 0,3 mg/l of ABA (Abscisic acid)]. Composition of nutrient medium was developed for regeneration of microplants from callus – agar MS medium was modified for the amount of macroelements (half-dose) supplemented with vitamins: 10 mg/l of thiaminum, 1,0 mg/l of pyridoxine, 1,0 mg/l of nicotinic acid (by White), 1,0 mg/l of ascorbic acid, 250 mg/l of glutamic acid, 2,0 mg/l of BAP, 0,3 mg/l of NAA (Naphthaleneacetic acid). On this medium, 100% regeneration of M. sacchariflorus (Maxim.) Hack and 50% regeneration of M. sinensis Andersson was obtained. Due to media modification aimed at initiating callusogenesis and microplants regeneration, reproduction factor of M. sinensis was increased 20 times at the average, M. sacchariflorus – 35–40 times. Conclusions. Plants of M. sacchariflorus (Maxim.) Hack and M. sinensis Andersson were obtained in vitro culture by initiation of callusogenes and microplants regeneration from the Miscanthus seeds with poor germination and viability on nutrient media of certain composition.
Mostrar más [+] Menos [-]Obtaining plant Miscanthus sacchariflorus (Maxim.) Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis Texto completo
2017
С. М. Гонтаренко | С. О. Лашук
Purpose. To obtain Miscanthus sacchariflorus (Maxim.) Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis. Methods. Biotechnological procedures, mathematical and statistical analyses. Results. Composition of nutrient medium was developed intended for induction of callusogenesis from Miscanthus seeds with a poor germination and viability of seedlings – Murashige and Skoog (MS) medium was modified for the amount of macroelements (half-dose) that was supplemented with amino acids (300 mg/l of glutamic acid, 50 mg/l of aspartic acid, 5 mg/l of tyrosine, 3 mg/l of arginine, 2 mg/l of hydroxyproline) and plant growth regulators [2,5 mg/l of 2.4D (2.4-Dichlorophenoxyacetic acid), 0,6 mg/l of BAP (6-Benzyl-aminopurine) and 0,3 mg/l of ABA (Abscisic acid)]. Composition of nutrient medium was developed for regeneration of microplants from callus – agar MS medium was modified for the amount of macroelements (half-dose) supplemented with vitamins: 10 mg/l of thiaminum, 1,0 mg/l of pyridoxine, 1,0 mg/l of nicotinic acid (by White), 1,0 mg/l of ascorbic acid, 250 mg/l of glutamic acid, 2,0 mg/l of BAP, 0,3 mg/l of NAA (Naphthaleneacetic acid). On this medium, 100% regeneration of M. sacchariflorus (Maxim.) Hack and 50% regeneration of M. sinensis Andersson was obtained. Due to media modification aimed at initiating callusogenesis and microplants regeneration, reproduction factor of M. sinensis was increased 20 times at the average, M. sacchariflorus – 35–40 times. Conclusions. Plants of M. sacchariflorus (Maxim.) Hack and M. sinensis Andersson were obtained in vitro culture by initiation of callusogenes and microplants regeneration from the Miscanthus seeds with poor germination and viability on nutrient media of certain composition.
Mostrar más [+] Menos [-]Оцінка селекційного матеріалу за морфо-цитологічними особливостями генеративних органів рослин роду Miscanthus | Evaluation of breeding material on the basis of morphological and cytological characteristics of the reproductive organs of plants of the genus Miscanthus Texto completo
2023
S. O. Lashuk
Оцінка селекційного матеріалу за морфо-цитологічними особливостями генеративних органів рослин роду Miscanthus | Evaluation of breeding material on the basis of morphological and cytological characteristics of the reproductive organs of plants of the genus Miscanthus Texto completo
2023
S. O. Lashuk
Мета. Вивчити морфологічні й цитологічні особливості пиляків, пилку та маточок рослин роду Miscanthus, отриманих в умовах in vitro. Методи. Препарати маточок, незапліднених насіннєвих зачатків, пиляків та пилку, незабарвлені або забарвлені розчином карміну (2%) в оцтовій кислоті (45%) чи розчином метиленового синього, досліджували методом світлової мікроскопії. Вимірювання для рослин різних видів міскантусу, а також підрахунок кількості пилку різного діаметра здійснювали в десятиразовому повторенні. Результати. Вивчено морфологічні й цитологічні особливості генеративних органів китайського, цукроквіткового та гігантського видів міскантусу. Встановлено, що квітка цієї рослини однодомна, містить як тичинки, так і маточку. Забарвлення пиляків жовте або рожево-жовте, їхні тканини складаються з видовжених клітин довжиною 70–100 мкм. Маточка має зав’язь з двома стовпчиками, що несуть довгі (2,0–2,8 мм) перисті приймочки, колір яких варіюється від білого до яскраво-рожевого. Форма пір’ячок маточки помірно розгалужена; довжина – 160–300 мкм; ширина – 20–30 мкм; розташування почергове; кількість маленьких відгалужень становить 10–15 шт. Пилок різних видів міскантусу відрізняється за якісними та кількісними ознаками, зокрема у M. sinensis і M. sacchariflorus він характеризується округлою формою, вирівняністю та однорідністю (43–48 мкм у діаметрі), а в M. giganteus є більш гетерогенним за розміром (діаметр 23–45 мкм). Пилок має одну округлу орнаментовану пору діаметром 2,7–4,0 мкм. Висновки. За результатами проведених досліджень надано морфологічну та цитологічну характеристику генеративних органів рослин M. sinensis, M. sacchariflorus, M. giganteus, а саме: маточок, пиляків і пилку. Дані, що отримано, слід враховувати в подальшій селекційній роботі у процесі створення ди- та триплоїдних гібридів міскантусу. | Purpose. To study in vitro the morphological and cytological characteristics of anthers, pollen and pistils of plants of the genus Miscanthus. Methods. Preparations of pistils, unpollinated seed buds, anthers and pollen, unstained or stained with a solution of carmine (2%) in acetic acid (45%) or methylene blue solution, were examined by light microscopy. Measurements for plants of different Miscanthus species, as well as counting the number of pollen of different diameters, were made in ten replicates. Results. The morphological and cytological characteristics of the reproductive organs of M. sinensis, M. sacchariflorus and M. giganteus species were studied. It was found that the flower of this plant is monoecious, containing both stamens and a pistil. The color of the anthers is yellow or pinkish-yellow, their tissues consist of elongated cells 70–100 µm long. The pistil has a two-column ovary with long (2.0–2.8 mm) pinnate stigmas which vary in color from white to bright pink. The shape of the pistil feather is moderately branched; length – 160–300 µm; width – 20–30 µm; alternate position; the number of small branches is 10–15 pcs. The pollen of different Miscanthus species differ in qualitative and quantitative characteristics, in particular in M. sinensis and M. sacchariflorus it is characterized by a rounded shape, evenness and uniformity (43–48 µm in diameter), whereas in M. giganteus it is more heterogeneous in size (23–45 µm in diameter). The pollen has a rounded, decorated pore with a diameter of 2.7–4.0 µm. Conclusions. According to the results of the conducted research, the morphological and cytological characteristics of the reproductive organs of M. sinensis, M. sacchariflorus and M. giganteus, namely: pistils, anthers and pollen, were provided. The data obtained should be taken into account in future breeding for the production of di- and triploid Miscanthus hybrids.
Mostrar más [+] Menos [-]The extremely halotolerant black yeast Hortaea werneckii - a model for intraspecific hybridization in clonal fungi Texto completo
2019
Polona Zalar | Jerneja Zupančič | Cene Gostinčar | Janja Zajc | G. Sybren de Hoog | Filomena De Leo | Armando Azua-Bustos | Nina Gunde-Cimerman
Abstract The polymorphic black yeast Hortaea werneckii (Capnodiales, Ascomycota) is extremely halotolerant (growth from 0 to 30% [w/v] NaCl) and has been extensively studied as a model for halotolerance in Eukaryotes for over two decades. Its most frequent sources are hypersaline environments and adjacent sea-water habitats in temperate, subtropical and tropical climates. Although typically saprobic, H. werneckii can also act as a commensal coloniser on human skin, causing tinea nigra on hands and soles. Here, we report that addition of NaCl to culture media expands the growth range of H. werneckii to 37 °C, which explains its colonisation of human skin, with its increased salinity. The morphological and physiological plasticity/ versatility of H. werneckii indicate that a species complex might be involved. This was investigated in this polyphasic taxonomic analysis based on the global diversity of H. werneckii strains collected from hypersaline environments, and from humans and animals. Analysis of D1/D2domains of 28S and internal transcribed spacer rDNA revealed 10 and 17 genotypes, respectively, that were not always compliant. The genotypes have global distributions. Human and environmental strains with the same genotypes are intermingled. Due to the limited number of phylogenetically informative characters in the ribosomal DNA dataset, the partial genes encoding for β-tubulin (BTB) and mini-chromosome maintenance protein (MCM7) were also sequenced. The use of these genes was hampered by ambiguous sequences obtained by Sanger sequencing, as a consequence of the diploid and highly heterozygous genome of many H. werneckii strains. Analysis of the BTB and MCM7 genes showed that in some cases two copies of the gene from the same genome are positioned in distant phylogenetic clusters of the intraspecific gene tree. Analysis of whole-genome sequences of selected H. werneckii strains generally confirmed the phylogenetic distances estimated on the basis of ribosomal genes, but also showed substantial reticulation within the phylogenetic history of the strains. This is in line with the hypothesis that the diploid genomes of H. werneckii were formed by hybridizations, which have sometimes occurred between relatively divergent strains.
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