The evolution of reproductive structures in seed plants: a re-examination based on insights from developmental genetics

In a minute proportion of angiosperm species, rehydrating foliage can revive from airdryness or even from equilibration with air of ~0% RH. Such desiccation tolerance is known from vegetative cells of some species of algae and of major groups close to the evolutionary path of the angiosperms. It is also found in the reproductive structures of some algae, moss spores and probably the aerial spores of other terrestrial cryptogamic taxa. The occurrence of desiccation tolerance in the seed plants is overwhelmingly in the aerial reproductive structures; the pollen and seed embryos. Spatially and temporally, pollen and embryos are close ontogenetic derivatives of the angiosperm microspores and megaspores respectively. This suggests that the desiccation tolerance of pollen and embryos derives from the desiccation tolerance of the spores of antecedent taxa and that the basic pollen/embryo mechanism of desiccation tolerance has eventually become expressed also in the vegetative tissue of certain angiosperm species whose drought avoidance is inadequate in micro-habitats that suffer extremely xeric episodes. The protective compounds and processes that contribute to desiccation tolerance in angiosperms are found in the modern groups related to the evolutionary path leading to the angiosperms and are also present in the algae and in the cyanobacteria. The mechanism of desiccation tolerance in the angiosperms thus appears to have its origins in algal ancestors and possibly in the endosymbiotic cyanobacteria-related progenitor of chloroplasts and the bacteria-related progenitor of mitochondria. The mechanism may involve the regulation and timing of the accumulation of protective compounds and of other contributing substances and processes.

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Upper Carboniferous seed fern (Pteridospermophyta) pollen organs from Silesia (Poland) and related evolution considerations

Monographiae Botanicae ◽

10.5586/mb.2010.001 ◽

2014 ◽

Vol 100 ◽

pp. 1-81 ◽

Cited By ~ 3

Author(s):

Grzegorz Pacyna ◽

Danuta Zdebska

Keyword(s):

New Species ◽

New Genus ◽

Radial Symmetry ◽

Seed Plants ◽

New Genus And Species ◽

Typical Species ◽

Reproductive Structures ◽

The North ◽

Compound Pollen ◽

First Time

Extinct seed ferns (Pteridospermophyta) fill a key position in the evolutionary tree of seed plants. Their reproductive structures enable to recognition of the interrelationship within seed ferns and other seed plants descending from them. Seed fern reproductive structures from Poland are very rarely found and very poorly known, especially the pollen organs to which this paper is dedicated. A new genus and species Silesiatheca formosa Pacyna & Zdebska, gen. et sp. nov. of lyginopteridalean aggregated synangia was recognized based on specimens preserved within sideritic nodules from Sosnowiec. The genus Codonotheca is recognized from European Carboniferous for the first time. The least evolutionarily advanced species of Codonotheca − Codonotheca silesiaca Pacyna & Zdebska sp. nov., is described based on specimens with weakly expressed radial symmetry and slight fusion of the sporangia. this species matches the hitherto hypothetical simplest species of Codonotheca very well, constituting the initial form for all the more compound pollen organs of Medullosales. For the first time in the European Carboniferous the North American species Aulacotheca campbellii (White, 1900) Halle, 1933 is recognized. A new emended diagnosis for the typical species Boulayatheca fertilis (Kidston, 1914) Taylor & Kurmann, 1985 is proposed, based on specimens from Poland. Two new species of genus Boulayatheca Taylor & Kurmann, 1985 are recognized. Boulayatheca ciliata Pacyna & Zdebska, sp. nov. with a synangium surface covered with hairs (a feature hitherto unknown in the Boulayatheca genus) and Boulayatheca saganii Pacyna & Zdebska, sp. nov. with a markedly elongated synangium. Occurrence of Whittleseya Newberry, 1853a emend. Halle, 1933 typical species − Whittleseya elegans Newberry, 1853a was confirmed in Lower Silesia based on new specimens. Some specimens referred to earlier in the literature as W. elegans were ascribed here to the new species W. silesiaca Pacyna & Zdebska, sp. nov., which differs from typical species in synangium shape and sporangia clustering into groups. The new species Whittleseya campanulata Pacyna & Zdebska, sp. nov. has a large synangium and sporangia clustering into groups. Heterogeneity within the genus Whittleseya is recognized, where some species, including those new described here, probably formed compound synangia. The aggregated synangia of Medullosales are recognized in thecompression state of preservation for the first time they are the base for establishing a new genus and species Kotasotheca annaeadamii Pacyna & Zdebska, gen. et sp. nov. The genus Dolerotheca Halle, 1933 was recognized in the Polish Carboniferous for the first time and a new species Dolerotheca migierii Pacyna & Zdebska, sp. nov. was described. T.N. Taylor’s model of evolution of medullosalean pollen organs was confirmed, and the new taxa described were included within it.

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Colourful cones: how did flower colour first evolve?

Journal of Experimental Botany ◽

10.1093/jxb/erz479 ◽

2019 ◽

Vol 71 (3) ◽

pp. 759-767 ◽

Cited By ~ 3

Author(s):

Paula J Rudall

Keyword(s):

Colour Vision ◽

Flower Colour ◽

Flowering Plants ◽

Seed Plants ◽

Plant Tissues ◽

Secondary Effect ◽

Reproductive Structures ◽

Seed Cone ◽

Evolutionary Pathways ◽

Flower Pigments

Abstract Angiosperms that are biotically pollinated typically produce flowers with bright and contrasting colours that help to attract pollinators and hence contribute to the reproductive success of the species. This colourful array contrasts with the much less multicoloured reproductive structures of the four living gymnosperm lineages, which are mostly wind pollinated, though cycads and Gnetales are predominantly pollinated by insects that feed on surface fluids from the pollination drops. This review examines the possible evolutionary pathways and cryptic clues for flower colour in both living and fossil seed plants. It investigates how the ancestral flowering plants could have overcome the inevitable trade-off that exists between attracting pollinators and minimizing herbivory, and explores the possible evolutionary and biological inferences from the colours that occur in some living gymnosperms. The red colours present in the seed-cone bracts of some living conifers result from accumulation of anthocyanin pigments; their likely primary function is to help protect the growing plant tissues under particular environmental conditions. Thus, the visual cue provided by colour in flower petals could have first evolved as a secondary effect, probably post-dating the evolution of bee colour vision but occurring before the subsequent functional accumulation of a range of different flower pigments.

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An interactive key (Lucid) for the identifying of the genera of seed plants from the Ducke Reserve, Manaus, AM, Brazil

Rodriguésia ◽

10.1590/s2175-78602012000100005 ◽

2012 ◽

Vol 63 (1) ◽

pp. 055-064 ◽

Cited By ~ 3

Author(s):

Volker Bittrich ◽

Clara Sampaio D. Souza ◽

Rubens L.G. Coelho ◽

Milena V. Martins ◽

Michael J.G. Hopkins ◽

...

Keyword(s):

Seed Plants ◽

Seed Plant ◽

Electronic Publication ◽

Field Guide ◽

Reproductive Structures ◽

The Poor ◽

On Line ◽

Vegetative Characters ◽

Amazonian Brazil ◽

Reproductive Characters

The identification of Amazonian plants is still difficult for many reasons, one being the lack of collections over large areas of the region. As a consequence of the poor knowledge on the Amazonian flora, many taxonomic publications (revisions and floristic treatments) become out of date within a few years. In this context, the on-line publication of taxonomic treatises has been suggested, since it allows constant data updates; and this type of publication should therefore be more valued by the scientific community. An excellent field guide for the Ducke Reserve (Manaus, central Amazonian Brazil) was published, based exclusively on vegetative characters. However, the presence of reproductive structures in the collected material does not facilitate identification with this type of field guide. Furthermore, as in any printed key, the text cannot be updated, except through a new edition. As an example of a way to facilitate the identification of Amazonian plants, an interactive, multiple-entry key to the seed plant genera that occur in the Ducke Reserve was created using the program Lucid 3.5. The key includes vegetative and reproductive characters and many illustrations, and is available on-line. We discuss here the peculiarities and advantages of this type of electronic publication.

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Caracterización preliminar de una secuencia homóloga del gen LEAFY en gimnospermas (Pinus radiata Lemm.)

Botanical Sciences ◽

10.17129/botsci.1501 ◽

2017 ◽

pp. 7

Author(s):

Liz Y. Izquierdo ◽

Rosalinda Tapia ◽

Francisco Vergara ◽

Elena Álvarez-Buylla

Keyword(s):

Dna Sequences ◽

Genomic Dna ◽

Higher Plants ◽

Structural Complexity ◽

Homologous Sequence ◽

Seed Plants ◽

Seed Plant ◽

Inflorescence Development ◽

Reproductive Structures ◽

Molecular Components

A fragment from an homologous sequence of LEAFY (LFY) gene that encodes for a transcription factor involved in early events during inflorescence development was cloned from genomic DNA of P. radiata, a non flowering seed plant. Using PCR technic we amplified an 85 bp fragment flanked by two primers designed from some DNA sequences obtained from different species of angiosperms. The fragment obtained was.highly similar to A. thaliana gene LFY between 5077 and 5143 bases and hybridized with a LFY clone from this species. This result suggests that sorne molecular components of the functional and structural complexity of the development of reproductive structures in higher plants are an ancestral property of seed plants and not a novelty in the angiosperm lineage.

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Freeze substitution fixation of fungal reproductive structures and spores

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156936 ◽

1989 ◽

Vol 47 ◽

pp. 990-991

Author(s):

C. W. Mims ◽

E. A. Richardson

Keyword(s):

Plant Pathogens ◽

Freeze Substitution ◽

Uranyl Acetate ◽

Chemical Fixation ◽

Dialysis Membrane ◽

Razor Blade ◽

Thin Sections ◽

Reproductive Structures ◽

Dry Down ◽

Diamond Knife

The advantages of freeze substitution fixation over conventional chemical fixation for preservation of ultrastructural details in fungi have been discussed by various authors. As most ascomycetes, basidiomycetes and deuteromycetes do not fix well using conventional chemical fixation protocols, freeze substitution has attracted the attention of many individuals interested in fungal ultrastructure. Thus far most workers using this technique on fungi have concentrated on thin walled somatic hyphae. However, in our laboratory we have experimented with the use of freeze substitution on a variety of fungal reproductive structures and spores with promising results.Here we present data on freeze substituted samples of sporangia of the zygomycete Umbellopsis vinacea, basidia of Exobasidium camelliae var. gracilis, developing teliospores of the smut Sporisorium sorghi, germinating teliospores of the rust Gymnosporangium clavipes, germinating conidia of the deuteromycete Cercosporidium personatum, and developing ascospores of Ascodesmis nigricans.Spores of G. clavipes and C. personatum were deposited on moist pieces of sterile dialysis membrane where they hydrated and germinated. Asci of A. nigricans developed on pieces of dialysis membrane lying on nutrient agar plates. U. vinacea was cultured on small pieces of agar-coated wire. In the plant pathogens E. camelliae var. gracilis and S. sorghi, a razor blade was used to remove smal1 pieces of infected host issue. All samples were plunged directly into liquid propane and processed for study according to Hoch.l Samples on dialysis membrane were flat embedded. Serial thin sections were cut using a diamond knife, collected on slot grids, and allowed to dry down onto Formvar coated aluminum racks. Sections were post stained with uranyl acetate and lead citrate.

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Developmental Genetics of the Flower

10.1016/s0065-2296(06)x4400-2 ◽

2006 ◽

Keyword(s):

Developmental Genetics

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ПоражениесеменныхрастенийредисагрибомAlbugocandidaприпервичномсеменоводствевМосковскойобласти

Kartofel` i ovoshi ◽

10.25630/pav.2019.49.69.008 ◽

2019 ◽

Author(s):

A.N. Khovrin ◽

D.A. Yanaeva

Keyword(s):

Seed Production ◽

Seed Plants ◽

Albugo Candida ◽

Generative Phase

В статье описаны симптомы поражения семенных растений редиса A. candida, дана оценка ряда сортов с разной устойчивостью к A. candida. Описаны способы борьбы с этим заболеванием при элитном семеноводстве редиса. В результате двулетней оценки образцов питомника размножения выявлено, что есть сортовая специфика устойчивости к Albugo candida. Более склонен к поражению в генеративную фазу развития сорт Кармен, наиболее устойчив к патогену сорт Меркадо.The symptoms of A. candida on seed plants radish are described a number of varieties with different resistance to A. candida are evaluated. The methods of combating of this disease in elite seed production of radish are described. As a result of twoyear evaluation of breeding nursery samples it was revealed that there is varietal specificity of resistance to A. candida. The Carmen cultivar is more prone to disease in the generative phase, the most resistant to the pathogen is Mercado cultivar.

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Итоги селекционно-семеноводческой работы с редечными культурами на Дальнем Востоке

Kartofel` i ovoshi ◽

10.25630/pav.2018.2.17589 ◽

2018 ◽

Author(s):

V  Leunov ◽

Y  Mikheev

Keyword(s):

Far East ◽

Seed Plants ◽

Vegetable Crops ◽

Soil Pathogens ◽

Climate Conditions ◽

State Register ◽

Golden Horn ◽

The Far East ◽

High Yielding Varieties ◽

Technological Methods

Расширение ассортимента потребляемых овощных культур – одна из основных задач в селекционно-семеноводческой работе с редечными культурами на Дальнем Востоке. В статье приводятся данные о селекции редечных культур (лобы, дайкона, редьки и др.) на Приморской овощной опытной станции. В результате проведения многолетних исследований и реализации ряда научных программ был создан новый исходный материал для селекции. В настоящем материале также подведены итоги актуальных направлений в селекции редечных культур в условиях муссонного климата. Селекционно-семеноводческие исследования в условиях климата Дальнего Востока с использованием индивидуального, а также индивидуально-семейственного методов отбора, разработка и внедрение технологических приемов первичного и сортового семеноводства обеспечили создание перспективного селекционного материала. Выделены ценные генисточники для создания новых сортообразцов китайского, японского и европейского подвидов редьки с высокими иммунологическими, продуктивными и товарными качествами, повышенными биохимическими показателями, высокой устойчивостью к переувлажнению почвы и возбудителями болезней. Созданы и включены в Госреестр РФ высокопродуктивные сорта китайского подвида редьки (лоба) Малиновый шар и Золотой рог, европейского подвида зимней редьки Ночная красавица, устойчивые к переувлажнению почвы и цветушности, бактериальным заболеваниям. В результате более чем двадцатилетних исследований изучены морфологические и биологические особенности формирования семенных растений редьки, использование эффективных элементов отбора в сочетании с агротехническими приемами возделывания. Усовершенствованы технологические методы первичного и товарного семеноводства редьки, выделены благоприятные агроклиматические зоны выращивания семенных растений, способствующие получению высококачественных семян при сохранении ими высоких биологических и хозяйственных признаков. Для условий муссонного климата Дальнего Востока внедрена в производство система первичного и сортового семеноводства редьки с использованием пересадочной и беспересадочной технологии выращивания. Результаты работы открывают дорогу к созданию новых высокоурожайных российских сортов и гибридов редечных культур.Expansion of the range of consumption of vegetable crops is one of the main tasks in the breeding and seed work with regions cultures in the Far East. The article presents data on the breeding radishes cultures (loba, daikon, radish, etc.) on the Maritime vegetable experiment station. As a result of years of research and implementation of a number of research programs has created a new source material for breeding. In this paper also summarize the current trends in the selection of radishes cultures in conditions of monsoonal climate. Breeding and seed research in the climate conditions of the Far East with the use of individual and individual and family methods of selection, development and implementation of technological methods of primary and varietal seed production ensured the development of advanced breeding material. Allocated valuable genitocracy to create new varieties of Chinese, Japanese and European subspecies of radishes cultures with high immunological, productive and commercial qualities, elevated biochemical parameters, high resistance to waterlogging and soil pathogens. Created and included in the state register of the Russian Federation high-yielding varieties of Chinese subspecies of radish (loba) a Crimson ball and the Golden horn, the European subspecies winter radish Night beauty, resistant to waterlogging of the soil and bolting and bacterial diseases. As a result of more than twenty years studied the morphological and biological peculiarities of formation of seed plants of radishes, the use of effective elements of selection in combination with agrotechnical methods of cultivation. Improved technological methods of primary and commercial seed radishes allocated to favorable agro-climatic zones of cultivation of seed plants, which would produce high-quality seeds while preserving their high biological and economic characteristics. For the conditions of monsoon climate of the Far East implemented in the production system of primary and varietal seed radishes using transit and non-stop growing technologies. The results of this work open the way to the creation of new high-yielding Russian varieties and hybrids of radishes cultures.

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Оригинальное семеноводство овощных корнеплодных культур в Московской области

Kartofel` i ovoshi ◽

10.25630/pav.2018.2.17588 ◽

2018 ◽

Author(s):

A  Khovrin ◽

M  Ibragimbekov ◽

R  Bagrov

Keyword(s):

Species Composition ◽

Seed Production ◽

Moscow Region ◽

Seed Plants ◽

Pests And Diseases ◽

Root Crops ◽

Seed Growing ◽

In Cells

Даны результаты оригинального первичного семеноводства корнеплодных культур в изоляторах в селекционно-семеноводческом центре агрохолдинга «Поиск» (Раменский район Московской области). Описаны технологические особенности процесса семеноводства, представлен видовой состав болезней и вредителей семенных растений в условиях исследований.The results of the original primary seed growing of root crops in cells at breeding and seed production centre of Poisk Agro Holding (Ramensky district, Moscow region) are given. Technological peculiarities of the process of seed production, species composition of pests and diseases of seed plants in terms of research are presented.

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