Journal articles on the topic 'Endosperma e perisperma'
To see the other types of publications on this topic, follow the link: Endosperma e perisperma.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 24 journal articles for your research on the topic 'Endosperma e perisperma.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
West, M. Marcia, Derrick T. Flannigan, and John N. A. Lott. "Elemental composition of globoids in the perisperm tissue of various seeds." Canadian Journal of Botany 73, no. 6 (June 1, 1995): 954–57. http://dx.doi.org/10.1139/b95-104.
Full textAbstract:
The mature seeds of some angiosperms contain perisperm tissue derived from remains of the nucellus tissue of the ovule. In our transmission electron microscopy studies, the perisperm tissues of the seeds of Yucca brevifolia, Coffea arabica, Beta vulgaris, Piper nigrum, and Zostera capricorni contained naturally electron-dense globoids. Energy dispersive X-ray analysis of globoids from the perisperm tissues of these seeds revealed varying levels of phosphorus, potassium, magnesium, and calcium, results that are consistent with the presence of the mineral nutrient store called phytate. Phosphorus, potassium, magnesium, calcium, and other mineral nutrients, likely stored as phytate, have routinely been located in globoids of endosperm, female gametophyte, and embryo tissues of seeds. Key words: perisperm, globoids, mineral nutrient reserves, phosphorus, seeds, energy dispersive X-ray analysis.
2
De Castro, Renato D., and Pierre Marraccini. "Cytology, biochemistry and molecular changes during coffee fruit development." Brazilian Journal of Plant Physiology 18, no. 1 (March 2006): 175–99. http://dx.doi.org/10.1590/s1677-04202006000100013.
Full textAbstract:
In commercial coffee species (Coffea arabica and Coffea canephora), fruit development is a lengthy process, characterized by tissue changes and evolutions. For example, soon after fecundation and up to mid development, the fruit is mainly constituted of the pericarp and perisperm tissue. Thereafter, the perisperm gradually disappears and is progressively replaced by the endosperm (true seed). Initially present in a "liquid" state, the endosperm hardens as it ripens during the maturation phase, as a result of accumulation of storage proteins, sucrose and complex polysaccharides representing the main reserves of the seed. The last step of maturation is characterized by the dehydration of the endosperm and the color change of the pericarp. Important quantitative and qualitative changes accompany fruit growth, highlighting the importance of its study to better understand the final characteristics of coffee beans. Following a description of the coffee fruit tissues, this review presents some data concerning biochemical, enzymatic and gene expression variations observed during the coffee fruit development. The latter will also be analyzed in the light of recent data (electronic expression profiles) arising from the Brazilian Coffee Genome Project.
3
Povilus, Rebecca A., Pamela K. Diggle, and William E. Friedman. "Evidence for parent-of-origin effects and interparental conflict in seeds of an ancient flowering plant lineage." Proceedings of the Royal Society B: Biological Sciences 285, no. 1872 (February 7, 2018): 20172491. http://dx.doi.org/10.1098/rspb.2017.2491.
Full textAbstract:
Theoretical and empirical studies have long connected the evolutionary innovation of endosperm, a genetically biparental product of a double fertilization process unique to flowering plants (angiosperms), to conflicting parental interests over offspring provisioning. Yet, none of these studies examined interparental conflict in representatives of any of the most ancient angiosperm lineages. We performed reciprocal interploidy crosses in the water lily Nymphaea thermarum , a member of one of the most ancient angiosperm lineages, Nymphaeales. We find that an excess of paternal genomes is associated with an increase in endosperm growth. By contrast, maternal ploidy negatively influences development or growth of all seed components, regardless of paternal genome dosage. Most relevant to the conflict over distribution of maternal resources, however, is that growth of the perisperm (seed storage tissue derived from the maternal sporophyte, found in all Nymphaeales) is unaffected by paternal genome dosage—ensuring maternal control of maternal resources. We conclude that the evolutionary transfer of embryo-nourishing function from a genetically biparental endosperm to a genetically maternal perisperm can be viewed as an effective maternal strategy to recapture control of resource distribution among progeny, and thus that interparental conflict has influenced the evolution of seed development in this ancient angiosperm lineage.
4
Liu, Kun, Jerry M. Baskin, Carol C. Baskin, and Guozhen Du. "Very fast-germinating seeds of desert species are cryptoviparous-like." Seed Science Research 23, no. 3 (May 29, 2013): 163–67. http://dx.doi.org/10.1017/s0960258513000135.
Full textAbstract:
AbstractFrom previously published studies we have learned that very fast-germinating species have some characteristics in common with cryptoviviparous species: (1) little or no endosperm/perisperm; (2) embryos fully developed and chlorophyllous at seed maturity; and (3) very fast germination, independent of temperature. Thus, we propose that these very fast-germinating seeds are ‘cryptoviviparous-like′.
5
Mohana Rao, P. R., J. L. Guignard, and S. Duret. "An ultrastructural study of perisperm and endosperm inSilene albaMiller E.H.L. Krause." Bulletin de la Société Botanique de France. Lettres Botaniques 135, no. 2 (January 1988): 123–30. http://dx.doi.org/10.1080/01811797.1988.10824789.
Full text
6
Baskin, Carol C., and Jerry M. Baskin. "Martin's peripheral embryo – unique but not a phylogenetic ‘orphan’ at the base of his family tree: a tribute to the insight of a pioneer seed biologist." Seed Science Research 29, no. 3 (September 2019): 155–66. http://dx.doi.org/10.1017/s0960258519000175.
Full textAbstract:
AbstractAs a tribute to A.C. Martin's classic work on embryos in seeds, we have attempted to gain a better understanding of the peripheral embryo, which puzzled Martin. The peripheral embryo is strongly curved and in contact with the inner surface of the seed coat, and Martin placed it at the base of his family tree of seed phylogeny and called it a ‘phylogenetic orphan’. We evaluated ovule/seed development, kind of embryo and occurrence of perisperm in families with and without a peripheral embryo. All families with a peripheral embryo occur in the Caryophyllales. Seeds with a peripheral embryo have a low cotyledon width:radicle width ratio that coincides with Martin's (full-sized) linear embryo. The peripheral embryo develops in campylotropous and/or amphitropous ovules and is pushed to the side of the seed as the perisperm develops. Linear-full embryos and perisperm are widely distributed across extant angiosperms but are rarely found together, except in core Caryophyllales. The non-core Caryophyllales with endosperm and various kinds of embryos, including the linear-full, diverged before the core Caryophyllales. Thus, the ancestral linear-full embryo appears to have been retained when the core lineage developed campylotropous and/or amphitropous ovules and perisperm. Seeds with a peripheral embryo merit a position on Martin's family tree; however, the position should be a side branch (‘orphan’) slightly above (more advanced than) his linear embryo and not at the base. We conclude that Martin had great insight into the relationships between the kinds of embryos and rightly questioned the position of the peripheral embryo.
7
García-Villanueva, Eduardo, and E. Mark Engleman. "Ontogenia de la semilla de Yucca periculosa (Agavaceae)." Botanical Sciences, no. 61 (May 20, 2017): 5. http://dx.doi.org/10.17129/botsci.1534.
Full textAbstract:
Seeds of several Yucca species have been studied by Arnott and Horner. They mainly studied the nature condition and stated that the extra-embryonic food reserve tissue is a perisperm. This paper provides ontogenic evidence that this tissue is an endosperm with nuclear development type. The seed shape is nearly a triangular prism less than 1 cm long, black color and the raphe groove is conspicuous. The seed coat is derived exclusively from the outer integument. The exotesta external periclinal cell wall appears with irregular thickness. Both mesotesta and endotesta grow irregularly inward the seed confering to the endosperm a ruminate appearance. Toward seed maturity, the inner integument tissues disappear, thus fusion between intertegumentary and tegmen-nucellar cuticles occurs; valuable ontogenic information is showed by the cuticles, due to its persistence in spite of its generative tissue disappearance. The embryo development increases until 10 weeks after anthesis, it is cylindric, folds like "S" and two thirds of its chalazal lenght correspond to the cotyledon.
8
RAMAKRISHNA, P., and DILIP AMRITPHALE. "The Perisperm-endosperm Envelope in Cucumis: Structure, Proton Diffusion and Cell Wall Hydrolysing Activity." Annals of Botany 96, no. 5 (July 25, 2005): 769–78. http://dx.doi.org/10.1093/aob/mci234.
Full text
9
Amritphale, Dilip, P. Ramakrishna, Bharat Singh, and Santosh K. Sharma. "Solute permeation across the apoplastic barrier in the perisperm–endosperm envelope in cucumber seeds." Planta 231, no. 6 (April 1, 2010): 1483–94. http://dx.doi.org/10.1007/s00425-010-1146-5.
Full text
10
Hernández-García, Gricelda, and Eduardo García-Villanueva. "Anatomía compararada de óvulos y semillas de dos especies del género Mammillaria (Cactaceae)." Botanical Sciences, no. 51 (April 24, 2017): 25. http://dx.doi.org/10.17129/botsci.1395.
Full textAbstract:
Flowers and fruits in different developmental stages of Mammillaria rhodantha Link & Otto and M. compressa De Candolle were collected to study the ovule and seed ontogeny. Microscopic slides were made by common techniques. The ovules are campylotropous, crassinucellate and bitegmic. The nucellar curvature of M. rhodantha is 130º and its micropylar curvature is 25º. The funiculus nearly surrounds the ovule and has no trichomes. In M. compressa the nucellar curvature is 90º and its micropylar curvature is Oº. The funiculus is long and surrounds the ovule incompletely or not at all. Trichomes are present on the ventral side. The embryo is curved in both species, 40" in M. rhodantha and 8º in M. compressa. The food reserve tissues are: perisperm and endosperm. The seed coat is formed from endotegmen and exotesta.
11
Friedman, William E., Julien B. Bachelier, and José I. Hormaza. "Embryology inTrithuria submersa(Hydatellaceae) and relationships between embryo, endosperm, and perisperm in early-diverging flowering plants." American Journal of Botany 99, no. 6 (June 2012): 1083–95. http://dx.doi.org/10.3732/ajb.1200066.
Full text
12
Amritphale, Dilip, Koichi Yoneyama, Yasutomo Takeuchi, P. Ramakrishna, and Dai Kusumoto. "The modulating effect of the perisperm–endosperm envelope on ABA-inhibition of seed germination in cucumber." Journal of Experimental Botany 56, no. 418 (June 27, 2005): 2173–81. http://dx.doi.org/10.1093/jxb/eri217.
Full text
13
Salanenka, Yuliya A., Martin C. Goffinet, and Alan G. Taylor. "Structure and Histochemistry of the Micropylar and Chalazal Regions of the Perisperm–endosperm Envelope of Cucumber Seeds Associated with Solute Permeability and Germination." Journal of the American Society for Horticultural Science 134, no. 4 (July 2009): 479–87. http://dx.doi.org/10.21273/jashs.134.4.479.
Full textAbstract:
The perisperm–endosperm (PE) envelope surrounding the embryo of cucumber (Cucumis sativus) acts as a barrier to apoplastic permeability and radicle emergence. The envelope consists of a single cell layer of endosperm whose outer surface is covered by noncellular lipid and callose-rich layers. We compared the structure and histochemistry of the radicle tip and chalazal regions of the envelope, because these regions differ in permeability. Seeds were treated with coumarin 151, a nonionic, fluorescent tracer with systemic activity. Treated seeds were imbibed and on seedcoat removal, the root tip area of the membrane-covered embryo accumulated the fluorescent tracer, but the tracer could not penetrate the envelope that bordered the cotyledons and chalazal region. The cone-shaped remnant of tissue opposite the micropylar region of the envelope was identified as nucellar tissue, the “nucellar beak.” The cuticular membrane and callose layer of the PE envelope were interrupted in the nucellar beak as well as in the chalazal region. Their role in permeability is apparently substituted by the presence of thick-walled suberized cells in the beak and chalaza. A canal was observed in the center of the nucellar beak that likely provided a conduit for the tracer to diffuse from the environment to the embryo. This canal was the remnant of pollen tube entry through the nucellus and was plugged with several cells, presumably residue of the suspensor. These cells degenerated just before cucumber seed germination. This remnant of the pollen tube canal presumably offers less mechanical resistance in the nucellar beak that might help facilitate radicle protrusion during germination. Cells of the outermost and basal regions of the nucellar beak as well as the walls of endosperm cells contained pectic material. Significant pectin methylesterase activity was found in the lateral and cap regions of the PE envelope long before seed germination. Lack of callose in the envelope at the radicle tip suggests that callose does not act as a barrier to radicle emergence during cucumber seed germination.
14
WANG, LIU, YUN-YUN ZHAO, and JIA-XI LIU. "Embryology of Myosoton and Stellaria and its taxonomic significance (Caryophyllaceae)." Phytotaxa 306, no. 2 (May 9, 2017): 124. http://dx.doi.org/10.11646/phytotaxa.306.2.2.
Full textAbstract:
The systematic relationship between the genera Myosoton and Stellaria is a currently controversial. In this study, we compared their embryological characteristics of these two taxa using conventional paraffin section techniques and scanning electron microscopy. The results obtained showed that Myosoton and Stellaria share some common features. They all have tetrasporangiate anthers with dicotyledonous wall, secretory tapetum, microspore mother cells with simultaneous cytokinesis, tetrahedral tetrad, 3-celled mature pollen grains, linear megaspore tetrad, monosporic polygonum embryo sac, ovary with axial placenta at early development stage, secondary free central placenta at mature stage, bitegmic, crassinucellate amphitropous ovule, micropyle formed from inner integument, caryophyllad embryogenesis, nuclear endosperm, and seed with perisperm. In addition, their seed morphologies are also very similar. Both have rounded, polygonal seed coat cells with upward protrudings, V-shaped margin of testa cells and cross-intercellular contacts. The embryological characteristics support that genus Myosoton should be merged into genus Stellaria.
15
Martínez-Colín, Marco A., E. Mark Engleman, and Stephen D. Koch. "Contribución al conocimiento de Peperomia (Piperaceae): fruto y semillas." Botanical Sciences, no. 78 (June 3, 2017): 83. http://dx.doi.org/10.17129/botsci.1722.
Full textAbstract:
Peperomia Ruiz et Pavón comprises an indetermined number of species distributed in tropical and subtropical regions of both hemispheres. One reason for interest in this genus is the difficulty of determining its species. Microscopic features were studied for fruit and seed of 17 Mexican Peperomia species representing six subgenera (Acrocarpidium, Micropiper, Ogmocarpidium, Rhyncophorum, Sphaerocarpidium, and Tildenia). Results show that all 17 materials can be distinguished by fruit characters. The differences among fruits are: (a) location and insertion of fruit on rachis, (b) ovary form, (c) curvature, (d) celular composition in exocarp and endocarp, (e) style form, (f) stigma position, (g) presence of crystals in the pericarp, and (h) dermal cuticle ornamentation. New taxonomic characters are reported, and common terms concerning the insertion and appearance of the fruit are clarified. The seeds of all these species have voluminous perisperm, scarce endosperm, and an undeveloped embryo. Fruit characters in Peperomia can be useful for identifying the species of this genus. However, a thorough search in more species is suggested for additional characters or character states.
16
Xue, Chun-Ying, Hong Wang, and De-Zhu Li. "Female gametophyte and seed development in Musella lasiocarpa (Musaceae), a monotypic genus endemic to Southwestern China." Canadian Journal of Botany 85, no. 10 (October 2007): 964–75. http://dx.doi.org/10.1139/b07-101.
Full textAbstract:
Musella is a monotypic genus composed of a single species, Musella lasiocarpa (Franch.) C.Y. Wu ex H.W. Li, endemic to Southwestern China. The genus status of Musella remains controversial. Musella had been placed first in Musa , then in Ensete , and back to Musa before its monotypic status was recognized. Musella was reported to be extinct in the wild and maintained through cultivation only via vegetative propagation through sprouting of rhizomes. In this study, female gametophyte and seed development of Musella are described to assess its systematic position and possible reasons why the wild population is now extinct. The ovules are anatropous, bitegmic, and crassinucellar. The micropyle is formed by both integuments. The megaspore mother cell undergoes meiotic division and forms a linear megaspore triad or more rarely, a T-shaped megaspore tetrad. The chalazal megaspore develops into a Polygonum type embryo sac. A nucellar pad forms, and a hypostase differentiates. Fertilization is porogamous. Endosperm formation is of the nuclear type. The zygote degenerates and so the process by which the embryo develops, if it does, remains unclear. An operculum, micropylar collar, and chalazal chamber form in mature seeds. The storage tissue is mainly endosperm containing large, compound starch grains and some perisperm. The seed coat has lignified exotestal cells, 25–30 cell layers of sclerotic mesotestal cells, and unspecialized endotesta cells; the tegment consists of two layers of longitudinally elongated cells. The seed is inviable. After comparison with the other Musaceae s. str. taxa using embryological and botanical features, we conclude that Musella should be a distinct genus. Female sterility in Musella may be the main reason why the wild population is extinct. Based on these findings, we propose conservation strategies for this endemic species, including habitat protection as well as ex-situ conservation.
17
Sreenivasulu, Y., and Dilip Amritphale. "Changes in protein composition in cellular membranes of various parts of secondary dormant cucumber seeds treated with ethanol." Seed Science Research 10, no. 1 (March 2000): 61–70. http://dx.doi.org/10.1017/s0960258500000076.
Full textAbstract:
AbstractSecondary seed dormancy in cucumber (Cucumis sativus L.) cv.Poinsett 76 could be broken with ethanol. Breakage of dormancy was accompanied by significant changes in the composition of membrane proteins in various seed parts. Compared to the intracellular membranes, a change in the protein composition of plasma membranes from the embryonic axis and cotyledons was evident early in the time-course of ethanol-induced germination of dormant seeds. While few alterations in the membrane protein composition in response to ethanol treatment occurred both in dormant and nondormant seeds, a number of changes occurred exclusively in ethanol-treated dormant seeds. Notably, a 14 kD protein in the plasma membrane from the embryonic axis and a 35 kD protein in the microsomal membranes from the perisperm-endosperm envelope disappeared in the ethanol-treated dormant seeds, but not in the ethanol-treated nondormant seeds. Also marked decrease in the content of a 23 kD protein in the plasma membrane from the cotyledons was observed in ethanol-treated dormant seeds only. It is suggested that the particular changes in cellular membrane proteins, which occurred in ethanol-treated dormant seeds much before the first visible indication of germination, might be related to dormancy breaking rather than to the germination process.
18
Koshiro, Yukiko, Mel C. Jackson, Riko Katahira, Ming-Li Wang, Chifumi Nagai, and Hiroshi Ashihara. "Biosynthesis of Chlorogenic Acids in Growing and Ripening Fruits of Coffea arabica and Coffea canephora Plants." Zeitschrift für Naturforschung C 62, no. 9-10 (October 1, 2007): 731–42. http://dx.doi.org/10.1515/znc-2007-9-1017.
Full textAbstract:
Chlorogenic acids are major secondary metabolites found in coffee seeds. The accumulation of chlorogenic acids and free quinic acids was studied in Coffea arabica cv. Tall Mokka and Coffea canephora seeds. Growth stages are specified from I to V, corresponding to rapid expansion and pericarp growth (I), endosperm formation (II), mature (green) (III), ripening (pink) (IV), and fully ripened (red) (V) stages. We detected monocaffeoylquinic acids (3CQA, 4CQA and 5CQA), dicaffeoylquinic acids (3,4diCQA, 3,5diCQA and 4,5diCQA) and a monoferuloylquinic acid (5FQA) in whole fruits (stage I), pericarps and seeds. The most abundant chlorogenic acid was 5CQA, which comprised 50-60% of the total of C. arabica and 45-50% of C. canephora seeds. The content of dicaffeoylquinic acid, mainly 3,5d diCQA, was high in C. canephora. A high content of 5FQA was found in seeds of stages III to V, especially in C. canephora. Total chlorogenic acids were accumulated up to 14 mg per fruit in C. arabica and 17 mg in C. canephora, respectively. In contrast, free quinic acid varied from 0.4-2.0 mg (C. arabica) and 0.2-4.0 mg (C. canephora) per fruit during growth. High biosynthetic activity of 5CQA, which was estimated via the incorporation of [U-14C]phenylalanine into chlorogenic acids, was found in young fruits (perisperm and pericarp) in stage I, and in developing seeds (endosperm) in stages II and III. The biosynthetic activity of chlorogenic acids was clearly reduced in ripening and ripe seeds, especially in C. canephora. Transcripts of PAL1, C3′H and CCoAMT, three genes related to the chlorogenic acid biosynthesis, were detected in every stage of growth, although the amounts were significantly less in stage V. Of these genes, CCoAMT, a gene for FQA biosynthesis, was expressed more weakly in stage I. The transcript level of CCoAMT was higher in seeds than in pericarp, but the reverse was found in PAL1. The pattern of expression of genes for the CQA and FQA synthesis is roughly related to the estimated biosynthetic activity, and to the accumulation pattern of chlorogenic acids.
19
Gardarin, Antoine, Françoise Coste, Marie-Hélène Wagner, and Carolyne Dürr. "How do seed and seedling traits influence germination and emergence parameters in crop species? A comparative analysis." Seed Science Research 26, no. 4 (December 2016): 317–31. http://dx.doi.org/10.1017/s0960258516000210.
Full textAbstract:
AbstractEarly plant establishment through seed germination and seedling emergence is a crucial process that determines seedling number, emergence time distribution and the early growth of seedlings, all of which are affected by soil climate and soil structure. In the current context of climate change, in which increasing the diversity of cultivated species is considered desirable, and new tillage practices are considerably modifying top-soil surface characteristics, we need to improve our ability to model the effects of the environment on plant establishment. Using a trait-based and model-based framework, we aimed to identify general relationships between seed and seedling traits (e.g. seed mass and lipid content, seedling diameter, base temperature) and germination and emergence model parameters (e.g. time to mid-germination, shoot elongation rate) measured for 18 genotypes belonging to 14 species. Relationships were also investigated among model parameters or traits. Germination rates were faster for species with a high base temperature and for species with seed reserves located principally in the embryo (rather than the endosperm or perisperm). During heterotrophic growth, maximal shoot length and elongation rate increased with seed dry mass. The sensitivity of seedlings to soil obstacles was negatively related to shoot diameter. Thus apart from the known effects of seed mass on seedling establishment, we found that seed reserve location, seedling shoot diameter and shape affected germination rate and emergence success. Such generic rules linking plant traits to germination and emergence parameters enhance our understanding of the determinants of environmental effects on plant establishment success.
20
Kellmann-Sopyła, Wioleta, Justyna Koc, Ryszard J. Górecki, Marcin Domaciuk, and Irena Giełwanowska. "Development of generative structures of polar Caryophyllaceae plants: the Arctic Cerastium alpinum and Silene involucrata, and the Antarctic Colobanthus quitensis." Polish Polar Research 38, no. 1 (March 1, 2017): 83–104. http://dx.doi.org/10.1515/popore-2017-0001.
Full textAbstract:
AbstractThe embryology of three polar flowering plants of the family Caryophyllaceae was studied using the methods and techniques of the light, normal and fluorescence microscopes, and the electron microscopes, scanning and transmission. The analyzed species wereColobanthus quitensisof West Antarctic (King George Island, South Shetlands Islands) as well asCerastium alpinumandSilene involucrataof the Arctic (Spitsbergen, Svalbard). In all evaluated species, flowering responses were adapted to the short Arctic and Australian summer, and adaptations to autogamy and anemogamy were also observed. The microsporangia of the analyzed plants produced small numbers of microspore mother cells that were differentiated into a dozen or dozens of trinucleate pollen grains. The majority of mature pollen grains remained inside microsporangia and germinated in the thecae. The monosporous Polygonum type (the most common type in angiosperms) of embryo sac development was observed in the studied species. The egg apparatus had an egg cell and two synergids with typical polarization. A well-developed filiform apparatus was differentiated in the micropylar end of the synergids. In mature diaspores of the analyzed plants of the family Caryophyllaceae, a large and peripherally located embryo was, in most part, adjacent to perisperm cells filled with reserve substances, whereas the radicle was surrounded by micropylar endosperm composed of a single layer of cells with thick, intensely stained cytoplasm, organelles and reserve substances. The testae of the analyzed plants were characterized by species-specific primary and secondary sculpture, and they contained large amounts of osmophilic material with varied density. Seeds ofC. quitensis,C. alpinumandS. involucrataare very small, light and compact shaped.
21
Medina, Edison Cardona, Marisa Santos, and Rubens Onofre Nodari. "Post-seminal structure and development of the hemiparasitic plant Escobedia grandiflora (Orobanchaceae)." Acta Scientiarum. Biological Sciences 41 (November 6, 2019): e46667. http://dx.doi.org/10.4025/actascibiolsci.v41i1.46667.
Full textAbstract:
Escobedia grandiflora (L.f.) Kuntze is a wild hemiparasitic plant with orange roots. Little is known about the development of initial parasitism with the host, despite the significant value of roots for Central and South American communities. Therefore, this study aimed to characterize post-seminal structure and development of E. grandiflora in Pennisetum purpureum host. To analyze the structure and development of E. grandiflora, seedlings, stems and roots samples were processed and examined under light, confocal and scanning electron microscopy. Escobedia grandiflora seeds are composed of seed coat, perisperm, and embryo. Emergence of the radicle began eleven days after imbibition. Seedlings showed a root hair collar encircling the axis at the root-hypocotyl junction with elongation of internal cortical cells. Seedlings formed haustoria and successfully reached of the host roots 22 days following root emergence. In the root many starch grains were observed, albeit more scarce in the hypocotyl. After 43 days of root emergence, the seedling stage was finished with the formation of the definitive leaves, and star of the plant stage. After 64 days, root ramification, amount of starch, and orange pigmentation increased with formation of haustoria. The developmental pattern of E. grandiflora plants was slow, but the roots grew faster than the stem. Escobedia grandiflora seeds were not endospermic and have limited nutritional value. After root emergence, the young seedling must develop roots and starch storage towards to haustorium formation and attachment to host roots.
22
Dutta, B., U. Avci, M. G. Hahn, and R. R. Walcott. "Location of Acidovorax citrulli in Infested Watermelon Seeds Is Influenced by the Pathway of Bacterial Invasion." Phytopathology® 102, no. 5 (May 2012): 461–68. http://dx.doi.org/10.1094/phyto-10-11-0286-r.
Full textAbstract:
Watermelon seeds can become infested by Acidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) of cucurbits via penetration of the ovary pericarp or by invasion of the pistil. This study investigated the effect of these invasion pathways on A. citrulli localization in seeds. Seed samples (n = 20 or 50 seeds/lot) from pistil- and pericarp-inoculated lots were dissected into testa, perisperm-endosperm (PE) layer, and embryo tissues and tested for A. citrulli by species-specific polymerase chain reaction (PCR) and by plating on semiselective media. Less than 8% of the testa samples were A. citrulli-positive regardless of the method of seed inoculation. Additionally, the difference in percentages of contaminated testae between the two seed lot types was not significant (P = 0.64). The percentage of A. citrulli-positive PE layer samples as determined by real-time PCR assay was significantly greater for seeds from pistil-inoculated lots (97%) than for seeds from pericarp-inoculated lots (80.3%). The mean percentage of A. citrulli-positive embryo samples was significantly greater for seeds from pistil-inoculated lots (94%) than for seeds from pericarp-inoculated lots (≈8.8%) (P = 0.0001). Removal of PE layers and testae resulted in a significant reduction in BFB seed-to-seedling transmission percentage for seeds from pericarp-inoculated lots (14.8%) relative to those from pistil-inoculated lots (72%). Additionally, using immunofluorescence microscopy, A. citrulli cells were observed in the PE layers and the cotyledons of pistil-inoculated seeds but only in the PE layers of pericarp-inoculated seeds. These results suggest that pericarp invasion results in superficial contamination of the testae and PE layers while pistil invasion results in the deposition of A. citrulli in seed embryos.
23
MIRMAKHMUDOVNA ALIKARIEVA, DURDONA. "MORPHOLOGICAL AND ANATOMICAL FEATURES OF THE STRUCTURE OF VEGETATIVE AND GENERATIVE ORGANS OF LYCIUM CHINENSE MILL. AND LYCIUM BARBARUM L. SOLANACEAE JUSS. IN THE CONDITIONS OF UZBEKISTAN." RA JOURNAL OF APPLIED RESEARCH 08, no. 02 (February 17, 2022). http://dx.doi.org/10.47191/rajar/v8i2.12.
Full textAbstract:
The characteristics of Lycium chinense Mill and Lycium barbarum L., species, taxonomy, origin and use in medicineare given. The adaptation of these plants in the conditions of the Botanical Garden of Tashkent, as well as in the conditions of the Namangan region, was studied. The morphological and anatomical structures of two species of the genus Lycium have been studied. The morphology and structure of vegetative and generative organs, which differ from each other in leaf shape and venation, are described. Leaf cells are studied in detail: the epidermis of the upper side has a smaller number of stomata, which makes it possible to reduce the evaporation of water in summer drought conditions. The spongy parenchyma is chlorophyllon-bearing. Calcium oxalate was found in palisade and spongy parenchyma cells. Conductive bundles of bicollateral type are numerous, consist of phloem and xylem. The center of the petiole has one vascular bundle with a closed bicollateral type. Parenchymal cells are thin-walled, but some have hydrocytic cells. The petiole of the leaf in a transverse section is of the parenchymal-fascicular type, has numerous parenchymas and vascular bundles. Collenchyma is located under the epidermis, based on osmotic phenomena. The stems are sclerified, helping to resist various environmental influences. It was found that with age, the cambium changes the anatomical structure of the stem, and also annually produces secondary xylem.The fruit of Lyciumchinense is a berry, syncarpous and 2-celled. Nucleoli were found in the epidermis. On a transverse section, the pericarp consists of several parenchymal cells, the walls of the epidermis are thickened and cutinized. The mesocarp consists of multi-row parenchymal cells. They are tangentially elongated in the outer layers, and rounded in the inner ones. Endocarp of irregular shape. The seeds of Lyciumchinense are large, round, and have a beak-shaped rib. The cells of the outer epidermis become lignified over time. The parenchyma of the intigument is enclosed between the epidermis. The perisperm is absent. The endosperm is of a cellular type, the endosperm cells contain oil droplets and aleurone grains. Based on the results, morphological-anatomical-histological features were determined. The data obtained can serve to identify plant materials, in environmental studies, as well as to determine diagnostic features.
24
Das, Rajat, Prosanta Pal, and Sonam Bhutia. "Pharmacognostical characterization and formulation of herbal-based low-cost mosquito repellents from Elettaria cardamomum (Linn.) seed by using natural binder." Future Journal of Pharmaceutical Sciences 7, no. 1 (January 11, 2021). http://dx.doi.org/10.1186/s43094-020-00166-3.
Full textAbstract:
Abstract Background In the present scenario, the markets are flooded with chemical-based mosquito repellent products that are proven to be toxic to the human life especially to the children and quite expensive in term of cost. This present investigation was attempted to evaluate the complete pharmacognostical characteristics of Elettaria cardamomum (Linn.) seed and to formulate eco-friendly and cost-effective herbal mosquito repellents of the seed powder by using a natural binder. Results The results of microscopic study of seed confirmed the presence of perisperm, embryo, endosperm and testa (Figs. 4, 5 and 6). The extractive values, moisture contents and ash values were also analysed and found to be alcoholic extract, 4.88% w/w; water extract, 40% w/w; moisture content, 8.6%; total ash, 5% w/w; acid insoluble ash, 1.5% w/w; and water soluble ash, 3.5% w/w (summarized in Tables 1, 2 and 3). From the mosquito repellency test (Table 6), the combination of cardamom seed cake was done with cardamom powder 3/2 + 1/4 spoons, wood powder 3 spoons and chilli powder 1/4 spoon which showed low residual percentage of 15.05%, no irritation and an average burning time of 65 min. The formulated herbal-based mosquito repellents were found to be more effective without any side effects and found less cost too. Conclusion All the ingredients used in the formulation were herbal based and has no side effect on human health. The cost of the cake was Rs. 11.332/- and it can be considered as good mosquito repellent cakes because of its consistent burning ability with no irritating smoke and low residual percentage and high mosquito repellent ability. By utilizing this concept, the researchers can develop herbal, eco-friendly and cost-effective mosquito repellents in future.