Developmental morphology of ovules and seeds of Austrobaileyales

2003 ◽  
Vol 51 (5) ◽  
pp. 555 ◽  
Author(s):  
Toshihiro Yamada ◽  
Ryoko Imaichi ◽  
Nallamilli Prakash ◽  
Masahiro Kato
Keyword(s):  
Seed Development ◽  
Outer Integument ◽  
Developmental Morphology ◽  
Basal Angiosperms ◽  
Mechanical Tissue

Development of ovules of Illicium anisatum (Illiciaceae), Trimenia moorei (Trimeniaceae), and Austrobaileya scandens (Austrobaileyaceae) (Austrobaileyales) was observed. In Austrobaileya scandens and Trimenia moorei the outer integument is hood-shaped, while it is cup-shaped in Illicium anisatum. On the basis of a phylogeny, the ovule with the hood-shaped outer integument is suggested to be primitive in Austrobaileyales. Seed development of Austrobaileyales was also examined. In Austrobaileya scandens the seed is mesotestal, ruminated, not pachychalazal, and has a micropyle–hilum complex. In Trimenia moorei the seed is exotestal, perispermous, not pachychalazal, and has a micropyle–hilum complex and a circular cap. The seed of Illicium anisatum is exotestal, not pachychalazal, and has a circular cap. Taking the character states of other basal angiosperms into account, primitive seeds of angiosperms are inferred to have such characters as the unilayered exotestal mechanical tissue, circular cap, micropyle–hilum complex and non-pachychalazy. The inferred primitive seed is very simple, suggesting that a great diversity of seeds is established through elaboration of organs/tissues of seeds, and not through reduction as hypothesised previously.

scholarly journals Seed development in Paeonia ostii (Paeoniaceae), with particular reference to embryogeny

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Keliang Zhang ◽  
Weizhang Cao ◽  
Jerry M. Baskin ◽  
Carol C. Baskin ◽  
Jing Sun ◽  
...  
Keyword(s):  
Seed Development ◽  
Seed Coat ◽  
Soluble Sugars ◽  
Outer Integument ◽  
Dry Mass ◽  
Endosperm Development ◽  
Raw Material ◽  
Lack Of Information ◽  
Two Stages ◽  
Peripheral Cells

Abstract Background Seeds of Paeonia ostii have been proposed as a source of raw material for the production of edible oil; however, lack of information about the developmental biology of the seeds hampers our ability to use them. Our aim was to investigate development of the seed coat, endosperm and embryo of P. ostii in relation to timing of accumulation of nutrient reserves from pollination to seed maturity. Ovules and developing seeds of P. ostii were collected at various stages of development from zygote to maturity. Seed fresh mass, dry mass, germination, moisture, soluble sugars, starch, protein and oil content were determined. Ontogeny of seeds including embryo, endosperm and seed coat were analyzed histologically. Results The ovule of P. ostii is anatropous, crassinucellate and bitegmic. The zygote begins to divide at about 5 days after pollination (DAP), and the division is not accompanied by cell wall formation. By 25 DAP, the proembryo begins to cellularize. Thereafter, several embryo primordia appear at the surface of the cellularized proembryo, but only one matures. Endosperm development follows the typical nuclear type. The seed coat is derived from the outer integument. During seed development, soluble sugars, starch and crude fat content increased and then decreased, with maximum contents at 60, 80 and 100 DAP, respectively. Protein content was relatively low compared with soluble sugars and crude fat, but it increased throughout seed development. Conclusions During seed development in P. ostii, the seed coat acts as a temporary storage tissue. Embryo development of P. ostii can be divided into two stages: a coenocytic proembryo from zygote (n + n) that degenerates and a somatic embryo from peripheral cells of the proembryo (2n → 2n). This pattern of embryogeny differs from that of all other angiosperms, but it is similar to that of gymnosperms.

scholarly journals Seed Biology of Lepidium apetalum (Brassicaceae), with Particular Reference to Dormancy and Mucilage Development

Plants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 333
Author(s):  
Keliang Zhang ◽  
Yin Zhang ◽  
Yusong Ji ◽  
Jeffrey L. Walck ◽  
Jun Tao
Keyword(s):  
Seed Development ◽  
Seedling Growth ◽  
Seed Coat ◽  
Outer Integument ◽  
Effective Control ◽  
Cold Stratification ◽  
Anatomical Changes ◽  
Seed Biology ◽  
Physiological Dormancy

Lepidium apetalum (Brassicaceae) is an annual or biennial weed widely distributed in Asia and Europe. The outer surface of L. apetalum seeds produces a large amount of mucilage. The primary aim of this study was to explore the dormancy characteristics and to determine how mucilage develops. The role of mucilage in water absorption/dehydration, the effects of after-ripening, gibberellin acid (GA3), cold stratification and seed coat scarification on germination, the role of mucilage in germination and seedling growth during drought, and the progress of mucilage production during seed development were investigated. The results indicate that the best temperature regime for germination was 10/20 °C. After-ripening, GA3 and seed coat scarification helped to break dormancy. Light promoted germination. Seedling growth of mucilaged seeds were significantly higher than those of demucilaged seeds at −0.606 and −1.027 MPa. Anatomical changes during seed development showed that mucilage was derived from the outer layer of the outer integument cells. Our findings suggest that seeds of L. apetalum exhibited non-deep physiological dormancy. The dormancy characteristics along with mucilage production give seeds of L. apetalum a competitive advantage over other species, and thus contribute to its potential as a weed. Effective control of this weed can be achieved by deep tillage.

scholarly journals Anatomía del desarrollo de la semilla de Hippocratea celastroides

2017 ◽  
pp. 43
Author(s):  
Guadalupe Espinosa-Osornio ◽  
E. Mark Engleman
Keyword(s):  
Seed Development ◽  
Outer Integument ◽  
Endosperm Development ◽  
Taxonomic Position ◽  
Early Stages ◽  
Hippocratea Celastroides

Embryological studies of Hippocratea are restricted to few species, and they show similarity between Hippocratea and Celastraceae. Nevertheless, differences based on H. grahamii have originate controversy on the taxonomic position of the genus. We have examined the seed development of H. celastroides H.B.K, by ligth microscopy. This specie has anatropous and bitegmic ovules. At anthesis, the micropyle is formed only by the inner integument. In the endotegmen and exotesta there are tannin deposits beginning in early stages. After fertilization, the outer integument increases abundantly, it alone forms the wing. The endosperm development is of the nuclear type. After syngamy the zygote rests for 3 months before dividing. The mesoteste develops aerenquima, which differentiates gradually into tracheoidal cells. One layer of endosperm remains at madurity. The cotyledons are connate and rotate 90°. On the basis of these results, we consider that Hippocratea belongs the Celastraceae.

scholarly journals Semi-permeable layer formation during seed development in Elymus nutans and Elymus sibiricus

2013 ◽  
Vol 82 (2) ◽  
pp. 165-173 ◽  
Author(s):  
Jing Zhou ◽  
Yanrong Wang ◽  
Jason Trethewey
Keyword(s):  
Seed Development ◽  
Seed Coat ◽  
Outer Integument ◽  
Formation Time ◽  
Original Form ◽  
Elymus Sibiricus ◽  
Permeable Layer ◽  
Transmission Electron ◽  
Sudan Iii ◽  
External Water

<p>The semi-permeable layer is a layer in the seeds of certain plants that restricts or impedes the exchange of the solute while allowing the permeability of internal and external water and gas, which is valuable protection to sustain the health and secure the growth, development and germination. In this study, the formation time and location of the semi-permeable layer in seed coats of <em>Elymus nutants</em> (Griseb.) and <em>Elymus sibiricus</em> (L.) were investigated. The experimental seed materials were gathered in the field from the flowering to seed maturation. The light microscopy and transmission electron microscopy for lanthanum nitrate identification were used to examine the characteristics of pericarp, seed coat and nucellus. The results showed that the semi-permeable layer was identified as the position, which can inhibit the penetration of the lanthanum, and it was checked as an amorphous membrane located at the outermost layer of the seed coat that is firmly attached to the seed coat. With seed development, the cells had differentiated and some parts of the ovary and the outer integument had disappeared. The semi-permeable layer originated from the outer layer of the inner integument, which was the original form of the seed coat. It can be stained by the Sudan III and clearly distinguished from other parts of the seed. The formation time of the semi-permeable layer in both species was nearly at 10 to 12 days post-anthesis (dpa), whereas seed physiological maturity was 24 to 26 dpa.</p>

Morphology of the outer integument in three primitive angiosperm families

1995 ◽  
Vol 73 (8) ◽  
pp. 1242-1249 ◽  
Author(s):  
Ryoko Imaichi ◽  
Masahiro Kato ◽  
Hiroshi Okada
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Outer Integument ◽  
Developmental Morphology ◽  
Primitive Angiosperms ◽  
Primitive State ◽  
Scanning Electron ◽  
Cananga Odorata

Scanning electron microscope examinations were performed to characterize the developmental morphology of the outer integument in several species of the three families Annonaceae (Cananga odorata var. fruticosa, Goniothalamus macrophyllus, and Stelechocarpus burahol), Eupomatiaceae (Eupomatia laurina), and Winteraceae (four Tasmannia species). In all species examined, the inner integument arises as an annular ring, but the outer integument initiates as a semiannular outgrowth interrupted on the concave side of the funiculus; the outer integument then becomes hood-shaped. The inner integument overtops the outer one at maturity, and the micropyle consists only of an endostome. Data from the present and previous studies support the hypothesis that the outer integument is hood-shaped in magnolialean angiosperms and that the bilaterally symmetrical, bladelike outer integument is homologous with the ovuliferous sporophyll of the glossopterids. The micropyle consisting of an endostome might be in a primitive state, compared with a bistomic one. Key words: developmental morphology, integument, micropyle, phylogenesis, primitive angiosperms, scanning electron microscopy.

Abnormalities of Seed Development in a Parthenocarpic Japanese Persimmon, Diospyros kaki cv. Hiratanenashi

1990 ◽  
Vol 59 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Masashi ISHIDA ◽  
Masami KONISHI ◽  
Akira KITAJIMA ◽  
Yoshitsugu SOBAJIMA
Keyword(s):  
Seed Development ◽  
Diospyros Kaki ◽  
Japanese Persimmon
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