Seed germination In Acacia auriculiformis: developmental aspects

1988 ◽  
Vol 66 (2) ◽  
pp. 388-393 ◽  
Author(s):  
P. Pukittayacamee ◽  
A. K. Hellum

Germination of Acacia auriculiformis A. Cunn. ex Benth. seeds was related to seed development. Full physiological development of seeds, indicated by maximum seed dry weight, was reached 82 days after anthesis; however, maximum percent germination was not reached before day 89. Later, germination declined gradually as dormancy and mortality increased. Most seeds were capable of germination without pretreatment at the time of collection, indicating that seed coats were not impermeable to water. Germination of seeds with moisture content from 14 to 29% can be achieved. Anatomical studies revealed that seeds reached maturity after compressing the parenchyma cells against the inside of the seed coat. The physical properties of the seed coat, therefore, did not control its permeability to water. After the developmental period, seed dormancy increased by further drying of seeds during storage.

2001 ◽  
Vol 126 (4) ◽  
pp. 1688-1697 ◽  
Author(s):  
Joost T. van Dongen ◽  
Ramon G.W. Laan ◽  
Madeleine Wouterlood ◽  
Adrianus C. Borstlap

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3833
Author(s):  
Fatma M. Elessawy ◽  
Albert Vandenberg ◽  
Anas El-Aneed ◽  
Randy W. Purves

Pulse crop seed coats are a sustainable source of antioxidant polyphenols, but are typically treated as low-value products, partly because some polyphenols reduce iron bioavailability in humans. This study correlates antioxidant/iron chelation capabilities of diverse seed coat types from five major pulse crops (common bean, lentil, pea, chickpea and faba bean) with polyphenol composition using mass spectrometry. Untargeted metabolomics was used to identify key differences and a hierarchical analysis revealed that common beans had the most diverse polyphenol profiles among these pulse crops. The highest antioxidant capacities were found in seed coats of black bean and all tannin lentils, followed by maple pea, however, tannin lentils showed much lower iron chelation among these seed coats. Thus, tannin lentils are more desirable sources as natural antioxidants in food applications, whereas black bean and maple pea are more suitable sources for industrial applications. Regardless of pulse crop, proanthocyanidins were primary contributors to antioxidant capacity, and to a lesser extent, anthocyanins and flavan-3-ols, whereas glycosylated flavonols contributed minimally. Higher iron chelation was primarily attributed to proanthocyanidin composition, and also myricetin 3-O-glucoside in black bean. Seed coats having proanthocyanidins that are primarily prodelphinidins show higher iron chelation compared with those containing procyanidins and/or propelargonidins.


2007 ◽  
Vol 55 (6) ◽  
pp. 618 ◽  
Author(s):  
Kim N. Hamilton ◽  
Sarah E. Ashmore ◽  
Rod A. Drew ◽  
Hugh W. Pritchard

Combinational traits of seed size and seed-coat hardness in Citrus garrawayi (F.M.Bailey) (syn. of Microcitrus garrowayi) were investigated as markers for estimation of seed morphological and physiological maturity. Seed size (length) and coat hardness correlated well with changes in seed coat and embryo morphological development, dry-weight accumulation, decreases in moisture content and a significant increase in germinability. Seed moisture content decreased from 82 ± 1% in immature seeds to 40 ± 1% at seed maturation. The outer integument of immature seeds consisted of thin-walled epidermal fibres from which outgrowths of emerging protrusions were observed. In comparison, mature seed coats were characterised by the thickening of the cell walls of the epidermal fibres from which arose numerous protrusions covered by an extensive mucilage layer. Immature seeds, with incomplete embryo and seed-coat histodiffereniation, had a low mean germination percentage of 4 ± 4%. Premature seeds, with a differentiated embryonic axis, were capable of much higher levels of germination (51 ± 10%) before the attainment of mass maturity. Mature seeds, with the most well differentiated embryonic axis and maximum mean dry weight, had the significantly highest level of germination (88 ± 3%).


2017 ◽  
pp. 7
Author(s):  
Victoria Hernández-Hernández ◽  
Teresa Terrazas ◽  
Klaus Mehltreter

The root, rhizome, petiole and blade anatomy of Ctenitis melanosticta was studied and compared with the available information for closely related genera. Root is diarc with sclerenchyma and parenchyma cells in the cortex, with fungal hyphae exclusively in the latter. The occurrence of sclereid nests in the rhizome is shared with Dryopteris and Campyloneurum. A cortical band was present in petiole and lamina, as in Dryopteris and other genera of the most derived ferns. The lamina had unifacial mesophyll and under the adaxial epidermis there were several layers of the fiber, as described for Elaphoglossum and Thelypteris, but differed from Asplenium, Dryopteris, and Polybotrya with collenchyma. The anatomy of C. melanosticta was similar to that of most species studied of Dryopteridaceae, although with some differences. Additional anatomical studies in species of Dryopteridaceae will allow to confirm the diagnostic value of several anatomical features, such as the lack of cortical band in the rhizome, the sclereid nests, the unifacial mesophyll, and the cortical band in the lamina.


2018 ◽  
Vol 10 (10) ◽  
pp. 88 ◽  
Author(s):  
Maya Subedi ◽  
Lope G. Tabil ◽  
Albert Vandenberg

Efficient milling is the key economic trait for the red lentil industry. Various seed characteristics including seed coat color can influence milling characteristics. Four basic seed coat ground colors (green, gray, tan, and brown) of 16 red lentil genotypes from a common genetic background were compared to determine the effect of seed coat color genes on three key milling quality traits: dehulling efficiency (DE), milling recovery (MR), and football recovery (FR). These genotypes were grown at two locations in Saskatchewan, Canada for two years. DE, MR, and FR results varied depending on the seed coat color conferred by specific genotypes. Green and gray seed coat color (homozygous recessive tgc allele) genotypes had significantly higher DE and MR percentages compared to brown or tan seed coat types (homozygous dominant Tgc allele) depending on genotype interaction with site-year. Seeds with brown or tan seed coats had significantly higher FR percentages in two site-years. Red cotyledon lentils with uniform shape and green or gray seed coat color might be more profitable for millers who wish to maximize DE and MR of red lentil, but brown seed coat color might be preferable in terms of FR.


Author(s):  
A. S. Timchenko ◽  
A. N. Sorokin ◽  
N. S. Zdravchev ◽  
A. V. F. Ch. Bobrov ◽  
M. S. Romanov

The seed coat anatomy of Wollemia nobilis W. G. Jones, K. D. Hill et J. M. Allen was carried out. In theresult of analysis of transverse sections of seeds the sufficient parenchymatization of seed coats and their differentiationinto three morphogenetic zones – the exotesta, the mesotesta and the endotesta was revealed. Such characters of thespermoderm as differentiation of the mesotesta into several topographic zones, presence of resin cavities in mesotesta, aswell as the participation of both exotesta and mesotesta in making the wing are treated as the archaic ones. The seeds of W.nobilis are of transitional type between exomesotestal and the exotestal type (according to Corner's typology). In generalthe seed coat structure of W. nobilis fits into the divercity of seed coats structure in the family Araucariaceae and is treatedas a progressive type within the family.


2015 ◽  
Vol 25 (3) ◽  
pp. 267-275 ◽  
Author(s):  
Diana Ceccato ◽  
Daniel Bertero ◽  
Diego Batlla ◽  
Beatriz Galati

AbstractTwo possible sources of resistance to pre-harvest sprouting were evaluated in quinoa. They showed dormancy at harvest and significant variations in dormancy level in response to environmental conditions experienced during seed development. The aims of this work were to evaluate the importance of seed coats in the regulation of dormancy in this species, to investigate possible mechanisms of action and to assess association of seed coat properties with changes in dormancy level caused by the environment. Accessions Chadmo and 2-Want were grown under field conditions on different sowing dates during 2 years. Seed coats were manipulated and seed germination was evaluated at different temperatures. Seed coat perforation before incubation led to faster dormancy loss in both accessions. This effect decreased with delayed sowing date, and seeds expressed a level of dormancy not imposed by coats. This suggests the presence of embryo dormancy in the genus Chenopodium. Seeds of the accession 2-Want had a significantly thinner seed coat at later sowing dates, associated with a decreasing coat-imposed dormancy, but this pattern was not detected in Chadmo. The seed coat acts as a barrier to the release of endogenous abscisic acid (ABA) in quinoa, suggested by the increase in germination and a higher amount of ABA leached from perforated seeds. ABA is able to leach from seeds with an intact seed coat, suggesting that differences in seed coat thickness may allow the leakage of different amounts of ABA. This mechanism may contribute to the observed differences in dormancy level, either between sowing dates or between accessions.


1990 ◽  
Vol 38 (2) ◽  
pp. 121 ◽  
Author(s):  
GN Batianoff ◽  
RD Reeves ◽  
RL Specht

Stackhousia tryonii Bailey, which appears to be endemic to the serpentinite soils of the Port Curtis district, central Queensland, is a hyper-accumulator of nickel. Concentrations of this element reach 1-20% of the dry weight of the leaves and 0.1-1% in other parts of the plant. This is the first discovery of such behaviour in a plant from eastern Australia. S. tryonii is easily distinguishable from the Queensland occurrences of a related species, S. monogyna Labill., by its smaller inflorescences and muchbranched, tufted, slender stems and distinctive sparsely tuberculate seed coat. S. monogyna shows no abnormal nickel accumulation. Detailed diagnostic comparative descriptions of S. tryonii and S. monogyna are provided, and notes are given on the ecology and distribution of the two species.


Weed Science ◽  
1978 ◽  
Vol 26 (1) ◽  
pp. 32-36 ◽  
Author(s):  
J. Segura ◽  
S. W. Bingham ◽  
C. L. Foy

The phytotoxicity of glyphosate [N-(phosphonomethyl) glycine] on seeds (protected or non-protected with soil) and seedlings of Italian ryegrass(Lolium multiflorumLam.) and red clover(Trifolium pratenseL.) was studied in the greenhouse. Percent germination of Italian ryegrass seeds covered with soil was significantly reduced with glyphosate applied at 4 kg/ha. The direct treatment over the seeds on the soil surface was more toxic, reducing the number of established seedlings at dosages of 3 and 4 kg/ha. In the two red clover seed treatments, germination was significantly reduced with 2 kg/ha of herbicide. Even though germination was reduced at intermediate rates of glyphosate, shoot growth and tillering were improved and yields of dry weight were equivalent to that of untreated plants. Postemergence applications of glyphosate were phytotoxic to both species with the effects becoming more pronounced at increasing dosages. However, at equal dosage, red clover was less susceptible than Italian ryegrass. The patterns of foliar absorption and translocation of14C from14C-glyphosate was similar in Italian ryegrass and red clover.14C was translocated throughout the plants and exhibited apoplastic and symplastic movement.


1997 ◽  
Vol 73 (4) ◽  
pp. 453-457 ◽  
Author(s):  
R. A. Lautenschlager

Red raspberry (Rubus idaeus L.) seeds germinate only after seed coats are degraded. In nature this happens slowly. Seeds from recently collected fruit (fresh to four years old) germinated only after scarification of the seed coat by 20-minute soaking in concentrated sulfuric acid. Germination was not enhanced by: (1) short-term intermittent soaking, up to 81 hours, in dilute (0.01 normal) hydrochloric acid; (2) passage through the digestive tracts of bears, coyotes, or birds; (3) physical perturbations such as nicking, mechanical scarification, repeated freezing and thawing and/or four years of exposure in the field; (4) exposure to light; (5) increased temperatures or temperature fluctuations; or (6) addition of nitrogen (ammonium nitrate, urea). Key words: animal passage, germination, nitrogen, red raspberry, Rubus idaeus L., seed coat, seed weight, scarification, stratification


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