Germination of Seeds From the Fruits of Thryptomene calycina (Myrtaceae)

1993 ◽  
Vol 41 (2) ◽  
pp. 263 ◽  
Author(s):  
DV Beardsell ◽  
RB Knox ◽  
EG Williams
Keyword(s):  
Gibberellic Acid ◽  
Sulphuric Acid ◽  
Seed Coat ◽  
Major Site ◽  
Low Concentrations ◽  
Viable Seeds ◽  
Insect Predation

Freshly fallen fruits of T. calycina contained seeds which were completely dormant; none germinated after 200 days at 20°C. Seeds excised with testas intact from fresh fruits were partially dormant; one-third germinated after 60 days. The dormancy of seeds in freshly fallen fruits was imposed jointly by the fruit and the seed. The major site of the dormancy was however the seed coat since tearing part of it away from seeds excised from fresh fruits resulted in rapid and complete germination. Fruits stored dry in a laboratory at 20°C for 90 days were partially dormant. Nicking the distal end of these fruits enhanced germination. Seeds excised from these laboratory stored fruits had 85 % germination, which indicated a reduction in the seed imposed dormancy. Germination of T. calycina was independent of light and, although the fruits contained large amounts of phenolic material this did not inhibit germination. Fruits weathered in the field for at least 2 years contained less viable seeds, presumably because of insect predation, but these all germinated within 50 days at 20°C. Brief washing of fruits in concentrated sulphuric acid increased germination. Germination was not enhanced by treatment with low concentrations of gibberellic acid in the presence or absence of cytokinin.

Initiation and morphological development of somatic embryoids from barley cell cultures

1984 ◽  
Vol 62 (6) ◽  
pp. 1245-1249 ◽  
Author(s):  
L. S. Kott ◽  
K. J. Kasha
Keyword(s):  
Somatic Embryogenesis ◽  
Abscisic Acid ◽  
Gibberellic Acid ◽  
Cell Cultures ◽  
Dichlorophenoxyacetic Acid ◽  
Morphological Development ◽  
Low Concentrations ◽  
The Media ◽  
2,4 Dichlorophenoxyacetic Acid ◽  
Barley Cell

Somatic embryogenesis was induced in callus previously initiated from immature embryos of barley. These cultures ranged in age from 6 weeks to 30 months. Embryoids were readily initiated from homogenized suspension-grown aggregates when plated on modified B5 media with 2,4-dichlorophenoxyacetic acid. Low concentrations (0.1 and 0.05 mg∙L−1) of abscisic acid promoted further maturation of embryoids, while gibberellic acid (1 mg∙L−1) and kinetin (0.1 mg∙L−1) were used in the media to encourage embryoid germination. The development of somatic embryoids from initiation through maturation and germination is described.

scholarly journals Scarification with sulphuric acid of Schizolobium amazonicum Huber ex Ducke seeds - FABACEAE

2007 ◽  
Vol 64 (3) ◽  
pp. 308-313 ◽  
Author(s):  
Eniel David Cruz ◽  
José Edmar Urano de Carvalho ◽  
Rafaela Josemara Barbosa Queiroz
Keyword(s):  
Statistical Analysis ◽  
Experimental Design ◽  
Seed Germination ◽  
Sulphuric Acid ◽  
Seed Coat ◽  
Immersion Time ◽  
Germination Index ◽  
Efficient Treatment ◽  
Tukey Test

Seed coat impermeability to water occurs in many species, including Schizolobium amazonicum Huber ex Ducke. To promote germination in seeds with coat impermeability the use of sulphuric acid (H2SO4) is recommended. The objective of this study was to identify a better time for the scarification with sulphuric acid for S. amazonicum seeds. The effect of scarification with sulphuric acid for 20, 40 and 60 min on germination and speed germination was studied for seeds that were either sowed immediately after scarification or after a 24-hour period of immersion in water. Seeds were sown on a mix of sand and sawdust (1:1). The experimental design was completely randomized with four replications of 50 seeds. The statistical analysis of germination was carried out at six, nine, 12, 15, 18, 21 and 24 days after sowing, in a factorial scheme. For speed germination the means were compared by the Tukey test. There was an interaction between treatments to overcome dormancy and immersion time after scarification in most evaluations. Immersion in water accelerated the beginning of germination. All treatments to overcome dormancy promoted seed germination. However, scarification for 60 min, showed better germination, 92% when immediately sown and 86.5% when sown after 24 hours. Speed germination index was highest for scarified seeds for 60 min followed by immersion in water. Scarification for 60 min was the most efficient treatment to promote germination in S. amazonicum seeds.

scholarly journals Improving germination of Prunus avium L. seeds by gibberellic acid, potassium nitrate and thiourea

2011 ◽  
Vol 33 (No. 3) ◽  
pp. 119-123 ◽  
Author(s):  
M. Çetinbaş ◽  
F. Koyuncu
Keyword(s):  
Gibberellic Acid ◽  
Seed Coat ◽  
Prunus Avium ◽  
Potassium Nitrate ◽  
A Value ◽  
Prunus Avium L

To break dormancy and increase the germination of Prunus avium L. (mazzard cherry) seeds, various methods were tested including the removal of the seed coat after cold moist stratification and treatment with GA<sub>3</sub>, KNO<sub>3</sub>, or thiourea. Treatments with 7,500 ppm KNO<sub>3</sub> after 120 days of stratification were more effective, yielding 64.54% germination of seeds with coat. In seeds without coat, 500 ppm GA<sub>3</sub> treatment after 120 days of stratification gave 79.74% germination; a value increased about 29% compared to control. &nbsp;

scholarly journals Role of the Seed Coat in Dormancy of Eucalyptuspauoiflora and E. Delegatensis Seeds

1967 ◽  
Vol 20 (6) ◽  
pp. 1237 ◽  
Author(s):  
EP Bachelard
Keyword(s):  
Gibberellic Acid ◽  
Seed Coat ◽  
Gaseous Exchange ◽  
Eucalypt Species ◽  
Phacelia Tanacetifolia

Gibberellic acid promotes the germination of dormant seeds of some eucalypt species including Eucalyptus pauciflora Sieb. and E. delegatensis R. T. Baker. It was suggested that gibberellic acid may stimulate germination by promoting enzymatic weakening of the seed coat (Bachelard 1967) as described for Phacelia tanacetifolia seeds (Chen and Thimann 1964). Previously, Grose (1963) suggested dormancy of of E. delegatensis seeds might be due to the seed coat limiting gaseous exchange.

scholarly journals Seed Germination of selected Taxa from Kachchh Desert, India

2010 ◽  
Vol 2 (2) ◽  
pp. 41-45 ◽  
Author(s):  
Vinay Madhukar RAOLE ◽  
Aruna Girish JOSHI ◽  
Sandhya Kiran GARGE ◽  
Rinku Jitendrakumar DESAI
Keyword(s):  
Seed Germination ◽  
Growth Regulators ◽  
Seed Coat ◽  
Native Species ◽  
Arid Regions ◽  
Conservation Status ◽  
Storage Period ◽  
The Other ◽  
Viable Seeds ◽  
Semi Arid

The district of Kachchh contains many culturally important plants. However, their conservation status is little known due to direct and indirect human activities. This study was undertaken with the aim of contributing to the conservation of the native species of these semi-arid regions through germination trials under laboratory conditions. Mature fruits of ten selected species were collected randomly from the known habitats to obtain viable seeds. These seeds were pre-treated with growth regulators singly or in combination after acid scarification or without scarification. Seeds were found to be dormant due to presence of thick seed coat or due to low level of endogenous hormonal level. Most of these seeds required different storage period to mature. Only seeds of Capparis cartilaginea germinated without treatment while the other species required treatments. Addition of growth regulators has enhanced seed germination in few taxa singly and in some plant cases in combination.

scholarly journals Physiochemical Studies of Sodium Chloride on Mungbean (Vigna radiataL. Wilczek) and Its Possible Recovery with Spermine and Gibberellic Acid

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Srijita Ghosh ◽  
Sanglap Mitra ◽  
Atreyee Paul
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Gibberellic Acid ◽  
Chlorophyll Content ◽  
Biomass Production ◽  
Oxidative Stress Marker ◽  
Antioxidant Enzyme Activities ◽  
Oxidative Stress Markers ◽  
Stress Markers ◽  
Low Concentrations

The physiological and biochemical responses to increasing NaCl concentrations, along with low concentrations of gibberellic acid or spermine, either alone or in their combination, were studied in mungbean seedlings. In the test seedlings, the root-shoot elongation, biomass production, and the chlorophyll content were significantly decreased with increasing NaCl concentrations. Salt toxicity severely affected activities of different antioxidant enzymes and oxidative stress markers. Activities of antioxidant enzymes, superoxide dismutase (SOD), and catalase (CAT) increased significantly over water control. Similarly, oxidative stress markers such as proline, malondialdehyde (MDA), and hydrogen peroxide (H2O2) contents also increased as a result of progressive increase in salt stress. Combined application of NaCl along with low concentrations of either gibberellic acid (5 µM) or spermine (50 µM) in the test seedlings showed significant alterations, that is, drastic increase in seedling elongation, increased biomass production, increased chlorophyll content, and significant lowering in all the antioxidant enzyme activities as well as oxidative stress marker contents in comparison to salt treated test seedlings, leading to better growth and metabolism. Our study shows that low concentrations of either gibberellic acid or spermine will be able to overcome the toxic effects of NaCl stress in mungbean seedlings.

Dormancy, germination and seedling growth of two Kalaharian perennials of the genus Harpagophytum (Pedaliaceae)

1988 ◽  
Vol 4 (2) ◽  
pp. 185-198 ◽  
Author(s):  
W. H. O. Ernst ◽  
T. Tietema ◽  
E. M. Veenendaal ◽  
R. Masene
Keyword(s):  
Gibberellic Acid ◽  
High Temperatures ◽  
Seedling Growth ◽  
Seed Coat ◽  
Growth Rates ◽  
Natural Conditions ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Respiration Rates ◽  
Drought Avoidance

ABSTRACTDormancy and germination ecology of two Harpagophytum species (Pedaliaceae) from an open Acacia savanna in Botswana were investigated. The maintenance of dormancy is governed partly by the seed coat but mainly by the endosperm and the embryo itself, as demonstrated by removal of the endosperm. Dissemination of the seed from the fruit can be delayed for several years without affecting the viability of the embryo, due to very low respiration rates.Germination can be enhanced slightly by high temperatures under natural conditions, and by gibberellic acid or removal of the endosperm under laboratory conditions. Relative growth rates for both Harpagophytum species are lower than for subtropical grasses and legumes, due to a strong investment in root and tuber biomass. Germination and seedling growth is discussed in relation to the drought avoidance syndrome and the animal disperser syndrome.

scholarly journals Changes in the Raman spectrum of sulphuric acid on dilution

1934 ◽  
Vol 144 (851) ◽  
pp. 129-143 ◽  
Keyword(s):  
Sulphuric Acid ◽  
Raman Effect ◽  
Wave Length ◽  
Frequency Shifts ◽  
Low Concentrations ◽  
Intensity Changes ◽  
Continuous Background ◽  
Length Determination ◽  
Detailed Interpretation ◽  
Two Stages

The results of previous workers upon the Raman effect of sulphuric acid show a considerable lack of agreement, due no doubt in part to the intensity of the accompanying continuous background and the apparent diffuseness of certain of the lines. Thus both Nisi and Woodward found that change of the concentration of the add greatly modified the appearance of the spectrum, influencing both the positions and the relative intensities of the lines. Wood-ward gave photometer carves of the spectra for concentrations ranging from 100% to 25% by volume, and attributed the observed intensity changes to tho successive stages of ionization of the acid. The lines Δ v = 910 and 1140 cm. -1 (approximate values), which were strong in the 100% acid, became weaker and shifted somewhat as the concentration decreased; while a new line Δ v = 1046 cm. -1 made its appearance and increased correspondingly in intensity. At low concentrations this last line became double, a companion appearing at 982 cm. -1 . The frequencies 910 and 1110 were regarded as characteristic of the H 2 SO 4 molecule, 1016 of the HSO' 4 ion, and 982 of the SO" 4 ion. Other diffuse lines also showed frequency shifts. Bell and Fredrickson. however, whose measurements were made not only with a prism spectrograph but also with a grating, failed to find any appreciable shifts of the line with dilution. Moreover, they stated that on their plates the 1016 line gave no indication of becoming double at low concentrations, but merely grew more diffuse. The findings of other workers are referred to in the discussion of our results (see below). In view of the conflicting nature of the above evidence regarding the two stages of ionisation of the acid, it was thought, desirable to repeat tho investigations using a higher dispersion than that employed by Woodward ( loc. cit .), the object of the work being to obtain more conclusive photometer curves of the spectra. The curves we have actually obtained not only give a clear picture of the intensity changes involved, but have also been used in a rational method of wave-length determination, the adoption of which has made it possible for us to propose a somewhat more detailed interpretation of the spectra than has hitherto been attempted.

The effect of sodium hypochlorite, gibberellic acid, and light on seed dormancy and germination of wild buckwheat (Polygonum convolvulus) and cow cockle (Saponaria vaccaria)

1979 ◽  
Vol 57 (16) ◽  
pp. 1735-1739 ◽  
Author(s):  
A. I. Hsiao
Keyword(s):  
Seed Germination ◽  
Gibberellic Acid ◽  
Sodium Hypochlorite ◽  
Seed Coat ◽  
Inhibitory Effect ◽  
Promoting Effect ◽  
Wild Buckwheat ◽  
Polygonum Convolvulus ◽  
Effect Of Light ◽  
Main Factor

Seed germination of wild buckwheat (Polygonum convolvulus L.) and cow cockle (Saponaria vaccaria L.) increased with increasing time of immersion in 6% sodium hypochlorite (NaOCl). Maximum germination was obtained at 6 to 8 h for wild buckwheat and at 2 h for cow cockle. The effect of NaOCl treatment of wild buckwheat seeds mimics the effect of acid scarification. Wild buckwheat germination was not influenced by light and (or) gibberellic acid (GA3). To induce 50% germination (t½) of cow cockle NaOCl treatments of 0.5 and 1 h were required for seeds incubating in the dark and light, respectively. Once the seed coat was made more permeable by NaOCl, both the promoting effect of GA3 and the inhibitory effect of light were increased. When the optimum effect of NaOCl occurred, all the seeds germinated. However, prolonged NaOCl treatment resulted in either poor germination or seed disintegration.The hard coat seems to be the main factor in regulating wild buckwheat seed germination. Cow cockle, however, is regulated by at least two other factors, light and hormones, in addition to seed coat.

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