Red Light Inhibition of Spore Germination in Lycopodium clavatum

Spores of Ophioglossum crotalophoroides Walt., which give rise to subterranean, nonphotosynthetic, mycorrhizal gametophytes, germinate in the dark and not in the light. Red light, like white light, prevents the germination of these spores. Germination occurs after exposure to far-red. The effects of far-red light can be reversed by red light and those of red light can be partly reversed by far-red light, confirming the involvement of phytochrome. With the spores of O. crotalophoroides, the active form of phytochrome, Pfr, prohibits germination. The photoinhibition of germination by white or red light insures that these spores germinate underground in nature. Hypogean germination improves the chances for adequate soil moisture and for the young gametophytes to be colonized by mycorrhizal fungi.

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The influence of red and blue light on the rate of photosynthesis and the CO2 compensation point at various oxygen concentrations

Canadian Journal of Botany ◽

10.1139/b70-186 ◽

1970 ◽

Vol 48 (6) ◽

pp. 1251-1257 ◽

Cited By ~ 11

Author(s):

N. P. Voskresenskaya ◽

G. S. Grishina ◽

S. N. Chmora ◽

N. M. Poyarkova

Keyword(s):

Nicotiana Tabacum ◽

Blue Light ◽

Photosynthetic Rate ◽

Prolonged Exposure ◽

Red Light ◽

Compensation Point ◽

Gas Analyzer ◽

Co2 Compensation Point ◽

Rate Of Photosynthesis ◽

Light Inhibition

Apparent photosynthesis of attached leaves of Phaseolus vulgaris, Vicia faba, Pisum sativum, and Nicotiana tabacum at various intensities of blue and red light was measured by infrared CO2 gas analyzer in a closed system. Simultaneously the CO2 compensation point was measured.It was found that light-limited photosynthetic rate in blue light was equal to or more than that in red light. Inhibition of photosynthesis, which sometimes occurred at light-saturated intensities of blue light, could be avoided by addition of red light, prolonged exposure of the plants to blue light, or by lowering the O2 concentration. Accordingly, the increase of photosynthetic rate due to change of O2 concentration from 21 to 3% O2 is higher in blue light only when photosynthesis is inhibited by blue light at 21% O2. The data on the action of blue and red light on the CO2 compensation point seems to exclude the activation of photorespiration by blue light.The possible effects of blue light on apparent photosynthesis are discussed on the basis of the results presented.

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Effects of Anaerobiosis and Respiratory Inhibitors on Blue-Light Inhibition of Spore Germination in Pteris vittata

Plant and Cell Physiology ◽

10.1093/oxfordjournals.pcp.a076456 ◽

1982 ◽

Vol 23 (7) ◽

pp. 1155-1160

Author(s):

Michizo Sugai

Keyword(s):

Blue Light ◽

Spore Germination ◽

Pteris Vittata ◽

Respiratory Inhibitors ◽

Light Inhibition

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The role of the seed coat in the light sensivity in Raphanus sativus L. cv. redondo gigante seeds

Acta Botanica Brasilica ◽

10.1590/s0102-33061997000100006 ◽

1997 ◽

Vol 11 (1) ◽

pp. 55-60

Author(s):

Maura Lúcia Costa Gonçalves ◽

Massanori Takaki

Keyword(s):

Seed Coat ◽

Raphanus Sativus ◽

Red Light ◽

Light Sensitivity ◽

Percentage Germination ◽

Raphanus Sativus L ◽

Light Inhibition ◽

Glycol Solution ◽

High Inhibition

The role of the seed coat in the light sensitivity of seeds of Raphanus sativus L. cv. redondo gigante was analysed by germination tests of intact and naked seeds. Far-red light caused high inhibition of seed germination, while under white and red lights low inhibition was found. Naked seeds presented no light sensitivity with high percentage germination under light and darkness. However, incubation of naked seeds in -0.6MPa polyethylene glycol solution resulted in light inhibition as observed in intact seeds. The analysis of the seed coat transmitted light indicated that the filtered light presented the same photoequilibrium of phytochrome when compared to the white light, with a decrease of only 33% in the light irradiance which reaches the embryo.

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Red/far-red light signals regulate the activity of the carbon-concentrating mechanism in cyanobacteria

Science Advances ◽

10.1126/sciadv.abg0435 ◽

2021 ◽

Vol 7 (34) ◽

pp. eabg0435

Author(s):

Nadav Oren ◽

Stefan Timm ◽

Marcus Frank ◽

Oliver Mantovani ◽

Omer Murik ◽

...

Keyword(s):

Desiccation Tolerance ◽

Inorganic Carbon ◽

Red Light ◽

Negev Desert ◽

Light Perception ◽

Inhibitory Protein ◽

Bisphosphate Carboxylase ◽

Liquid Cultures ◽

Light Inhibition ◽

Light Signals

Desiccation-tolerant cyanobacteria can survive frequent hydration/dehydration cycles likely affecting inorganic carbon (Ci) levels. It was recently shown that red/far-red light serves as signal-preparing cells toward dehydration. Here, the effects of desiccation on Ci assimilation by Leptolyngbya ohadii isolated from Israel’s Negev desert were investigated. Metabolomic investigations indicated a decline in ribulose-1,5-bisphosphate carboxylase/oxygenase carboxylation activity, and this was accelerated by far-red light. Far-red light negatively affected the Ci affinity of L. ohadii during desiccation and in liquid cultures. Similar effects were evident in the non–desiccation-tolerant cyanobacterium Synechocystis. The Synechocystis Δcph1 mutant lacking the major phytochrome exhibited reduced photosynthetic Ci affinity when exposed to far-red light, whereas the mutant ΔsbtB lacking a Ci uptake inhibitory protein lost the far-red light inhibition. Collectively, these results suggest that red/far-red light perception likely via phytochromes regulates Ci uptake by cyanobacteria and that this mechanism contributes to desiccation tolerance in strains such as L. ohadii.

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Photo-Inhibition of Red-Light-Induced Spore Germination in Pteris vittata: Cyanide, Azide and Ethanol Counteracts Restorable Inhibitory Action of Near UV and Blue-light but not That of Far UV

Plant and Cell Physiology ◽

10.1093/oxfordjournals.pcp.a077925 ◽

1990 ◽

Keyword(s):

Blue Light ◽

Spore Germination ◽

Inhibitory Action ◽

Red Light ◽

Pteris Vittata

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Asymmetric cell division and differentiation; fern spore germination as a model. I. Physiological aspects

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000008150 ◽

1985 ◽

Vol 86 ◽

pp. 213-226

Author(s):

John H. Miller

Keyword(s):

Cell Division ◽

Spore Germination ◽

Metal Binding ◽

Asymmetric Cell Division ◽

Red Light ◽

Metal Binding Sites ◽

Sequence Of Events ◽

Cytoplasmic Microtubules ◽

External Stimuli ◽

The Relationship

SynopsisDuring germination of Onoclea sensibilis spores, the spore nucleus moves from a central location to one end. Cell division partitions the spore into a small cell which differentiates into a rhizoid, and a larger cell which gives rise, by continued division, to the prothallus. Spore germination is a valuable system in which to study the relationship between asymmetric cell division and the initiation of cell differentiation. It appears that cytoplasmic microtubules and some lipophilic site in the spore are both involved in premitotic nuclear migration. Asymmetric cell division is an obligate step in the initiation of rhizoid differentiation. One hypothesis is that the nucleus must be confined to a small, localised region of the spore for a sufficient time before differentiation can occur, and the confinement is accomplished by the asymmetric cell division. Metal-binding sites are present in the spore coat, specifically on the proximal face. Several types of evidence suggest that the metal-binding region is involved in spore polarity. The sequence of events during germination appears to involve both polarity which is inherent in the spore and polarity which may be imposed by external stimuli. Experiments in which spores are treated with colchicine and polarised red light reveal both types of polarity.

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