A NOVEL EFFECT OF UV‐B IN A HIGHER PLANT (<i>SORGHUM VULGARE</i>)

Drumm‐Herrel, H.; Mohr, Hans

doi:10.1111/j.1751-1097.1981.tb05435.x

Cited by 57 publications

(26 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The action of UV-A must be considered to establish responsiveness to Pfr rather than mediating induction of anthocyanin. The same conclusion was drawn with regard to the action of BL on the longitudinal growth of the hypocotyls of sesame seedlings (7). RL absorbed by phytochrome contributes to the state of responsiveness as well, independently of UV-A.…”

Section: Discussionsupporting

confidence: 49%

“…At present it remains an enigma why it requires more than 3 hr before anthocyanin eventually appears. As far as we know at present (5,7,8), responsiveness of a plant towards Pfr always depends on the quality and quantity of the ambient light. A higher plant measures light throughout the spectrum, and this information-obtained via phytochrQme, cryptochrome, and a UV-B photoreceptor (4)-determines the efficiency of Pfr action, or in other words, the actual responsiveness towards Pfr during growth and development of a plant.…”

Section: Discussionmentioning

confidence: 99%

“…Weider (hybrid) were selected, and seedlings were grown at 25 ± 0.5°C as described (8). Standard light fields (7,8) Plexiglas filter to allow the action of a small amount of UV-B (for detailed information about spectral composition, see ref.…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Mode of coaction between blue/UV light and light absorbed by phytochrome in light-mediated anthocyanin formation in the milo ( Sorghum vulgare Pers.) seedling

Oelmüller

Mohr

1985

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Anthocyanin formation in milo (Sorghum vulgare Pers.) seedlings (coleoptile, mesocotyl, taproot) occurs only in white light and blue/UV light (BL/UV), while red light (RL) and far-RL are totally ineffective. However, after a BL/UV pretreatment, the participation of phytochrome can be demonstrated. With a short-wavelength light source [peak emission in longwave UV (UV-A)], the mode of coaction between BL/UV and light absorbed by phytochrome (RL) was studied with the following principal results. (i) As soon as the seedling becomes competent to respond to UV-A (with regard to anthocyanin formation), the involvement of phytochrome can be detected. (it) A 5-min pulse of UV-A has a strong effect on the anthocyanin synthesis in the milo mesocotyl. This effect is fully reversible if a long-wavelength far-RL pulse (RG9 light) is given immediately after the UV-A light pulse. (iii) When seedlings treated with 5 min of UV-A and 5 min of RG9 light are kept in darkness for 3 hr and then transferred to RL, anthocyanin appears. (iv) In continuous UV-A treatment, anthocyanin accumulation starts after a lag phase of 3.5 hr (25°C). A RL pretreatment prior to the onset of UV-A treatment strongly increases anthocyanin accumulation in UV-A, though the lag phase is not affected. Moreover, a RL pretreatment does not affect the time course for escape from reversibility in UV-A. It is concluded from these data that BL/UV cannot mediate induction of anthocyanin synthesis in the absence of Pf,, the active form of phytochrome that absorbs maximally in the far-red. Rather, the action of BL/UV must be considered to establish responsiveness of the anthocyaninproducing mechanism to Pfr. Pfr operates in this system via two different channels. As the effector of the terminal response, it sets in motion the signal-response chain that eventually leads to the appearance of anthocyanin. This is a slow process with a lag phase of the order of 3.5 hr. The second function of Pfr is to determine the responsiveness to the effector Pfr in mediating anthocyanin synthesis. This is a very fast and highly sensitive phytochrome action that can be detected readily within 1 min. However, as long as the plant has not received BL/UV, the strong effect of RL on the effectiveness of Pfr remains cryptic. The effect of a RL pretreatment and the effect of a UV-A pretreatment on responsiveness towards Pfr (or, effectiveness of Pfr) were found to be totally independent ofeach other, even though it is the UV-A that permits operation of Pfr.

show abstract

Section: Discussionsupporting

confidence: 49%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Mode of coaction between blue/UV light and light absorbed by phytochrome in light-mediated anthocyanin formation in the milo ( Sorghum vulgare Pers.) seedling

Oelmüller

Mohr

1985

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Yatsuhashi et al (1982) found that the action of the 385-, 480-, and 650-nm anthocyanin peaks in sorghum was mediated by phytochrome, but not that of the 290-nm peak. Synthesis of anthocyanin and flavone glycoside appears to be mediated by UV-B and phytochrome photoreceptors (Wellmann, 1974;Drumm-Herrel and Mohr, 1981;Duell-Pfaffand Wellmann, 1982). Although both types of photoreceptor sometimes act synergistically, they may also act independent of one another (Yatsuhashi and Hashimoto, 1985).…”

Section: Regulation Of Flavonoid and Isoflavonoid Productionmentioning

confidence: 97%

Effects of Ultraviolet-B Radiation on Terrestrial Plants

Bornman

Teramura

1993

Environmental UV Photobiology

190

138

View full text Add to dashboard Cite

“…The induction of inhibition of hypocotyl elongation and other de-etiolation processes by UV-A light are most probably physiological responses, rather than a result of cell damage. Damage to plants by UV light is primarily limited to wavelengths below 320 nm (Giese 1968;Coohill 1989), and many non-damaging effects have been observed in UV-B as well as UV-A light (Baskin and Iino 1987;Drumm-Herrel and Mohr 1981;Lercari et al 1990). …”

Section: De-etiolation Responses Induced By Uv-amentioning

confidence: 99%

Spectral-dependence of light-inhibited hypocotyl elongation in photomorphogenic mutants of Arabidopsis: evidence for a UV-A photosensor

Young¹,

Liscum²,

Hangarter³

1992

Planta

View full text Add to dashboard Cite

Photon fluence rate-response curves at different wavelengths were generated for the light-induced inhibition of hypocotyl elongation in seedlings of wildtype and photomorphogenic mutants of Arabidopsis thaliana. (L.) Heynh. Treatment of wild-type seedlings with continuous low-fluence-rate light (< 1.0 μmol photons · m(-2) · s(-1)) induced some inhibition of hypocotyl elongation at all wavelengths tested, with maximum inhibition in blue light. At higher fluence rates, inhibition reached a maximum of 70-80% in UV-A, blue, and far-red light. Fluence rate-response curves for seedlings of blu1, a blue light-response mutant, showed a specific reduction in their response to blue light, but their response to UV-A, red, and far-red light was similar to that in wild-type seedlings. In contrast, the phytochromedeficient mutant hy6 showed a loss of response to lowfluence-rate light at all wavelengths, as well as to highfluence-rate far-red light. However, hy6 seedlings retained sensitivity to high-fluence-rate blue and UV-A light. The data support the conclusion that blue-lightand phytochrome-dependent photosensory systems regulate hypocotyl elongation independently and in an additive manner. Furthermore, hypocotyl inhibition in wild-type, blul, hy6 and blul-hy6 double mutants was indistinguishable in UV-A light, whereas marked differences were observed at other wavelengths, indicating the involvement of a third photosensory system with an absorption maximum in the UV-A.

show abstract

A NOVEL EFFECT OF UV‐B IN A HIGHER PLANT (SORGHUM VULGARE)

Cited by 57 publications

References 18 publications

Mode of coaction between blue/UV light and light absorbed by phytochrome in light-mediated anthocyanin formation in the milo ( Sorghum vulgare Pers.) seedling

Mode of coaction between blue/UV light and light absorbed by phytochrome in light-mediated anthocyanin formation in the milo ( Sorghum vulgare Pers.) seedling

Effects of Ultraviolet-B Radiation on Terrestrial Plants

Spectral-dependence of light-inhibited hypocotyl elongation in photomorphogenic mutants of Arabidopsis: evidence for a UV-A photosensor

Contact Info

Product

Resources

About