Endogenous α-Ketol Linolenic Acid Levels in Short Day-Induced Cotyledons are Closely Related to Flower Induction in Pharbitis nil

We present the potential involvement of Mg2+ in the flowering mechanism in the shoot apex of the short-day plant Pharbitis nil (L.). To analyze elemental distribution in shoot apical meristems, fluorescence staining methods with Mag-fluo-4 AM and Fluo-3 AM were used. The former is sensitive to both Mg2+ and Ca2+, and the latter is a specific Ca2+ indicator. When plants were grown under continuous light conditions, some cells with intensive fluorescence of Mg2+ appeared in the top layers of the shoot apical meristem. During growth in the vegetative phase, cells in the center of the top layers accumulated large amounts of Mg2+. Exposure to a single 16 h short-day treatment induced the flowering process and dramatically reduced the fluorescence associated with Mg2+ accumulation in the top layers, suggesting that Mg2+ contributes to the flower induction process. The fluorescence associated with Ca2+ did not show this distribution difference between growth phases. A night-break treatment also influenced the fluorescence pattern. It was suggested for the first time that Mg2+ plays an important role in flower induction.

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Changes in Catecholamine Levels in Short Day-Induced Cotyledons of Pharbitis nil

Zeitschrift für Naturforschung C ◽

10.1515/znc-2003-3-414 ◽

2003 ◽

Vol 58 (3-4) ◽

pp. 220-224 ◽

Cited By ~ 3

Author(s):

Masayuki Suzuki ◽

Masaya Mizoguchi ◽

Fumihiko Yano ◽

Utako Hara ◽

Mineyuki Yokoyama ◽

...

Keyword(s):

Continuous Light ◽

Flower Induction ◽

Pharbitis Nil ◽

Fresh Weight ◽

Dark Treatment ◽

Short Day ◽

Dopamine Content ◽

Significant Change ◽

First Time ◽

Catecholamine Levels

We investigated the effects of catecholamine on flower-induction in P. nil (cv. Violet). GCSIM analysis identified dopamine for the first time in P. nil seedlings. Dopamine levels in the cotyledons did not show a significant change during the inducing dark treatment. The dopamine content of cotyledons exposed to various durations of darkness were 0.1-0.2 nmol/ g fresh weight. The same content was found when cotyledons were exposed to continuous light.

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The level of phyA in Pharbitis nil Chois during the photoperiodic flower induction

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2000.035 ◽

2014 ◽

Vol 69 (4) ◽

pp. 269-272 ◽

Cited By ~ 1

Author(s):

Adriana Szmidt-Jaworska ◽

Krzysztof Jaworski ◽

Jan Kopcewicz

Keyword(s):

Dark Period ◽

Polyclonal Antibodies ◽

Flower Induction ◽

Pharbitis Nil ◽

Light Illumination ◽

Direct Control ◽

Short Day ◽

Rapid Destruction ◽

Photoperiodic Flower Induction

The aim of this work was to determine if there is any relationship between an endogenous phyA level and photoperiodic flower induction. The level of phyA was characterised with polyclonal antibodies directed to phyA from pea. At first it was detected that phyA level is predominant in cotyledons, whereas in roots and stems the concentration of labile phytochrome is rather low. So cotyledons were used for later experiments. In these cotyledons exposed to light illumination a rapid destruction of phyA has been observed. The loss of extractable phyA chromoprotein occurs already after 60 min of irradiation. <em>Pharbitis nil</em> is a short-day plant and a single 16-hours-long dark period is fully inductive. We assessed that phyA level is extremely low during a long inductive night and an immunodetectable phytochrome appears only after 24 hours of darkness. The obtained results suggest that labile phytochrome is not taking part in the direct control of the photoperiodic flower induction.

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Effects of carbon dioxide on Pharbitis, Xanthium, and Silene in short days

Canadian Journal of Botany ◽

10.1139/b74-166 ◽

1974 ◽

Vol 52 (6) ◽

pp. 1283-1291 ◽

Cited By ~ 12

Author(s):

A. N. Purohit ◽

E. B. Tregunna

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Concentration ◽

Dry Weight ◽

Morphological Characters ◽

Photoperiodic Response ◽

Pharbitis Nil ◽

Light Sources ◽

Short Day ◽

Unit Leaf ◽

Silene Armeria

The flowering response and other morphological characters of Pharbitis nil, Xanthium pennsylvanicum, and Silene armeria were studied in environments with different levels of carbon dioxide and oxygen under short-day conditions. Different light sources and intensities were also tested. Irrespective of the light source and intensity used, higher levels of carbon dioxide delayed or inhibited flowering as well as other morphological characters of the short-day plants but induced flowering in the long-day plant. Dry weight per unit leaf area as well as total chlorophyll increased with carbon dioxide concentration. The results are discussed in relation to some other recent reports, and it is proposed that large variations in photosynthetic rates of plants probably alter their photoperiodic response.

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Effects of Photoperiodism and Other Factors on the Improvement of Pigeonpea Varieties

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v48i3.12989 ◽

1969 ◽

Vol 48 (3) ◽

pp. 232-235

Author(s):

Arturo Riollano

Keyword(s):

Day Treatment ◽

Breeding Program ◽

Flower Induction ◽

Day Length ◽

Flower Formation ◽

Length Of Day ◽

Short Day ◽

Late Variety ◽

Polyethylene Bags

Studies on the effects of photoperiodism and other factors were conducted to obtain information which might be useful in a breeding program with pigeonpeas. The information was sought for accelerating this work in a region where extremes of day-length vary by only 2 hours because of its location in latitude 18°. By shortening the length of day to 8 hours through the use of a darkroom, and planting during the month of February, it was possible to induce flower formation 4 months earlier in two early varieties and 7 weeks earlier in a late variety. However, this short-day treatment did not appreciably affect the time of flower induction in an all-season, or "Totiempo" variety. One-gallon tin-can containers and 10-inch polyethylene bags were found satisfactory for growing pigeonpea plants of different varieties.

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