Wyniki wyszukiwania - Biblioteka Nauki

1

Zaleznosci pomiedzy fotosynteza i oddychaniem u roslin

100%

Poskuta J. W.

Wiadomości Botaniczne

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1992

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tom 36

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nr 3-4

47-52

2

Development of photosynthetic apparatus in etiolated of pea during greening as influenced by toxic concentration of lead

84%

Poskuta J. W. , Lukaszek M.

Acta Physiologiae Plantarum

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1998

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tom 20

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nr 1 suppl.

3

The effect of of cadmium on photosynthesis and respiration in detached leaves Zea mays L.

84%

Kolodynski P. , Poskuta J. W.

Acta Physiologiae Plantarum

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1999

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tom 21

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nr 3 suppl.

4

Oxygen and radioation effects on CO2 echange in light and in darkness of decaploid and hexaploid tall fescue (Festuca arundinacea Schreb.)

84%

Poskuta J. W. , Nelson C. J.

Acta Societatis Botanicorum Poloniae

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1986

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tom 55

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nr 1

5

Chlorophyll a fluorescence kinetics and CO2 exchange rates in light and in darkness in leaves of tall fescue as affected by UV radiation

84%

Lukaszek M. , Poskuta J. W.

Acta Physiologiae Plantarum

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1996

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tom 18

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nr 4

6

Occurence of respiration during photosynthesis in leaves of Setcreasea purpurea Boom and Ficus benjamina L.

84%

Poskuta J. W. , Sojka E.

Acta Physiologiae Plantarum

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1992

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tom 14

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nr 1

7

In vivo responses of primary photochemistry of photosystem II and CO2 exchange in light and in darkness of tall fescue genotypes to lead toxicity

84%

Poskuta J. W. , Waclawczyk-Lach E.

Acta Physiologiae Plantarum

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1995

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tom 17

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nr 3

8

Development of photosynthetic apparatus and respiration in pea seedlings during greening as influenced by toxic concentration of lead

84%

Lukaszek M. , Poskuta J. W.

Acta Physiologiae Plantarum

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1998

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tom 20

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nr 1

EN

Detached leaves of 14 day-old dark-grown pea seedlings were immersed with their cut ends either in water (control) or in 20 mM Pb(NO₃)₂ solution. They were exposed to continuous illumination during 24 and 48 h. The formation of PSII primary photochemistry in thylakoids was determined in vivo by measuring changes in values of parameters of chlorophyll a fast fluorescence kinetics: Fo, Fm, Fv, Fv/Fm and t 1/2. The amount of lead accumulation in leaves, content of chlorophylls and carotenoids and rates of CO₂ uptake in light and evolution in darkness (Pn-net photosynthesis and DR - dark respiration respectively) were determined. It has been found that with the exception of Fo, values of Fv, Fm and Fv/Fm were reduced by Pb²⁺. The values of t 1/2 were significantly larger in Pb²⁺ treated leaves. Decrease in the chlorophyll a fluorescence parameters was paralleled with the strong inhibition by this metal the biosynthesis of chlorophyll a and b but less of the carotenoids. Pb²⁺ drastically reduced Pn but had a stimulatory action on DR after 24 h and small inhibition of DR after 48 h exposure of leaves to this metal. As a consequence, after 48 h of greening the ratio of DR/Pn of control leaves was 0.45 whereas in Pb²⁺ treated leaves 2.7. It is proposed that DR in leaves plays a protective role against damage of Pn by Pb²⁺. Protection can be due to the supply the respiratory derived reductant and ATP to carry out cell metabolism upon reduced photosynthesis.

9

Phoyosynthetic and respiratory cacteristics of Cortaderia pilosa ( D'Urv.Hack) the dominant component of Falkland Islands vegetation adapted to cool and moist climate

67%

Poskuta J. W. , McAdam J. H. , Waclawczyk-Lach E. , Wroblewska B.

Acta Physiologiae Plantarum

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1998

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tom 20

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nr 1 suppl.

10

The effect of lead on the gaseous exchange and photosynthetic carbon metabolism of pea seedlings

67%

Poskuta J. W. , Parys E. , Romanowska E.

Acta Societatis Botanicorum Poloniae

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1987

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tom 56

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nr 1

11

The effect of lead on photosynthesis and respiration in detached leaves and in mesophyll protoplasts of Pisum sativum

67%

Parys E. , Romanowska E. , Siedlecka M. , Poskuta J. W.

Acta Physiologiae Plantarum

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1998

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tom 20

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nr 3

EN

Photosynthesis and transpiration rate of detached leaves of pea (Pisum sativum L. cv. Iłowiecki) exposed to solution of Pb(NO₃)₂ at 1 or 5 mmol·dm⁻³ concentrations were inhibited. The higher concentration of this toxicant decreased photosynthesis and transpiration rates 2 and 3 times respectively, and increased respiration by about 20 %, as measured after 24 hours of treatment. Similarly to Pb(NO₃)₂, glyceraldehyde solution, an inhibitor of phosphoribulokinase, at 50 mmol·dm⁻³ concentration decreased the rates of photosynthesis and transpiration during introduction into pea leaves. The rate of dark respiration, however, remained unchanged during 2 hours of experiment. The potential photochemical efficiency of PS II (Fv/Fm) and the activity of Rubisco (EC 4.1.1.39) at 5 mmol·dm⁻³ of Pb(NO₃)₂ were lowered by 10 % and 20 % respectively, after 24 hours. Neither changes in the activity of PEPC (EC 4.1.1.31) or protein and pigment contents were noted in Pb-treated leaves. The photosynthetic activity of protoplasts isolated from leaves treated for 24 or 48 hours with Pb(NO₃)₂ at 5 mmol·dm⁻³ concentration was decreased 10 % or 25 %, whereas, the rate of dark respiration was stimulated by about 40 % and 75 %, respectively. The content of abscisic acid, a hormone responsible for stomatal closure, in detached pea leaves treated for 24 h with 5 mmol·dm⁻³ of Pb(NO₃)₂ solution was increased by about 3 times; a longer (48h) treatment led to further increase (by about 7 times) in the amount of this hormone. The results of our experiments provide evidences that CO₂ fixation in detached pea leaves, at least up to 24 hours of Pb(NO₃)₂ treatment, was restricted mainly by stomatal closure.

12

Foliar sprays of methanol ineffective in activity of photosystem II, amount of photosynthetic pigments, CO2 exchange in light and in darkness and herbage yield of hexaploid and decaploid tall fescue genotypes

67%

Poskuta J. W. , Parys E. , Waclawczyk-Lach E. , Wroblewska B.

Acta Physiologiae Plantarum

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1995

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tom 17

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nr 1

13

Toxicity of lead to photosynthesis, accumulation of chlorophyll, respiration and growth of Chlorella pyrenoidosa. Protective role of dark respiration

67%

Poskuta J. W. , Parys E. , Romanowska E.

Acta Physiologiae Plantarum

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1996

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tom 18

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nr 2

14

The effects of lead on photosynthesis, 14C distribution among photoassimilates and transpiration of maize seedlings

59%

Poskuta J. W. , Parys E. , Romanowska E. , Gajdzis-Gujdan H. , Wroblewska B.

Acta Societatis Botanicorum Poloniae

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1988

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tom 57

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nr 1