Janusz Kościelniak | University of Agriculture in Krakow (original) (raw)

Papers by Janusz Kościelniak

Photosynthetica, 2005

Seedlings of winter rape were cultured in vitro on media containing 24-epibrassinolide, EBR (100 ... more Seedlings of winter rape were cultured in vitro on media containing 24-epibrassinolide, EBR (100 nM) and cadmium (300 µM). After 14 d of growth, fast fluorescence kinetics of chlorophyll (Chl) a and contents of photosynthetic pigments and Cd in cotyledons were measured. Cd was strongly accumulated but its content in cotyledons was 14.7 % smaller in the presence of EBR. Neither Cd nor EBR influenced the contents of Chl a and b and carotenoids. Cd lowered the specific energy fluxes per excited cross section (CS) of cotyledon. The number of active reaction centres (RC) of photosystem 2 (RC/CS) decreased by about 21.0 % and the transport of photosynthetic electrons (ET 0 /CS) by about 17.1 %. Simultaneously, under the influence of Cd, the activity of O 2 evolving centres (OEC) diminished by about 19.5 % and energy dissipation (DI 0 /CS) increased by about 14.6 %. In the cotyledons of seedlings grown on media without Cd, EBR induced only a small increase in the activity of most photochemical reactions per CS. However, EBR strongly affected seedlings cultured with cadmium. Specific energy fluxes TR 0 /CS and ET 0 /CS of the cotyledons of plants Cd+EBR media were about 10.9 and 20.9 % higher, respectively, than values obtained for plants grown with Cd only. EBR also limited the increase of DI 0 /CS induced by Cd and simultaneously protected the complex of OEC against a decrease of activity. Hence EBR reduces the toxic effect of Cd on photochemical processes by diminishing the damage of photochemical RCs and OECs as well as maintaining efficient photosynthetic electron transport.

Journal of Plant Physiology, 2003

Electrical activity (action and variation potentials) and ethylene emission were measured in ther... more Electrical activity (action and variation potentials) and ethylene emission were measured in thermally stimulated Vicia faba minor seedlings. It was determined that variation potential with or without superimposed action potentials was generated and propagated basipetally in response to scorching of the upper leaf. In stimulated plants the level of ethylene production measured in lower, non stimulated leaf was significantly higher than that in the control plants and the difference correlated with the amplitude of the electrical response. Neither variation nor action potential was recorded when ethylene was injected to the chamber covering the experimental leaf. The level of ethylene emission showed clear circadian rhythm when measured at photoperiod 16 : 8 (LD) or at constant light (LL). It is concluded that the sequence of ion fluxes registered as an electrical response of a plant to the thermal stimulus is a signal evoking an enhancement of ethylene emission.

Photosynthetica, 2006

The influence of chilling (8 o C, 5 d) at two photon flux densities [PFD, L = 200 and H = 500 µmo... more The influence of chilling (8 o C, 5 d) at two photon flux densities [PFD, L = 200 and H = 500 µmol(photon) m −2 s −1 ] on the gas exchange and chlorophyll fluorescence was investigated in chilling-tolerant and chilling-sensitive maize hybrids (Zea mays L., K383×K130, K185×K217) and one cultivar of field bean (Vicia faba L. minor, cv. Nadwiślański). The net photosynthetic rate (P N) for the both studied plant species was inhibited at 8 o C. P N of both maize hybrids additionally decreased during chilling. Changes in the quantum efficiency of PS2 electron transport (Φ PS2) as a response to chilling and PFD were similar to P N. Measurements of Φ PS2 /Φ CO2 ratio showed that in field bean seedlings strong alternative photochemical sinks of energy did not appear during chilling. However, the high increment in Φ PS2 /Φ CO2 for maize hybrids can indicate reactions associated with chill damage generation. At 8 o C the non-photochemical quenching (NPQ) increased in all plants with chilling duration and PFD. The appearance of protective (q I,p) and damage (q I,d) components of q I and a decrease in q E (energy dependent quenching) took place. NPQ components of field bean and maize hybrids differed from each other. The amount of protective NPQ (q E + q I,p) components as part of total NPQ was higher in field bean than in maize hybrids at both PFD. On 5 th day of chilling, the sum of q E and q I,p was 26.7 % of NPQ in tolerant maize hybrids and 17.6 % of NPQ in the sensitive one (averages for both PFD). The increased PFD inhibited the ability of all plants to perform protective dissipation of absorbed energy. The understanding of the genotypic variation of NPQ components in maize may have implications for the future selection of plants with a high chilling tolerance.

Journal of Agronomy and Crop Science, 2010

Brassinosteroids are plant steroid hormones important for plant growth and development. They incl... more Brassinosteroids are plant steroid hormones important for plant growth and development. They include more then 70 compounds. Their physiological effect and possibilities of practical use are still being investigated. In this study, we evaluated the effects of exogenously applied 24-epibrassinolide, one of the brassinosteroids, on the grain yield and grain chemical composition (carbohydrates, proteins, fats and minerals) of wheat. Moreover, we analysed the presence of brassinosteroids in newly formed wheat grains after exogenous plant treatment with 24-epibrassinolide. Experiments were performed in a vegetation hall (plants cultivated in pots) and in the field. The tested regulator was applied via 48 h seed soaking (1 mgAEdm)3) or spraying plants at the heading stage (0.25 mgAEdm)3). 24-epibrassinolide increased grain yield in plants growing in the field (by about 20 %), but not in plants cultivated in vegetation hall. Grain chemical composition was altered by 24-epibrassinolide in wheat growing in the vegetation hall; the content of soluble sugars was higher while that of total fats and calcium was lowered, whereas the starch and soluble protein content was not affected. The effect of the hormone was in these cases dependent on the method of its application. As for plants cultivated in the field, the hormone impact on the amount of carbohydrates, proteins, fats and minerals contained in the grains was rather negligible. In wheat grains, the presence of brassinolide, castasterone and 24-epicastasterone was found. 24-Epibrassinolide applied exogenously to plants was not accumulated in newly formed grains. Additionally, significance of ethanol as a hormone solvent is discussed.

Journal of Agronomy and Crop Science, 1995

The relations between the extent of injuries in seedlings caused by a few day-long exposures to c... more The relations between the extent of injuries in seedlings caused by a few day-long exposures to chill (5 o C) and the leakage of K + , Mg 2+ and Ca 2+ ions from the leaves as well as the electric potential in seven maize hybrids, were investigated. The permeability of cells to ions was defined based on their absolute concentration in a water diffusate (C t ) and concentration expressed in relation to the total ion content in the leaves (IL index). At lowered temperature the hybrids of higher resistance to chilling temperature were characterized by a lower value of the IL index for K + and Mg 2+ ions than the chill-sensitive hybrids. On the other hand, absolute concentration of the ions (C t ) Mg 2+ and Ca 2+ leaking from the leaves before chill exposure of the seedlings was positively and highly correlated with the extent of injuries in hybrids caused by 4 day-long exposures to chill. This observation is evidence that the chill injuries were predetermined through increased cell permeability to the mentioned ions at room temperature. Changes in the electric potential of leaves in conditions of lowered temperature preceded the injuries of leaves, which became apparent after a longer period of exposure to chill. Thus, as the leakage of Mg 2+ and Ca 2+ ions occurs, changes in the electric potential may supply early information about the predisposition of the particular maize hybrids to chilling injuries. Leakage measurements of Mg 2+ and Ca 2+ ions from the leaves at room temperature may find application in the selection of chill-tolerant maize genotypes

Journal of Agronomy and Crop Science, 1997

Field beans of indeterminate (cv. Nadwislariski) and determinate (cv. Tibo) growth habits were gr... more Field beans of indeterminate (cv. Nadwislariski) and determinate (cv. Tibo) growth habits were grown on field plots with a density of 20, 40 and 80 plants mat two levels of nitrogen fertilization: low (20 kg N ha~') and very high (150 kg N ha"'). At the phase of intense pod growth the number and the dry matter weight of root nodules as well as their nitrogenase activity and some features of the plants growth were determined, and in the period of ripeness the components of seed yield were established. It was found that increased density of sowing as well as the high level of nitrogen fertilization inhibited the growth and development of root nodules and limited their nitrogenase activity in both cultivars. Plants of both varieties were characterized by a similar potential of forming the root nodules, however, in plants of the cv. Tibo the nitrogenase activity of nodules was much lower than in the cv. Nadwislanski. Increased population density of the plants has in both varieties given increased seed yield when calculated per m-of the soil, compensating in excess the depression of the seed yield from one plant. Such compensation did not occur in the case of the depression of nitrogen fixation under intense nitrogen fertilization.

Journal of Agronomy and Crop Science, 1996

The effect of separate chilling (5 °C for 2 and 4 days) on the shoots and roots of two mai^e hybr... more The effect of separate chilling (5 °C for 2 and 4 days) on the shoots and roots of two mai^e hybrid seedlitigs on the electrsc potential, die composition of fany acids and the ATPase activity in the microsomcs of non-chilled leaves and roots (20 °C) was investigated. It has been found that the low tetnperatuties induced on the non-chilled organs gave similar changes to organs exposed to a reduced temperature. The changes consisted ofa parallel depolarization of leaf and root membranes and simiiarty a decrease in the ATPase activity as well as changes in the unsamratson of the membranes' fatty acids. The reduction of the acid content 18:2 was particularly significant, which in the leaf iJiicrosomes correlated with a drop in the ATPase activity. The similarity between the teactians of the chilled and non-diilled parts of the plant gives evidence of a cominunicaaon' between the organs wWch may facilitate a coordinated reaction of the entire organism to stress. The background for these phenomena couid be the action potential of the chilled parts of seedlings which, in the oon-chilled parts, mig^t produce changes in the structure of biomembranes and in the activity of eniytnes.

Acta Physiologiae Plantarum, 2007

During cold acclimation by higher plants, temperature perception via changes in redox state of Ph... more During cold acclimation by higher plants, temperature perception via changes in redox state of Photosystem II (PSII) and subsequent acclimation of the photosynthetic apparatus to cold is very important for achieving freezing tolerance. These properties were studied in two groups (A and B) of the same backcross 3 (BC 3) progeny derived from a triploid hybrid of Festuca pratensis (2•) • Lolium multiflorum (4•) backcrossed three times onto diploid L. multiflorum cultivars. Leaves of Group A plants formed at 20°C at medium-low light were unable to acclimate their photosynthetic apparatus to cold. Compared to Group B, the Group A plants were also more frost sensitive. This acclimation ability correlated with the freezing tolerance of the plants. However, leaves of the same Group A plants developed at 20°C, but under higher-light conditions had increased ability to acclimate their photosynthetic apparatus to cold. It was concluded that Group A plants may have impaired PSII temperature perception, and this then resulted in their poor capability to cold acclimate.

Australian Journal of Crop Science, Mar 1, 2014

The content of antioxidants (tocopherols, trocotrienols, ascorbic acid, β-carotene) as well as so... more The content of antioxidants (tocopherols, trocotrienols, ascorbic acid, β-carotene) as well as soluble proteins, total fats and soluble sugars were studied in the seeds of pea and lupine after application of brassinosteroid (24-epibrassinolide). Plants were cultured in separate pots in an open vegetation hall in 2010. The following year, a field experiment was carried out in a randomized block design where plants were growing in rows, directly in the soil. 24-Epibrassinolide (0.25-0.5 mg dm-3) was applied via spraying or watering of the flowering plants. Experiments were done during natural vegetation seasons (spring-summer, latitude: 50°03' N, longitude: 19°55' E) and seeds were collected after maturation. In the pea pot experiment, γ-tocopherol content was increased (9%-15%) in seeds after brassinosteroid spraying (0.5 mg dm-3). In the lupine field experiment, αand γ-tocopherol content was elevated in seeds (8%-84%) after brassinosteroid application (0.25 mg dm-3) via both methods. In the pea field and pot experiment, the ascorbic acid content was increased (18-52%) after watering plants with 24-epibrassinolide (0.25 mg dm-3). In lupine seeds, ascorbic acid as well as β-carotene content was elevated after brassinosteroid watering (0.25 mg dm-3). The brassinosteroid effect on the content of proteins, sugars, and fats in seeds was also studied. The results obtained in our study show the possibility of using brassinosteroid to manipulate plant seed content, which may be important from a nutritional point of view. Moreover, the studies reveal some mechanisms of brassinosteroid action on the metabolism of seeds.

Plant Biology, 2013

Festuca arundinacea is a drought tolerant species. Lolium multiflorum has better forage quality b... more Festuca arundinacea is a drought tolerant species. Lolium multiflorum has better forage quality but lower tolerance to abiotic stresses. Their hybrids offer an opportunity to perform research on the molecular basis of tolerance to drought. The aim of this work was to recognise the mechanisms of response to short-term drought (11 days) in a glasshouse in two L. multiflorum/F. arundinacea introgression forms with distinct levels of tolerance to long-term drought (14 weeks) in the field. Measurements of physiological parameters, analyses of protein accumulation profiles using two-dimensional gel electrophoresis, and mass spectrometry identification of proteins, which were accumulated differentially between the selected genotypes during shortterm drought, were performed. Genotype 7/6, with lower yield potential during 14 weeks of drought, and lower ability to re-grow after watering, had a higher capacity for photosynthesis during 11 days of drought. Genotype 4/10, more tolerant to longterm drought, was able to repair damaged cell membranes after watering and was also characterised by lower transpiration during short-term drought. A total of 455 proteins were analysed, and the 17 that were differentially accumulated between the two genotypes were identified. The results of physiological and proteomic research led to a hypothesis that the higher photosynthetic capacity of genotype 7/6 could be due to a more efficient Calvin cycle, supported by higher accumulation of crucial proteins involving chloroplast aldolase.

Journal of Agronomy and Crop Science, 2010

A number of physiological and molecular characteristics are proposed as selection criteria for dr... more A number of physiological and molecular characteristics are proposed as selection criteria for drought tolerance. This study measured the associations between physiological and molecular characteristics of drought response in malting and fodder spring barleys. Plants of 13 malt-and 14 feed-type Polish genotypes were exposed to drought at the four-leaf stage for 7 days. Drought susceptibility indexes (DSI) were calculated for membrane integrity, water status, gas exchange and PSII photochemical activity. Accumulation of HVA1 and SRG6 transcripts in drought was measured with real-time PCR. A wide range of variation in the drought response was observed among studied genotypes. Malting barleys were less sensitive to drought than feed-barleys according to all the traits studied. In both groups, different patterns of relationships between traits were observed. In malting genotypes only, CO 2 assimilation rates in drought, as well as PSII efficiency were related to both water content and the accumulation of HVA1 transcript in leaves. On the other hand the SRG6 expression was highly correlated in both groups of barley with the photochemical efficiency of PSII. The results suggest that different physiological, biochemical and molecular characteristics should be applied in the selection towards drought resistance in the case of malting and fodder barleys.

Acta Physiologiae Plantarum, 2010

The aim of the experiments presented here was twofold. On the one hand, to study the influence of... more The aim of the experiments presented here was twofold. On the one hand, to study the influence of plant growth regulators, i.e. auxins (IAA and NAA), cytokinins (kinetin, zeatin and zeatin riboside), gibberellins: (GA 3) and polyamines (spermidine, spermine and putrescine) on the generative development of winter wheat plants, while on the other to study the interaction of plant growth regulators with electric current in affecting the efficiency of the flowering of wheat plants. Winter wheat var. Grana was subjected to a short vernalization (2 weeks at 5°C ? 10 days at 10°C) on Murashige and Skoog medium containing growth regulators at different concentrations. For Keywords In vitro culture Á Plant growth regulators Á Electric current Á Vernalization Á Winter wheat Communicated by K. Trebacz.

Acta Physiologiae Plantarum, 1998

Murashige & Skoog nutrient was supplemented with subs... more Murashige & Skoog nutrient was supplemented with substances of molecular weight (MW) less than 5 kDa, which were separated from extract of winter wheat ears by means of Sephadex G-25 ultrafiltration. Isolated embryos of the same wheat cultivar (Grana) were vernalized in the nutrient for 0 and 7 days at 2 °C for 2 weeks and planted in a glass-house.

Photosynthetica, 2009

The seeds of soybean cv. Aldana and spring wheat cv. Torka were soaked for 24 h in solution of ze... more The seeds of soybean cv. Aldana and spring wheat cv. Torka were soaked for 24 h in solution of zearalenone [ZEN, 2,4-dihydroxy-6-(10-hydroxy-6-oxo-trans-1-undecenyl)-benzonic acid lactone, 4 mg dm-3 ] and then they were sown in the pot experiment in an open vegetation hall. The after-effects of ZEN on growth of plants, net photosynthetic (P N) and transpiration (E) rates, stomatal conductance (g s), photochemical efficiency of photosystem II (PSII) and on final seeds yield, were determined. A significant increase of seeds yield was revealed in plants of both cultivars i.e. by 22% and 19% of seed (grain) number and by 28 and 24% of seed (grain) mass, in soybean and in wheat, respectively. The photosynthetic rate (P N) was stimulated during the juvenile and final phase by about 13.6% (average) in soybean plants. During other developmental stages, assimilation of CO 2 was retarded. The response of CO 2 assimilation in wheat plants was less pronounced as compared to that in soybean, but an increase of P N by over 24% near the final stage of development was observed. The quantum yield of PSII electron transport (Φ PSII) in soybean plants was changed after the treatment of seeds by ZEN similarly as for the rate of CO 2 , whereas in wheat it continued to gradually increase i.e. during the whole growth period. Changes of Φ PSII both in soybean and in wheat plants, as the response to ZEN treatment, were accompanied with an increase in the efficiency of changes occurring within the antenna (F v '/F m ') as well as within centres of photochemical reactions (q p). The conclusion is that ZEN can affect plant growth and development in many ways, as well as in the status and functioning of the photosynthetical apparatus. Some of the effects can be very longlasting, as e.g. stimulation of production of seed yield in response to treatment of seeds with this substance.

Plant Science, 1997

Damage done to horse bean roots through rapid heating to temperatures above 8O"C, induced the app... more Damage done to horse bean roots through rapid heating to temperatures above 8O"C, induced the appearance of a wave of electric potential which reached the leaves within about 25 s. The passing wave was accompanied by stimulation of the shoot respiration which attained a maximum rate of up to 140-160% of its initial value within 70-80 s after the roots had been heated. Local cooling of the stem (0°C and 2°C) or freezing a section of it with liquid nitrogen, as well as treatment with sodium azide, inhibited the stimulation of respiration, which seems to be a consequence of inhibition and damping of the amplitude of the electric wave reaching the leaves.

Journal of Agronomy and Crop Science, 1993

Night chilling (5 °C) subsequently lowered photosynthetic intensity in the leaves of maize seedli... more Night chilling (5 °C) subsequently lowered photosynthetic intensity in the leaves of maize seedlings at 20 °C through an increase in leaf diffusive resistance brought on by lower tissue water content in morning hours. A more significant increase in leaf diffusion resistance was observed when soil temperature was lowered than in the case of lower air temperature. The unfavorable effect of soil and air cooling temperature on photosynthesis was limited by air saturated with water vapour. However, as a result of lowering the night temperature from 5 °C to 1 °C, the efficiency of the protective influence of higher atmospheric humidity was decreased. This demonstrates that the participation of factors unrelated to plant water status in inhibiting photosynthesis increases with lower night temperatures. An additional reason for inhibited photosynthesis following cool nights was a decrease in chlorophyll accumulation, below 50 μg per 1 cm2 of leaf area. Zusammenfassung Einflus niedriger Nachttemperaturen auf die Photosyntheseaktivitat von Maissamlingen (Zea mays L.) Nachtkuhle (5 °C) verringerte die Photosyntheseintensitat in den Blattern von Maissamlingen an dem darauffolgenden Tag mit 20 °C als Folge einer Zunahme der Blattdiffusionsresistenz, die sich aus einem geringeren Blattwassergehalt in den Morgenstunden ergab. Eine starkere Zunahme in der Blattdiffusionsresistenz wurde beobachtet, wenn die Bodentemperatur im Vergleich zur niedrigen Lufttemperatur verringert wurde. Der ungunstige Einflus der Boden- und Lufttemperaturen im kuhlen Bereich auf die Photosynthese wurde begrenzt durch mit Wasser gesattigte Luft. Als ein Ergebnis der Verringerung der Nachttemperatur von 5 °C auf 1 °C wurde die Wirksamkeit einer schukzenden Auswirkung hoher Luftfeuchtigkeit verringert. Dies zeigt, das die Wirksamkeit von Faktoren, die bezuglich der Zunahme der Photosynthese nicht in Beziehung zum Wasserstatus der Pflanze stehen, sich mit geringen Nachttemperaturen verstarken. Ein zusatzlicher Grund fur die Einschrankungen der Photosynthese als Folge kuhler Nachte konnte in der Abnahme der Chlorophyllakkumulation unter einen Wert von 50 μg/1 cm2 der Blattflache nachgewiesen werden.

Photosynthetica, 2005

Seedlings of winter rape were cultured in vitro on media containing 24-epibrassinolide, EBR (100 ... more Seedlings of winter rape were cultured in vitro on media containing 24-epibrassinolide, EBR (100 nM) and cadmium (300 µM). After 14 d of growth, fast fluorescence kinetics of chlorophyll (Chl) a and contents of photosynthetic pigments and Cd in cotyledons were measured. Cd was strongly accumulated but its content in cotyledons was 14.7 % smaller in the presence of EBR. Neither Cd nor EBR influenced the contents of Chl a and b and carotenoids. Cd lowered the specific energy fluxes per excited cross section (CS) of cotyledon. The number of active reaction centres (RC) of photosystem 2 (RC/CS) decreased by about 21.0 % and the transport of photosynthetic electrons (ET 0 /CS) by about 17.1 %. Simultaneously, under the influence of Cd, the activity of O 2 evolving centres (OEC) diminished by about 19.5 % and energy dissipation (DI 0 /CS) increased by about 14.6 %. In the cotyledons of seedlings grown on media without Cd, EBR induced only a small increase in the activity of most photochemical reactions per CS. However, EBR strongly affected seedlings cultured with cadmium. Specific energy fluxes TR 0 /CS and ET 0 /CS of the cotyledons of plants Cd+EBR media were about 10.9 and 20.9 % higher, respectively, than values obtained for plants grown with Cd only. EBR also limited the increase of DI 0 /CS induced by Cd and simultaneously protected the complex of OEC against a decrease of activity. Hence EBR reduces the toxic effect of Cd on photochemical processes by diminishing the damage of photochemical RCs and OECs as well as maintaining efficient photosynthetic electron transport.

Journal of Plant Physiology, 2003

Electrical activity (action and variation potentials) and ethylene emission were measured in ther... more Electrical activity (action and variation potentials) and ethylene emission were measured in thermally stimulated Vicia faba minor seedlings. It was determined that variation potential with or without superimposed action potentials was generated and propagated basipetally in response to scorching of the upper leaf. In stimulated plants the level of ethylene production measured in lower, non stimulated leaf was significantly higher than that in the control plants and the difference correlated with the amplitude of the electrical response. Neither variation nor action potential was recorded when ethylene was injected to the chamber covering the experimental leaf. The level of ethylene emission showed clear circadian rhythm when measured at photoperiod 16 : 8 (LD) or at constant light (LL). It is concluded that the sequence of ion fluxes registered as an electrical response of a plant to the thermal stimulus is a signal evoking an enhancement of ethylene emission.

Photosynthetica, 2006

The influence of chilling (8 o C, 5 d) at two photon flux densities [PFD, L = 200 and H = 500 µmo... more The influence of chilling (8 o C, 5 d) at two photon flux densities [PFD, L = 200 and H = 500 µmol(photon) m −2 s −1 ] on the gas exchange and chlorophyll fluorescence was investigated in chilling-tolerant and chilling-sensitive maize hybrids (Zea mays L., K383×K130, K185×K217) and one cultivar of field bean (Vicia faba L. minor, cv. Nadwiślański). The net photosynthetic rate (P N) for the both studied plant species was inhibited at 8 o C. P N of both maize hybrids additionally decreased during chilling. Changes in the quantum efficiency of PS2 electron transport (Φ PS2) as a response to chilling and PFD were similar to P N. Measurements of Φ PS2 /Φ CO2 ratio showed that in field bean seedlings strong alternative photochemical sinks of energy did not appear during chilling. However, the high increment in Φ PS2 /Φ CO2 for maize hybrids can indicate reactions associated with chill damage generation. At 8 o C the non-photochemical quenching (NPQ) increased in all plants with chilling duration and PFD. The appearance of protective (q I,p) and damage (q I,d) components of q I and a decrease in q E (energy dependent quenching) took place. NPQ components of field bean and maize hybrids differed from each other. The amount of protective NPQ (q E + q I,p) components as part of total NPQ was higher in field bean than in maize hybrids at both PFD. On 5 th day of chilling, the sum of q E and q I,p was 26.7 % of NPQ in tolerant maize hybrids and 17.6 % of NPQ in the sensitive one (averages for both PFD). The increased PFD inhibited the ability of all plants to perform protective dissipation of absorbed energy. The understanding of the genotypic variation of NPQ components in maize may have implications for the future selection of plants with a high chilling tolerance.

Journal of Agronomy and Crop Science, 2010

Brassinosteroids are plant steroid hormones important for plant growth and development. They incl... more Brassinosteroids are plant steroid hormones important for plant growth and development. They include more then 70 compounds. Their physiological effect and possibilities of practical use are still being investigated. In this study, we evaluated the effects of exogenously applied 24-epibrassinolide, one of the brassinosteroids, on the grain yield and grain chemical composition (carbohydrates, proteins, fats and minerals) of wheat. Moreover, we analysed the presence of brassinosteroids in newly formed wheat grains after exogenous plant treatment with 24-epibrassinolide. Experiments were performed in a vegetation hall (plants cultivated in pots) and in the field. The tested regulator was applied via 48 h seed soaking (1 mgAEdm)3) or spraying plants at the heading stage (0.25 mgAEdm)3). 24-epibrassinolide increased grain yield in plants growing in the field (by about 20 %), but not in plants cultivated in vegetation hall. Grain chemical composition was altered by 24-epibrassinolide in wheat growing in the vegetation hall; the content of soluble sugars was higher while that of total fats and calcium was lowered, whereas the starch and soluble protein content was not affected. The effect of the hormone was in these cases dependent on the method of its application. As for plants cultivated in the field, the hormone impact on the amount of carbohydrates, proteins, fats and minerals contained in the grains was rather negligible. In wheat grains, the presence of brassinolide, castasterone and 24-epicastasterone was found. 24-Epibrassinolide applied exogenously to plants was not accumulated in newly formed grains. Additionally, significance of ethanol as a hormone solvent is discussed.

Journal of Agronomy and Crop Science, 1995

The relations between the extent of injuries in seedlings caused by a few day-long exposures to c... more The relations between the extent of injuries in seedlings caused by a few day-long exposures to chill (5 o C) and the leakage of K + , Mg 2+ and Ca 2+ ions from the leaves as well as the electric potential in seven maize hybrids, were investigated. The permeability of cells to ions was defined based on their absolute concentration in a water diffusate (C t ) and concentration expressed in relation to the total ion content in the leaves (IL index). At lowered temperature the hybrids of higher resistance to chilling temperature were characterized by a lower value of the IL index for K + and Mg 2+ ions than the chill-sensitive hybrids. On the other hand, absolute concentration of the ions (C t ) Mg 2+ and Ca 2+ leaking from the leaves before chill exposure of the seedlings was positively and highly correlated with the extent of injuries in hybrids caused by 4 day-long exposures to chill. This observation is evidence that the chill injuries were predetermined through increased cell permeability to the mentioned ions at room temperature. Changes in the electric potential of leaves in conditions of lowered temperature preceded the injuries of leaves, which became apparent after a longer period of exposure to chill. Thus, as the leakage of Mg 2+ and Ca 2+ ions occurs, changes in the electric potential may supply early information about the predisposition of the particular maize hybrids to chilling injuries. Leakage measurements of Mg 2+ and Ca 2+ ions from the leaves at room temperature may find application in the selection of chill-tolerant maize genotypes

Journal of Agronomy and Crop Science, 1997

Field beans of indeterminate (cv. Nadwislariski) and determinate (cv. Tibo) growth habits were gr... more Field beans of indeterminate (cv. Nadwislariski) and determinate (cv. Tibo) growth habits were grown on field plots with a density of 20, 40 and 80 plants mat two levels of nitrogen fertilization: low (20 kg N ha~') and very high (150 kg N ha"'). At the phase of intense pod growth the number and the dry matter weight of root nodules as well as their nitrogenase activity and some features of the plants growth were determined, and in the period of ripeness the components of seed yield were established. It was found that increased density of sowing as well as the high level of nitrogen fertilization inhibited the growth and development of root nodules and limited their nitrogenase activity in both cultivars. Plants of both varieties were characterized by a similar potential of forming the root nodules, however, in plants of the cv. Tibo the nitrogenase activity of nodules was much lower than in the cv. Nadwislanski. Increased population density of the plants has in both varieties given increased seed yield when calculated per m-of the soil, compensating in excess the depression of the seed yield from one plant. Such compensation did not occur in the case of the depression of nitrogen fixation under intense nitrogen fertilization.

Journal of Agronomy and Crop Science, 1996

The effect of separate chilling (5 °C for 2 and 4 days) on the shoots and roots of two mai^e hybr... more The effect of separate chilling (5 °C for 2 and 4 days) on the shoots and roots of two mai^e hybrid seedlitigs on the electrsc potential, die composition of fany acids and the ATPase activity in the microsomcs of non-chilled leaves and roots (20 °C) was investigated. It has been found that the low tetnperatuties induced on the non-chilled organs gave similar changes to organs exposed to a reduced temperature. The changes consisted ofa parallel depolarization of leaf and root membranes and simiiarty a decrease in the ATPase activity as well as changes in the unsamratson of the membranes' fatty acids. The reduction of the acid content 18:2 was particularly significant, which in the leaf iJiicrosomes correlated with a drop in the ATPase activity. The similarity between the teactians of the chilled and non-diilled parts of the plant gives evidence of a cominunicaaon' between the organs wWch may facilitate a coordinated reaction of the entire organism to stress. The background for these phenomena couid be the action potential of the chilled parts of seedlings which, in the oon-chilled parts, mig^t produce changes in the structure of biomembranes and in the activity of eniytnes.

Acta Physiologiae Plantarum, 2007

During cold acclimation by higher plants, temperature perception via changes in redox state of Ph... more During cold acclimation by higher plants, temperature perception via changes in redox state of Photosystem II (PSII) and subsequent acclimation of the photosynthetic apparatus to cold is very important for achieving freezing tolerance. These properties were studied in two groups (A and B) of the same backcross 3 (BC 3) progeny derived from a triploid hybrid of Festuca pratensis (2•) • Lolium multiflorum (4•) backcrossed three times onto diploid L. multiflorum cultivars. Leaves of Group A plants formed at 20°C at medium-low light were unable to acclimate their photosynthetic apparatus to cold. Compared to Group B, the Group A plants were also more frost sensitive. This acclimation ability correlated with the freezing tolerance of the plants. However, leaves of the same Group A plants developed at 20°C, but under higher-light conditions had increased ability to acclimate their photosynthetic apparatus to cold. It was concluded that Group A plants may have impaired PSII temperature perception, and this then resulted in their poor capability to cold acclimate.

Australian Journal of Crop Science, Mar 1, 2014

The content of antioxidants (tocopherols, trocotrienols, ascorbic acid, β-carotene) as well as so... more The content of antioxidants (tocopherols, trocotrienols, ascorbic acid, β-carotene) as well as soluble proteins, total fats and soluble sugars were studied in the seeds of pea and lupine after application of brassinosteroid (24-epibrassinolide). Plants were cultured in separate pots in an open vegetation hall in 2010. The following year, a field experiment was carried out in a randomized block design where plants were growing in rows, directly in the soil. 24-Epibrassinolide (0.25-0.5 mg dm-3) was applied via spraying or watering of the flowering plants. Experiments were done during natural vegetation seasons (spring-summer, latitude: 50°03' N, longitude: 19°55' E) and seeds were collected after maturation. In the pea pot experiment, γ-tocopherol content was increased (9%-15%) in seeds after brassinosteroid spraying (0.5 mg dm-3). In the lupine field experiment, αand γ-tocopherol content was elevated in seeds (8%-84%) after brassinosteroid application (0.25 mg dm-3) via both methods. In the pea field and pot experiment, the ascorbic acid content was increased (18-52%) after watering plants with 24-epibrassinolide (0.25 mg dm-3). In lupine seeds, ascorbic acid as well as β-carotene content was elevated after brassinosteroid watering (0.25 mg dm-3). The brassinosteroid effect on the content of proteins, sugars, and fats in seeds was also studied. The results obtained in our study show the possibility of using brassinosteroid to manipulate plant seed content, which may be important from a nutritional point of view. Moreover, the studies reveal some mechanisms of brassinosteroid action on the metabolism of seeds.

Plant Biology, 2013

Festuca arundinacea is a drought tolerant species. Lolium multiflorum has better forage quality b... more Festuca arundinacea is a drought tolerant species. Lolium multiflorum has better forage quality but lower tolerance to abiotic stresses. Their hybrids offer an opportunity to perform research on the molecular basis of tolerance to drought. The aim of this work was to recognise the mechanisms of response to short-term drought (11 days) in a glasshouse in two L. multiflorum/F. arundinacea introgression forms with distinct levels of tolerance to long-term drought (14 weeks) in the field. Measurements of physiological parameters, analyses of protein accumulation profiles using two-dimensional gel electrophoresis, and mass spectrometry identification of proteins, which were accumulated differentially between the selected genotypes during shortterm drought, were performed. Genotype 7/6, with lower yield potential during 14 weeks of drought, and lower ability to re-grow after watering, had a higher capacity for photosynthesis during 11 days of drought. Genotype 4/10, more tolerant to longterm drought, was able to repair damaged cell membranes after watering and was also characterised by lower transpiration during short-term drought. A total of 455 proteins were analysed, and the 17 that were differentially accumulated between the two genotypes were identified. The results of physiological and proteomic research led to a hypothesis that the higher photosynthetic capacity of genotype 7/6 could be due to a more efficient Calvin cycle, supported by higher accumulation of crucial proteins involving chloroplast aldolase.

Journal of Agronomy and Crop Science, 2010

A number of physiological and molecular characteristics are proposed as selection criteria for dr... more A number of physiological and molecular characteristics are proposed as selection criteria for drought tolerance. This study measured the associations between physiological and molecular characteristics of drought response in malting and fodder spring barleys. Plants of 13 malt-and 14 feed-type Polish genotypes were exposed to drought at the four-leaf stage for 7 days. Drought susceptibility indexes (DSI) were calculated for membrane integrity, water status, gas exchange and PSII photochemical activity. Accumulation of HVA1 and SRG6 transcripts in drought was measured with real-time PCR. A wide range of variation in the drought response was observed among studied genotypes. Malting barleys were less sensitive to drought than feed-barleys according to all the traits studied. In both groups, different patterns of relationships between traits were observed. In malting genotypes only, CO 2 assimilation rates in drought, as well as PSII efficiency were related to both water content and the accumulation of HVA1 transcript in leaves. On the other hand the SRG6 expression was highly correlated in both groups of barley with the photochemical efficiency of PSII. The results suggest that different physiological, biochemical and molecular characteristics should be applied in the selection towards drought resistance in the case of malting and fodder barleys.

Acta Physiologiae Plantarum, 2010

The aim of the experiments presented here was twofold. On the one hand, to study the influence of... more The aim of the experiments presented here was twofold. On the one hand, to study the influence of plant growth regulators, i.e. auxins (IAA and NAA), cytokinins (kinetin, zeatin and zeatin riboside), gibberellins: (GA 3) and polyamines (spermidine, spermine and putrescine) on the generative development of winter wheat plants, while on the other to study the interaction of plant growth regulators with electric current in affecting the efficiency of the flowering of wheat plants. Winter wheat var. Grana was subjected to a short vernalization (2 weeks at 5°C ? 10 days at 10°C) on Murashige and Skoog medium containing growth regulators at different concentrations. For Keywords In vitro culture Á Plant growth regulators Á Electric current Á Vernalization Á Winter wheat Communicated by K. Trebacz.

Acta Physiologiae Plantarum, 1998

Murashige & Skoog nutrient was supplemented with subs... more Murashige & Skoog nutrient was supplemented with substances of molecular weight (MW) less than 5 kDa, which were separated from extract of winter wheat ears by means of Sephadex G-25 ultrafiltration. Isolated embryos of the same wheat cultivar (Grana) were vernalized in the nutrient for 0 and 7 days at 2 °C for 2 weeks and planted in a glass-house.

Photosynthetica, 2009

The seeds of soybean cv. Aldana and spring wheat cv. Torka were soaked for 24 h in solution of ze... more The seeds of soybean cv. Aldana and spring wheat cv. Torka were soaked for 24 h in solution of zearalenone [ZEN, 2,4-dihydroxy-6-(10-hydroxy-6-oxo-trans-1-undecenyl)-benzonic acid lactone, 4 mg dm-3 ] and then they were sown in the pot experiment in an open vegetation hall. The after-effects of ZEN on growth of plants, net photosynthetic (P N) and transpiration (E) rates, stomatal conductance (g s), photochemical efficiency of photosystem II (PSII) and on final seeds yield, were determined. A significant increase of seeds yield was revealed in plants of both cultivars i.e. by 22% and 19% of seed (grain) number and by 28 and 24% of seed (grain) mass, in soybean and in wheat, respectively. The photosynthetic rate (P N) was stimulated during the juvenile and final phase by about 13.6% (average) in soybean plants. During other developmental stages, assimilation of CO 2 was retarded. The response of CO 2 assimilation in wheat plants was less pronounced as compared to that in soybean, but an increase of P N by over 24% near the final stage of development was observed. The quantum yield of PSII electron transport (Φ PSII) in soybean plants was changed after the treatment of seeds by ZEN similarly as for the rate of CO 2 , whereas in wheat it continued to gradually increase i.e. during the whole growth period. Changes of Φ PSII both in soybean and in wheat plants, as the response to ZEN treatment, were accompanied with an increase in the efficiency of changes occurring within the antenna (F v '/F m ') as well as within centres of photochemical reactions (q p). The conclusion is that ZEN can affect plant growth and development in many ways, as well as in the status and functioning of the photosynthetical apparatus. Some of the effects can be very longlasting, as e.g. stimulation of production of seed yield in response to treatment of seeds with this substance.

Plant Science, 1997

Damage done to horse bean roots through rapid heating to temperatures above 8O"C, induced the app... more Damage done to horse bean roots through rapid heating to temperatures above 8O"C, induced the appearance of a wave of electric potential which reached the leaves within about 25 s. The passing wave was accompanied by stimulation of the shoot respiration which attained a maximum rate of up to 140-160% of its initial value within 70-80 s after the roots had been heated. Local cooling of the stem (0°C and 2°C) or freezing a section of it with liquid nitrogen, as well as treatment with sodium azide, inhibited the stimulation of respiration, which seems to be a consequence of inhibition and damping of the amplitude of the electric wave reaching the leaves.

Journal of Agronomy and Crop Science, 1993

Night chilling (5 °C) subsequently lowered photosynthetic intensity in the leaves of maize seedli... more Night chilling (5 °C) subsequently lowered photosynthetic intensity in the leaves of maize seedlings at 20 °C through an increase in leaf diffusive resistance brought on by lower tissue water content in morning hours. A more significant increase in leaf diffusion resistance was observed when soil temperature was lowered than in the case of lower air temperature. The unfavorable effect of soil and air cooling temperature on photosynthesis was limited by air saturated with water vapour. However, as a result of lowering the night temperature from 5 °C to 1 °C, the efficiency of the protective influence of higher atmospheric humidity was decreased. This demonstrates that the participation of factors unrelated to plant water status in inhibiting photosynthesis increases with lower night temperatures. An additional reason for inhibited photosynthesis following cool nights was a decrease in chlorophyll accumulation, below 50 μg per 1 cm2 of leaf area. Zusammenfassung Einflus niedriger Nachttemperaturen auf die Photosyntheseaktivitat von Maissamlingen (Zea mays L.) Nachtkuhle (5 °C) verringerte die Photosyntheseintensitat in den Blattern von Maissamlingen an dem darauffolgenden Tag mit 20 °C als Folge einer Zunahme der Blattdiffusionsresistenz, die sich aus einem geringeren Blattwassergehalt in den Morgenstunden ergab. Eine starkere Zunahme in der Blattdiffusionsresistenz wurde beobachtet, wenn die Bodentemperatur im Vergleich zur niedrigen Lufttemperatur verringert wurde. Der ungunstige Einflus der Boden- und Lufttemperaturen im kuhlen Bereich auf die Photosynthese wurde begrenzt durch mit Wasser gesattigte Luft. Als ein Ergebnis der Verringerung der Nachttemperatur von 5 °C auf 1 °C wurde die Wirksamkeit einer schukzenden Auswirkung hoher Luftfeuchtigkeit verringert. Dies zeigt, das die Wirksamkeit von Faktoren, die bezuglich der Zunahme der Photosynthese nicht in Beziehung zum Wasserstatus der Pflanze stehen, sich mit geringen Nachttemperaturen verstarken. Ein zusatzlicher Grund fur die Einschrankungen der Photosynthese als Folge kuhler Nachte konnte in der Abnahme der Chlorophyllakkumulation unter einen Wert von 50 μg/1 cm2 der Blattflache nachgewiesen werden.