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Monitoring of xylem formation in Picea abies under drought stress influence

100%

Gryc V., Hacura J., Vavrcik H., Urban J., Gebauer R.

Dendrobiology

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2012

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tom 67

The effect of drought stress on regular cambium activity and wood formation in stems of two different clones of Norway spruce (Picea abies (L.) Karst.) was investigated. Tissue samples were taken during the growing season from May to September 2010. Artificial drought stress, induced by long-term sheltering of the soil, was significantly manifested in clone 15. In the stressed individual, the period of cambium activity was shorter, the total number of formed cells was lower and the resulting tree ring was narrower. The number of cells in the phases of postcambial growth and secondary cell wall formation was significantly lower in comparison to the control tree. The tracheid lignification process was slower in the tree stressed by water deficit and the first mature tracheids were observed later. On the other hand, in clone 18 probably genetic dispositions played an important role as no considerable deviations in the cambium activity and new wood cells production were observed. Fitting xylem increments to the Gompertz function showed that the period of the most intensive cell formation was at the turn of June and July and the maximum daily production of new cells was higher in non-stressed individuals than in the stressed ones. The results of the experiment lead us to the conclusion that drought stress can significantly affect the cambium activity of some clones, the differentiation process of anatomical elements, and thus also the resulting tree ring width.

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Evaluation of allelopathic potential of safflower genotypes (Carthamus tinctorius L.)

86%

Motamedi M., Karimmojeni H., Sini F. G.

Journal of Plant Protection Research

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2016

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tom 56

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nr 4

Forty safflower genotypes were grown under normal irrigation and drought stress. In the first experiment, the allelopathic potential of shoot residues was evaluated using the sandwich method. Each genotype residue (0.4 g) was placed in a sterile Petri dish and two layers of agar were poured on that. Radish seeds were placed on agar medium. The radish seeds were cultivated without safflower residues as the controls. The length of the radicle, hypocotyl, and fresh biomass weight and seed germination percentages were measured. A pot experiment was also done on two genotypes with the highest and two with the lowest allelopathic activity selected after screening genotypes in the first experiment. Before entering the reproductive phase, irrigation treatments (normal irrigation and drought stress) were applied. Shoots were harvested, dried, milled and mixed with the topsoil of new pots and then radish seeds were sown. The pots with safflower genotypes were used to evaluate the effect of root residue allelopathy. The shoot length, fresh biomass weight, and germination percentage were measured. Different safflower genotypes showed varied allelopathic potential. The results of the first experiment showed that Egypt and Iran-Khorasan genotypes caused maximum inhibitory responses and Australia and Iran-Kerman genotypes resulted in minimum inhibitory responses on radish seedling growth. Fresh biomass weight had the most sensitivity to safflower residues. The results of the pot experiment were consistent with the results of in vitro experiments. Residues produced under drought stress had more inhibitory effects on the measured traits. Safflower root residue may have a higher level of allelochemicals or different allelochemicals than shoot residue.

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The effect of drought stress on wettability of barley leaf surface

86%

Lukowska M.

Acta Agrophysica

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2015

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tom 22

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nr 3

The aim of the study was to determine the changes of plant surface wettability caused by environmental drought stress. Two Polish cultivars of spring barley (Hordeum vulgare) Poldek and Stratus were tested. The low soil moisture was stabilised at pF 3.5 while the control soil moisture at pF 2.2. The wettability was determined by water contact angle. The measurements were performed on fresh leaves before and after washing in chloroform. Generally, drought led to hydrophobisation of the surface of plant leaves. The use of chloroform caused greater changes in contact angle values for stressed than for control plants, but this reaction was variety-specific and leaf-age dependent.

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Differences in response to drought stress between triticale and maize plants expressed by the leaf gas exchange and spectrofluorimetric methods

86%

Hura T., Grzesiak M. T., Hura K., Grzesiak S., Rzepka A.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

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Grain yield and yield components of spring barley genotypes as the indicators of their tolerance to temporal drought stress

86%

Pecio A., Wach D.

Polish Journal of Agronomy

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2015

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nr 21

In 2011 year research project on breeding spring barley genotypes tolerant to temporary drought stresses has started. The authors’ responsibility was to test the productivity of genotypes derived from different parental forms obtained in scope of the project for a drought tolerance in pot experiment. In the years 2011–2013 three consequtive series of experiments with approximately seventy genotypes each year have been carried on. Two reference Polish varieties were included into each set. At the control treatment, plants were grown at the optimal soil moisture level of 13–15% weight by weight for the whole vegetation period. Drought stresses were introduced at the tillering stage (BBCH 23) for the period of 11 days or at full fl ag leaf stage (BBCH 45-47) for the period of 14 days. At the both stress treatments, the moisture was maintained at the level of 5–6% weight by weight. Plants were harvested at full maturity stage and the grain and straw yields, and yield components i.e. number of productive tillers, number of grains per spike and weight of 1000 grains were determined. Spring barley showed a higher tolerance to the drought stress at tillering stage than at fl ag leaf stage. Barley genotypes differed in their response to temporary drought stresses due to diverse ability for regenerating after the stress removal. The tolerance of the genotypes to drought stress imposed at tillering stage resulted from their ability to produce additional fertile tillers. The tolerance of the studied spring barley genotypes to temporal drought stress at fl ag leaf stage can be explained by compensation of the reduced grain number per spike through increasing the weight of 1000 grains.

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Effect of combined drought and heat stress on heat shock proteins in wheat varieties

86%

Grigorova B., Vasseva I., Demirevska K., Feller U.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

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Protective role of Asahi SL against drought stress

86%

Przybysz A., Janowiak F., Slowinski A., Gawronska H.

Zeszyty Problemowe Postępów Nauk Rolniczych

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2010

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tom 545

It is a common opinion that main challenge for plant production is to cope with environmental stresses, both abiotic and biotic. Although biostimulator Asahi SL has been used for years to improve plant status and obtain possibly the highest and best quality yield, especially under conditions unfavourable for plant cultivation, its mode of action is still not understood. In this work the effect of Asahi SL on Arabidopsis thaliana plants grown under drought stress was studied. Plants grown under drought stress conditions and treated with Asahi SL were, as compared to untreated, higher and more advanced in development, particularly generative. Biomass accumulation was stimulated by biostimulator mainly due to better photosynthetic apparatus efficiency manifested by a higher (i) assimilation area, (ii) chlorophyll content, (iii) intensity of photosynthesis and (iv) improvement of chlorophyll a fluorescence parameters. Asahi SL treated plants were characterized by a lower concentration of biological active ABA. Despite the higher transpiration and lowered stomatal resistance RWC and water content were unchanged in Asahi SL treated plants which can be explained by increased water uptake in biostimulator sprayed plants. The obtained results clearly showed that the application of biostimulator played a protective role against drought stress.

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The application of spectrofluorimetric methods for studying the different responses soil drought in triticale and maize plants

86%

Hura T., Hura K., Grzesiak M. T.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

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DNA methylation dynamics under drought stress in barley

86%

Chwialkowska K., Szarejko I., Kwasniewski M.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 3

10

Elevated CO2 mitigates the impact of a combination of heat wave and drought in Arabidopsis thaliana

86%

Zinta G., AbdElgawad H., Domagalska M., Vergauwen L., Nijs I., Beemster G., Asard H., Janssens I.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 2

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The response of winter wheat plants treatmented with hyaluronic acid to drought stress

86%

Mykhalskyi M. F.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

12

Effect of biostimulants on chlorophyll fluorescence parameters of broccoli (Brassica oleracea var. italica) under drought stress and rewatering

86%

Kaluzewicz A., Baczek-Kwinta, Krzesinski W., Spizewski T., Zaworska A.

Acta Scientiarum Polonorum. Hortorum Cultus

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2018

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tom 17

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nr 1

The aim of the research was to determine the influence of biostimulants amino acids and amino acids + Ascophyllum nodosum filtrate on two broccoli cultivars ‘Agassi’ and ‘Tiburon’ and their response to soil drought. The plants were watered with Ascophyllum nodosum filtrate before planting and sprayed with amino acids after planting three times. Chlorophyll fluorescence measurements were performed before, during and after stress. They showed a considerable difference in cultivars’ response to stress, with ‘Agassi’ being more sensitive. Application of biostimulants enhanced the tolerance to drought stress. Maximum photochemical efficiency of PSII was unchanged, whereas the quantum yield of electron transport and photochemical fluorescence quenching values increased and the non-photochemical fluorescence quenching decreased. Moreover, the apparent photosynthetic electron transport rate rose. Chlorophyll content index was affected by the cultivar and application of biostimulants.

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Effect of zearalenone on yield of soybean

86%

Dziurka M., Biesaga-Koscielniak J., Janeczko A., Adamska A., Filek M., Koscielniak J., Szarek-Lukaszewska G., Janeczko Z.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

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Calcium channels and membrane disorders induced by drought stress in Vicia faba plants supplemented with calcium

86%

Abdel-Basset R.

Acta Physiologiae Plantarum

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1998

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tom 20

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nr 2

Vicia faba plants were grown under drought conditions and variously supplemented with calcium. Drought stress markedly inhibited the growth of Vicia faba plants. Ca²⁺ ameliorated to a large extent this inhibition; fresh weight, dry mass, chlorophyll and water contents were variably improved. Membranes were, also, negatively affected by drought stress and percentage leakage was elevated. Concomitantly, the efflux of K⁺ and Ca²⁺ was enhanced by drought but lowered by supplemental Ca²⁺. In addition, membranes of droughted plants were sensitive to the Ca²⁺ channel blockers lanthanum, nifedipine or verapamil more than those of control plants. These blockers significantly increased the efflux of K⁺ and Ca²⁺ as well as percentage leakage particularly in those of droughted plants. The above results indicated that the functioning of the calcium channels was negatively affected when Vicia faba was grown under drought conditions. However, much of the drought-induced disorders including sensitivity towards the applied calcium channel blockers could be ameliorated by supplemental Ca²⁺.

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Invariant allometric relationship between above- and below-ground biomass along a moisture gradient in North - West China

72%

Cheng D. L., Wang G.-X., Tang Q.-L., Li T., Zhong Q.-L.

Polish Journal of Ecology

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2009

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tom 57

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nr 4

669-675

Biomass allocation pattern is an important plant characteristic which influences how plants respond to abiotic and biotic heterogeneity. Prior studies indicate that above-ground biomass scales nearly isometrically with respect to below-ground biomass regardless of environment or phyletic affinity. However, such rule has been mostly tested with data on trees and usually without drought stress. Given the importance of this predicted relationship, it should be evaluated for a wider range of species and environmental conditions. Variations of the above- and belowground biomass (MA and MR, respectively) were determined from five sites in north-west China, which compose a natural moisture gradient (aridity index ranging from 0.95 to 1.98). Model Type II regression protocols were used to compare the numerical values of MA vs MR scaling exponents (i.e. slopes of log-log linear relationships). The resulting five scaling exponents were indistinguishable and had a similar, nearly isometric slope (i.e. MA ∞ MR ͌ ¹‧⁰). Significant variation was observed in the Y-intercepts of the five regression curves, because of the absolute differences in MA or MR. These results support prior allometric theory, which reveals an isometric relationship between above- and below-ground biomass, and may provide a suitable method to estimate the regional below-ground biomass based on the direct aboveground measurements.

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