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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effect of titanium on assimilation leaf area and chlorophyll content of very early-maturing potato cultivars

100%
Wadas W., Kalinowski K.
Acta Scientiarum Polonorum. Agricultura
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2017
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tom 16
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nr 2
2

Variations of leaf economic spectrum of eight dominant plant species in two successional stages under contrasting nutrient supply

84%
Mao W., Li Y.-L., Zhao X.-Y., Zhang T.-H., Liu X.-P.
Polish Journal of Ecology
|
2016
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tom 64
|
nr 1
Leaf functional traits are indicators of both plant community and ecosystem responses to environmental factors and can thus increase our capacity to understand ecosystem processes and community assembly due to climate change. The variation in leaf functional traits between succession stages in Horqin Sandy Land is caused by soil nutrient content and by intrinsic biological characteristic of species, but the effects are different. Leaf economic spectra were assessed for seven leaf traits of eight species from early and advanced stages of succession. Species from early succession stages are Agriophyllum squarrosum (L.) Moq., Corispermum macrocarpum Bge., Setaria viridis (L.) Beauv. and Pennisetum centrasiaticum Tzvel., and species from advanced successional stages are Chenopodium acuminatum Willd., Chloris virgate Swartz, Digitaria sanguinalis (L.) Scop. and Leymus secalinus (Georgi) Tzvel. All these species were grown in a greenhouse experiment under two contrasting nutrient supplies including high nutrient level (N , with 20 g of nutrient addition) and low nutrient level (N-, with no added nutrients). As expected, the resource uptake strategies of the species were affected by soil fertilization addition. Leaf nitrogen content (LNC), leaf phosphorus content (LPC), and photosynthetic capacity per unit leaf area (Aarea) significantly increased at high nutrient level but LPC is more dramatically changed than others leaf traits. Leaf life span (LLS) and specific leaf area (SLA) did not show similar tendency with succession stage. At the same nutrient level, LES still shows different pattern between the early and the advanced succession stages. Species from early succession stages have higher LPC and Aarea, compared to species from advanced stages. Species from early succession stage also tend to have higher SLA and higher LNC than at the advanced succession stage. The LLS did not show any clear changes with succession process. These results provide evidence that LES shift along the succession process is mainly caused by intrinsic biological characteristic of species.
3

Inter - and intrapopulation variation of leaf morphological traits in natural stands of Buxus hyrcana [Pojark.] in Caspian Forests [Iran]

84%
Yosefzadeh H., Tabari M., Espahbodi K., Jalali G. A., Bussotti F., Abdi E.
Polish Journal of Ecology
|
2009
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tom 57
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nr 2
291-301
The leaf morphology of Buxus hyrcana (Pojark.), shade-tolerant and evergreen species growing in understorey of Caspian Forest was studied in five natural Iranian populations in order to recognize the pattern of within- and among-population variation of selected leaf morphological traits. Fifteen traits were selected and measured or calculated – list in Appendix. Leaves were collected from different geographical (between 36°13′N and 53°15′E) populations of B. hyrcana growing in the Caspian Forests located in Mazandaran Province (northern Iran) in the similar vegetation and site conditions but on different altitudes. Ten mature trees from five relatively small areas (0.5–1 ha) were selected in June. Then ANOVA model was used with both crossed and nested effects. The results showed that variation among the populations was significant in 13 of 15 traits (P <0.05); variation among the trees in the population was significant in 14 of 15 traits (P <0.05). Among all characters measured, the greatest plasticity was found for weight, leaf area mass and specific leaf mass. Function 1 explained 30% of the total variance and Function 2 represented another 17% of the total variance. PCA analysis showed that the most important role in function 1 allocated to width of lamina and leaf figure ratio (length of lamina/width of lamina) and in function 2 to top of leaf figure (width of lamina in 0.1 its length/width of lamina). The results of the average linkage clustering method evidenced four distinct clusters. Generally, morphological traits of leaves of B. hyrcana showed low variation among the considered populations based on clustering analysis, although some trees inside the population showed significantly different values in comparison with other trees.
4

Variation and correlations of leaf traits of two Taxus species with different shade tolerance along the light gradient

84%
Liu W., Li S., Su L., Su J.
Polish Journal of Ecology
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2013
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tom 61
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nr 2
The variations in leaf traits of Taxus species in different light conditions are still poorly understood. We sampled leaves of Taxus yunnanensis W. C. Chang L. K. Fu and Taxus chinensis var. mairei (Lemée and Lév.) W. C. Cheng and L. K. Fu along an illumination gradient (full daylight, 40–60% full daylight, <10% full daylight), and analyzed how seven leaf traits and their correlations changed under different light conditions. The leaf trait that showed the greatest variation was specific leaf area (SLA) for T. yunnanensis, followed by leaf dry mass (LM) for both taxa. The smallest variation was in leaf width (LW) for both taxa. Plasticities of all leaf traits in both taxa were higher than 50%, and those of leaf area (LA), LM and SLA were greater than 80%. The light gradient was positively correlated with leaf length (LL), LM, leaf dry matter content (LDMC), and leaf length to width ratio (LWR). LW and SLA were negatively correlated with the light gradient. Analyses of relationships among leaf traits showed that LM of T. yunnanensis, T. chinensis var. mairei and both taxa was positively correlated with LL, LW, LA, LDMC, and LWR, and negatively correlated with SLA under all light conditions. We concluded that leaf traits and their relationships were affected by light conditions.
5

Light conditions alter accumulation of long chain polyprenols in leaves of trees and shrubs throughout the vegetation season

84%
Bajda A., Chojnacki T., Hertel J., Swiezewska E., Wojcik J., Kaczkowska A., Marczewski A., Bojarczuk T., Karolewski P., Oleksyn J.
Acta Biochimica Polonica
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2005
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tom 52
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nr 1
In many plants belonging to angiosperms and gymnosperms the accumulation in leaves of long chain polyprenols and polyprenyl esters during growth in natural habitats depends on the light intensity. The amount of polyprenols in leaves is also positively correlated with the thickness of the leaf blade (SLA, specific leaf area). The polyprenol content of leaves shows seasonal changes with a maximum in autumn and a minimum in early summer with the difference between poorly and well illuminated plants persisting throughout the vegetation season.
6

Growth analysis using curve fitting method in early and late sown sunflower

84%
Parmar N. G., Chanda S. V.
Plant Breeding and Seed Science
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2002
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tom 46
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nr 1
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Acclimation of acacia hybrid (Acacia mangium x Acacia auriculiformis) vegetative propagules to soil water deficits

67%
Alamgir K. M., Rafiqul Hoque A. T. M., Kamaluddin M.
Dendrobiology
|
2006
|
tom 56
37-43
The aim of the present work was to investigate the acclimation potential of acacia hybrid (Acacia mangium Willd×Acacia auriculiformis A.Cunn.ex Benth)vegetative propagules to soil water stress in the nursery of Institute of Forestry and Environmental Sciences, Chittagong University. Acacia hybrid showed significant decrease in total plant biomass in two months water-stressed conditions. Allocation of assimilates to root growth relative to shoot found to be an important acclimation mechanism. Leaf area ratio (LAR)increased under water-stressed plants with simultaneous increase in specific leaf area (SLA)but almost no change in leaf weight ratio (LWR). Significant increase in LAR with limited water supply by increasing SLA was likely to be an important acclimation potential since this relative increase in leaf area compensated, at least partially, for a lower photosynthesis under water-stressed conditions aswas evident from decreased mean total biomass under water-stressed regimes.
8

Leaf stoichiometric trait and specific leaf area of dominant species in the secondary succession of the Loess Plateau

67%
An H., Shangguan Z.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
Ecological stoichiometry is the study of the balance of multiple chemical elements in ecological interactions. Terrestrial plants exhibit inter- and intra-specific differences in leaf C:N:P stoichiometry that has been used to study plant competition and succession, nutrient use efficiency, N and P nutrient limitation. However, little is known about leaf C:N ratio, N:P ratio in the Loess Plateau, particularly the pattern of leaf C:N:P stoichiometry during the secondary succession. Thus, leaf stoichiometric traits and specific leaf area (SLA) of dominant species at different secondary successional stages in the Loess Plateau were measured. The study was conducted at the Lianjiabian forest region of the Loess Plateau (35.03°–36.37°N and 108.10°–109.08°E), Gansu, China. Leaf C:N:P stoichiometry and specific leaf area of 18 dominant species (herb) community stage (Stipa bungeana Trin, Bothriochloa ischaemun (Linn.) Keng, Carex lanceolata Boott, Artemisia sacrorum Ledeb, Pulsatilla chinensis (Bunge) Regel, Potentilla chinensis Ser), shrub community stage (Sophora viciifolia Hance, Hippophae rhamnoides (Linn.), Ostryopsis davidiana Decne, Rubus palmatus Thunb, Rosa xanthina Lindl, Acer ginnala Maxim, Spiraea pubescens Turcz, Ziziphus jujuba var. spinosa), early forest community stage (Populus davidiana Dode, Betula platyphylla Suk, Platycladus orientalis (Linn.) Franco), climax forest community stage (Quercus liaotungensis Koidz)) at four secondary successional stages were determined in the Loess Plateau in early June of 2006. The herb and shrub community stage had higher SLA than that in the early forest community stage and climax forest community stage. The Leaf C, N, C:N ratio and N:P ratio at different secondary successional stages were significantly different (P <0.05), but the leaf P didn’t differ. The N:P ratio of herb community stage were significant difference from those of the others stages (shrub community stage, early forest community stage and climax forest community stage), but there were not significant difference among the shrub community stage, early forest community stage and climax forest community stage. N:P ratio shifts of the species were consistent along the successional sere, although the N:P ratio of the different species at a successional stage varied considerably. On community level, the lowest N:P ratio (9.8) was found in herb community stage in the secondary succession, the N:P ratio increased to 12.9 in shrub community stage, declined to 12.4 in early forest community stage, and increased in climax forest community stage (e.g. 12.6 in the Quercus liaotungensis Koidz community). The results suggest that the vegetation productivity of the Loess Plateau was N-limited at each secondary successional stage.
9

Influence of soil supplementation with nitrogen and magnesium on the size of assimilation area of maize cultivars (Zea mays L.) differing in genetic profile

67%
Szulc P., Bocianowski J., Rybus-Zajac M.
Electronic Journal of Polish Agricultural Universities. Series Agronomy
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2013
|
tom 16
|
nr 2
10

Leaf-area-specific delivery rates of indole acetic acid and abscisic acid in the transpiration stream of flooded tomato plants in relation to stomatal closure

67%
Janowiak F., Else M. A., Jackson M. B.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2010
|
tom 545
Flooding of the soil induces stomata to close within a few hours decreasing a potential damage of leaves which would otherwise occur because of a decrease of root hydraulic conductivity. The signals triggering these shoot responses have not been fully identified but could include changes in hormone transport from roots to shoots as their synthesis and xylem loading are altered. The present research determined if changes in the delivery of indole acetic acid (IAA) could be a root-born signal comparable with decreases in abscisic acid (ABA) reported previously. Tomato plants at the 7-8-leaf stage were flooded up to 48 h by submerging their pots individually in tap water. Xylem sap was collected from freshly detopped and pneumatically pressurised roots at flow rates equivalent to those of whole-plant transpiration. Concentrations of ABA and IAA in the sap were quantified by the GC-MS and their delivery rates from roots to shoots (fluxes) was calculated an the basis of transpiration rates of the whole plant calculating the amounts delivered per unit area of leaf. Leaf conductance (a measure of stomatal closure) and leaf water potential (LWP) were also measured. Stomata were closed almost completely in 8 h of flooding. This decreased transpiration significantly. Stomatal closure and transpiration remained much below than those of well-drained plants for at least 48 h. Between 4-8 h of flooding, a marked transient decrease in LWP took place which was quickly succeeded by its increase even to values above those of well-drained plants. The concentration and the delivery of ABA from flooded roots to shoots in xylem sap decreased 5- and 7-fold, respectively, within 2 h of flooding and remained lower for at least 48 h, as compared to the control. In contrast, IAA concentrations in xylem sap of flooded plants were above those of well-drained plants. However, slower rates of transpiration generated IAA deliveries that were decreased by 36, 35, 18 and 28% after 2, 4, 6 and 8 h of flooding respectively. The rapid and transient decrease in LWP of leaves and decrease in the delivery of ABA and IAA from roots to shoots during the first hours of flooding were always observed before the stomata started to close. Each is a potentially active signal. While the decrease in ABA is diffucult to explain the stomatal closure, the involvement of the rapidly depressed delivery rates of IAA from roots to shoots during the early flooding merits further investigation.
11

Scaling relationships of leaf traits do not change among months in a temperate shrub species

67%
Du N., Wang R.-Q., Zhang X.-R., Xu F., Tan X.-F., Guo W.-H.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 1
Leaf traits scaling relationships were compared in different months (May, June, July and August) in a temperate shrub species, Vitex negundo Linn. var. heterophylla (Franch.) Rehd. Leaf traits variation and the impact of environment were also studied. Our results showed that specific leaf area (SLA), leaf nitrogen content (Nmass), leaf phosphorus content (Pmass) and leaf chlorophyll content (Chlmass) were positively correlated, and all of the pairwise relationships showed a common standardized major axis (SMA) slope in different months. The variation of SLA, chlorophyll a content (Chlmass a), chlorophyll b content (Chlmass b), Chlmass a/b and maximum quantum yield of PSII (Fv/Fm) were mainly habitat-dependent, while the variation of Pmass and Nmass/Pmass were mainly month-dependent. Redundancy analysis (RDA) was used to further explore the relationships between leaf traits and environmental factors. We found that plants under shade (the relative photosynthetic photon flux density was about 10%) developed light-capturing behavior at leaf level (higher SLA) and cellular level (higher Chlmass/Nmass and lower Chlmass a/b). The increased Nmass/Pmass with month was mainly resulted from the large absorption of soil nitrogen and the decrease of soil pH. In a word, our study indicates that species may not have fundamentally different carbon capture strategies in different months. Variation of different leaf traits are related to different environmental factors in the field.
12

Differential effects of grazing on plant functional traits in the desert grassland

67%
An H., Li G.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 2
Plant functional traits are linked with environmental factors, individuals and ecosystem structure and functions as plants respond and adapt to the environment. Here, the whole-plant traits (plant height and plant biomass), leaf morphological (leaf area, leaf dry mass and specific leaf area) and chemical traits (leaf carbon, nitrogen, phosphorus contents, C/N and N/P ratio) of six dominant species (Cynanchum komarovii Al, Euphorbia esula Linn, Glycyrrhiza uralensis Fisch, Lespedeza potaninii Vass, Agropyron mongolicum Keng and Stipa breviflora Griseb) were studied in the desert grassland of China, with a grazing experiment including four grazing intensity (0.00, 0.45, 1.00, 1.50 sheep ha–1). The effect of grazing on leaf morphological traits were significant for the six dominant species, while the effects on whole-plant traits were highly significant for S. breviflora, A. mongolicum, G. uralensis, L. potaninii and C. komarovii. Three of the six species (S. breviflora, A. mongolicum and L. potaninii) decreased in plant height (PH) with increasing grazing intensity, while specific leaf area (SLA) and leaf N (Nmass) showed the opposite trend. The whole-plant traits were significantly positively correlated with leaf dry mass (LM), but significantly negatively correlated with leaf nitrogen and phosphorus contents. The first principal component analysis (PCA) axis corresponding to plant size (PH and PB) and leaf size (LA and LM), while the second axis of PCA to leaf chemical traits (Nmass, P, C and N/P). Variations of plant traits in response to grazing were mainly explained by size trait and chemical traits. The functional traits cannot be the only basis for predicting plant species in response to grazing, and a functional analysis of the trade-off between plant traits is also needed.
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