Wyniki wyszukiwania

1

Foliar responses of Abie fargesii Franch. to altitude in the Taibai Mts, China

100%

Xu P., Zhang X., Zhao C., Chen L., Gao X., Yao B., Deng J., Deng Y.

Polish Journal of Ecology

|

2014

|

tom 62

|

nr 3

Physiological and ecological adaptations of altitudinal gradients reveal alpine plants’ ecological and evolutionary responses to environmental changes. Here we quantitatively investigated the variation in the foliar physiological and morphological traits of alpine tree species (Abies fargesii) along the altitudinal gradient in the Taibai Mountains, China. We collected the needle samples of Taibai fir (A. fargesii) from seven sites at altitudes of 2550, 2650, 2750, 2850, 2950, 3050 and 3150 m, respectively, and measured the 12 foliar physiological and morphological traits. Each set of needle sample (100 needles) was randomly selected from the upper- third of A. fargesii canopies. The results showed that leaf mass per unit area (LMA), stable carbon isotope composition (δ13C), stomatal rows (SR), leaf carbon concentration per unit area (Carea), leaf nitrogen concentration per unit leaf mass (Nmass) and area (Narea) linearly increase significantly while stomatal density (SD), number of stomata per unit nitrogen concentration (St/N) and per unit leaf mass (St/LM) decrease with the altitudes raise. Moreover, all measured traits presented both strong correlations and significantly linear relationships with the main climate factors such as the mean temperature, rainfall and relative humidity during the growing season as well as the altitudes, except for leaf free water concentration (LWC), leaf carbon concentration per unit leaf mass (Cmass) and C: N ratio. The patterns of foliar traits in response to altitudes imply that the alpine plants need higher cost (e.g. higher nutrient concentration) to adapt to the harsher environments along altitudinal gradient. Moreover, our results show that the variation patterns of the leaf traits for A. fargesii plants should be driven by the interactions of multi-climate factors because the abiotic factors that directly influence the growth of plants covary with the increasing altitudes.

2

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Impact of variable magnetic field stimulation on growth of aboveground parts of potato plants

100%

Marks N., Szecowka P. S.

International Agrophysics

|

2010

|

tom 24

|

nr 2

165-170

3

Nitrogen content and biomass: scaling from the tree to the forest level

100%

Cheng D.-L., Zhong Q.-L.

Polish Journal of Ecology

|

2012

|

tom 60

|

nr 4

Nitrogen is an essential nutrient for plant growth. Although much has been learned about its utilization and distribution within the plant body, little is known about the relationship between nitrogen content and standing biomass at the level of entire forests. Data for nitrogen content (N) and biomass (M) of 10 deciduous species in USA at the individual trees level and 37 species grown in three forest biomes (i.e. tropic, subtropics, and temperate) in China at stands level were gathered to determine the N versus M scaling relationships for different tissue- and organ-types (e.g. bark and leaves). Model Type II regression protocols were used to calculate scaling exponents and allometric constants (i.e. slopes and y-intercepts of log-log bivariate plots, respectively) between N and M to. At the level of individual plants, N scaled nearly isometrically with M for the different tissue- and organ-types (i.e. Nα M 0.97–1.04). At the stand-level, N scaled similarly with respect to leaf, branch, and bark M, despite differences in stand size-frequency distributions and species composition. However, total stand N scaled allometrically with respect to total stem or root M and thus to total stand mass (i.e. N α MT 0.77–0.87). This was attributed to the accumulation of wood (and other ‘necromass’ tissue components that have lower N content than physiologically active tissues) in progressively older (and thus more massive) tree stands. When coupled to the scaling of N with respect to annual plant growth rates, these exponents provide important boundary conditions with which to model forest nutrient cycling.

4

Using the conservative nature of fresh leaf surface density to measure foliar area

100%

Castillo O. S., Zaragoza E. M., Alvarado C. J., Barrera M. G., Dasgupta-Schubert N.

International Agrophysics

|

2014

|

tom 28

|

nr 4

For a herbaceous species, the inverse of the fresh leaf surface density, the Hughes constant, is nearly conserved. We apply the Hughes constant to develop an absolute method of leafarea measurement that requires no regression fits, prior calibrations or oven-drying. The Hughes constant was determined in situ using a known geometry and weights of a sub-set obtained from the fresh leaves whose areas are desired. Subsequently, the leaf-areas (at any desired stratification level), were derived by utilizing the Hughes constant and the masses of the fresh leaves. The proof of concept was established for leaf-discs of the plants Mandevilla splendens and Spathiphyllum wallisii. The conservativeness of the Hughes constant over individual leaf-zones and different leaftypes from the leaves of each species was quantitatively validated. Using the globally averaged Hughes constant for each species, the leaf-area of these and additional co-species plants, were obtained. The leaf-area-measurement-by-mass was cross-checked with standard digital image analysis. There were no statistically significant differences between the leaf-area-measurement-by-mass and the digital image analysis measured leaf-areas and the linear correlation between the two methods was very good. Leaf-areameasurement- by-mass was found to be rapid and simple with accuracies comparable to the digital image analysis method. The greatly reduced cost of leaf-area-measurement-by-mass could be beneficial for small agri-businesses in developing countries.

5

The use of top cross mating system in the study of general combining ability and heritability in strawberry (Fragaria × ananassa Duch.)

80%

Gawronski J.

Electronic Journal of Polish Agricultural Universities. Series: Horticulture

|

2014

|

tom 17

|

nr 4

6

The age-related changes of leaf structure and biochemistry in juvenile and mature subalpine fir trees (Abies faxoniana Rehder and E.H. Wilson.) along an altitudinal gradient

80%

Peng G., Wu C., Xu X., Yang D.

Polish Journal of Ecology

|

2012

|

tom 60

|

nr 2

In woody perennials, leaf structure and biochemistry vary with tree age under changing environments. However, the related eco-physiological mechanisms have not been elucidated yet. In this study, we investigated agerelated responses of juvenile and mature subalpine fir trees (Abies faxoniana Rehder & E.H. Wilson.) growing at altitudes between 2,500 and 3,500 m in the Wanglang Natural Reserve in southwest China, to study the adaptive strategies of different age trees to suit changing environments. We found that there were distinct age- and altituderelated changes in the structural and biochemical characteristics of leaves. At all altitudes, mature trees exhibited higher area- and mass-based leaf nitrogen content (Narea, Nmass), leaf mass per area (LMA) and stable isotope carbon composition (δ13C), and a lower chlorophyll (Chl) content than those juvenile trees, except for Nmass at 3,000 m as well as LMA at 2,750 m, where the values of Nmass and LMA in mature trees were slightly lower than those in juvenile trees. Furthermore, leaf characteristics showed significant differences in the change rates with altitude between different age groups. Our results indicated that assimilative organs in mature trees do not suffering from nutrient deficiency and that juvenile and mature trees possess different adaptive growth strategies under changing environments, as indicated by higher leaf N content in mature trees and the opposite patterns of LMA and Chl content between two age groups. We also concluded that juvenile could be more sensitive to global warming due to a greater altitudinal influence on the leaf traits in juvenile trees than those in mature trees.

7

Contents of chlorophyll and selected mineral components and the yield of common thyme [Thymus vulgaris L.] at differentiated nitrogen fertilization

80%

Golcz A., Politycka B.

Herba Polonica

|

2009

|

tom 55

|

nr 3

69-75

The vegetation experiment was carried out in pots, in an unheated greenhouse of Experimental Station ‘Marcelin’, Poznań University of Life Sciences. The studies were carried out on the effect of nitrogen nutrition on the herb fresh matter and on its dry crumbled matter as well as on the contents of chlorophyll a and b, nitrogen, magnesium and iron in leaves of common thyme of ‘Słoneczko’ cultivar. Nitrogen was applied in the form of NH4 NO3 before vegetation (control – without nitrogen addition, 60, 120, 180 and 240 mg N dm-3 substrate) and as a top dressing with an addition of 60 mg N dm-3 in all variants with nitrogen fertilization. Herb harvest was carried out twice. It was found that nitrogen, irrespective of its dose, significantly decreased the level of chlorophyll a and b (on the average by 60%) and the iron content (on the average by 40%). The decreased chlorophyll level in thyme leaves with nitrogen application was positively correlated with iron content. No dependence was found between the level of chlorophyll and the nitrogen content in the herb. Nitrogen fertilization significantly increased both the yield of herb fresh matter and of the dry raw material. In case of dry raw material, no differences were found in the yield depending on the differentiated nitrogen nutrition

8

Nutrient content in leaves from different strata of a swamp forest from Northern Turkey

80%

Kutbay H. G.

Polish Journal of Ecology

|

2001

|

tom 49

|

nr 3

9

The effect of placement and light conditions during foliar application of Insol U fertilizer on gas exchange, yield and quality of spinach (Spinacia oleracea L.)

71%

Borowski E., Michalek S.

Folia Horticulturae

|

2009

|

tom 21

|

nr 1

61-71

10

Stopien rozwoju siewek burakow cukrowych w okresie mlodocianym, powierzchnia zyciowa a koncowa masa korzeni i lisci

61%

Wyszynski Z.

Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin

|

1997

|

nr 202

63-67

11

Wartosc wskaznikow charakteryzujacych stan fizjologiczny bulw i rozwoj rosliny ziemniaka. Cz. V. Rozwoj czesci nadziemnej

41%

Zarzynska K.

Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin

|

2001

|

tom 217

151-168

Ograniczanie wyników

Foliar responses of Abie fargesii Franch. to altitude in the Taibai Mts, China

Impact of variable magnetic field stimulation on growth of aboveground parts of potato plants

Nitrogen content and biomass: scaling from the tree to the forest level

Using the conservative nature of fresh leaf surface density to measure foliar area

The use of top cross mating system in the study of general combining ability and heritability in strawberry (Fragaria × ananassa Duch.)

The age-related changes of leaf structure and biochemistry in juvenile and mature subalpine fir trees (Abies faxoniana Rehder and E.H. Wilson.) along an altitudinal gradient

Contents of chlorophyll and selected mineral components and the yield of common thyme [Thymus vulgaris L.] at differentiated nitrogen fertilization

Nutrient content in leaves from different strata of a swamp forest from Northern Turkey

The effect of placement and light conditions during foliar application of Insol U fertilizer on gas exchange, yield and quality of spinach (Spinacia oleracea L.)

Stopien rozwoju siewek burakow cukrowych w okresie mlodocianym, powierzchnia zyciowa a koncowa masa korzeni i lisci

Wartosc wskaznikow charakteryzujacych stan fizjologiczny bulw i rozwoj rosliny ziemniaka. Cz. V. Rozwoj czesci nadziemnej