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1

Habitat effects on leaf morphological plasticity in Quercus acutissima

100%
Xu F., Guo W., Xu W., Wang R.
Acta Biologica Cracoviensia. Series Botanica
|
2008
|
tom 50
|
nr 2
19-26
Phenotypic plasticity acts to increase the performance of plants under stress. Leaf morphological plasticity and its causes in different environments are incompletely understood. We measured the leaf morphological parameters of Quercus acutissima Carr. seedlings, including leaf size, leaf shape and venation pattern, assessing the effects of different habitat conditions on leaf morphological plasticity. A field study in forest edge and understory was combined with experiments simulating different light and water conditions. Leaf morphology variations occurred over most of the parameters, and the causes were consistent between the field study and lab experiment. Leaf size decreased with low supply of light and water. Leaf length and width were only affected by leaf area. The leaf petiole did not lengthen under shade stress, suggesting a trade-off relationship between functional tissues and support structures. Leaf shape became narrower in drought and broader in the shade, as reflected in changes in three leaf fractions. Higher vein density played a part in enhancement of mechanical support and water supply. Leaves with more teeth show more active photosynthesis, but are disadvantageous in xeric environments because of higher transpiration. Light was the main factor inducing leaf morphological plasticity. The variations caused by drought were due mainly to the allometry. Our results showed that the leaves of Q. acutissima seedlings respond to different habitats with phenotypic plasticity of morphology, suggesting that this is an important mechanism for seedlings to adapt to broader ecological amplitudes.
2

Production and molecular characterization of two new Citrus somatic hybrids for scion improvement

100%
Cai X., Duan Y., Fu J., Guo W.
Acta Physiologiae Plantarum
|
2010
|
tom 32
|
nr 1
Somatic hybridization by protoplast fusion from cell suspension cultures and leaf parent has been a well-established technique holding great potential for citrus variety improvement. In this study, somatic hybrid plants were regenerated from the following two fusion combinations: ‘Murcott’ tangor (Citrus reticulata Blanco × C. sinensis (L.) Osbeck) + Hirado Buntan Pink pummelo (HBP) (C. grandis (L.) Osbeck) and ‘Bingtang’ orange (C. sinensis (L.) Osbeck) + Calamondin (C. microcarpa Bunge). Somatic hybrids were selected at an early stage based on their higher capacity for embryogenesis comparing to non-hybrid cells. Flow cytometry analysis showed that all plants from pre-selected lines of the two combinations were tetraploid. SSR analysis confirmed their hybrid nature, with nuclear DNA from both fusion parents, and absence of parental specific bands was also detected. Cytoplasmic compositions of the recovered plants were further revealed by CAPS and cpSSR analysis. The allotetraploid somatic hybrids from the ‘Murcott’ tangor + HBP combination will be applied to develop triploid seedless cultivars by interploid crossing with diploid seedy citrus cultivars, and those from ‘Bingtang’ orange + Calamondin could be valuable for Asiatic citrus canker-tolerant and ornamental citrus breeding.
3

Morphological and physiological responses of Vitex negundo L. var. heterophylla (Franch.) Rehd. to drought stress

100%
Du N., Guo W., Zhang X., Wang R.
Acta Physiologiae Plantarum
|
2010
|
tom 32
|
nr 5
Water is a main factor limiting plant growth. Integrative responses of leaf traits and whole plant growth to drought will provide implications to vegetation restoration. This study investigated the drought responses of Vitex negundo L. var. heterophylla (Franch.) Rehd. with a focus on leaf morphology and physiology, seedling growth and biomass partitioning. Potted 1-year-old seedlings were subjected to four water supply regimes [75, 55, 35 and 15% field capacity (FC)], served as control, mild water stress, moderate water stress and severe water stress. Leaf morphological traits varied to reduce the distance of water transfer under water stress and leaflets were dispersed with drought. Net photosynthetic rate decreased significantly under water stress: stomatal closure was the dominant limitation at mild and moderate drought, while metabolic impairment was dominant at severe drought. The physiological impairment at severe drought could also be detected from the relative lower water use efficiency and nonphotochemical quenching to moderate water stress. Total biomass of well-watered plants was more than twice that at moderate water deficit and nearly ten times that at severe water deficit. In summary, V. negundo var. heterophylla had adaptation mechanism to water deficit even in the most serious condition, but different strategies were adopted. Seedlings invested more photosynthate to roots at mild and moderate drought while more photosynthate to leaves at severe drought. A nearly stagnant seedling growth and a sharp decline of total biomass were the survival strategy at severe water stress, which was not favorable to vegetation restoration. Water supply above 15% FC is recommended for the seedlings to vegetation restoration.
4
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Content available

Hierarchy of plasticity traits in responses of Quercus aliena to light conditions and water availability

88%
Xu N., Wang R., Liu J., Lu P., Guo W.
Dendrobiology
|
2015
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tom 74
This study aimed to investigate plasticity of different plant traits to varied light and water availability. A greenhouse experiment was conducted with Quercus aliena seedlings with two light and four soil water levels. Plant traits related to leaf physiology, morphology, anatomy, and biomass production were determined. The results showed that plant size had significant effects on leaf area, leaf number, shoot height, basal diameter and crown area. After excluding the influence of plant size, water treatment had stronger effects on plants compared to light levels, and their interaction effect was significant. The limited water supply significantly inhibited leaf photosynthetic rate and the fluorescence efficiency under high light. However, leaves submitted to moderate drought stress showed enhanced fluorescence activity under shade condition. Grand plasticity of leaf physiology and growth was the highest, followed by biomass allocation and leaf morphology, and lastly anatomy, and this ranking did not change as resources considered. Among the variables, leaf petiole length, chlorophyll content and leaf area could be selected as candidates for estimation of species’ plasticity to water, light and their interaction, respectively. Therefore, our results suggested that there was a hierarchy existing among traits plasticity in Q. aliena, and supported the aboveground facilitation hypothesis that shade could alleviate the adverse effect of drought.
5

Increased nitrogen deposition alleviated the adverse effects of drought stress on Quercus variabilis and Quercus mongolica seedlings

88%
Xu N., Guo W., Liu J., Du N., Wang R.
Acta Physiologiae Plantarum
|
2015
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tom 37
|
nr 06
The plasticity response of Quercus variabilis and Quercus mongolica seedlings to combined nitrogen (N) deposition and drought stress was evaluated, and their performance in natural niche overlaps was predicted. Seedlings in a greenhouse were exposed to four N deposition levels (0, 4, 8, and 20 g N m-2 year-1) and two water levels (80 and 50 % field-water capacity). Plant traits associated with growth, biomass production, leaf physiology, and morphology were determined. Results showed that drought stress inhibited seedling performance, altered leaf morphology, and decreased fluorescence parameters in both species. By contrast increased N supply had beneficial effects on the nutritional status and activity of the PSII complex. The two species showed similar responses to drought stress. Contrary to the effects in Q. mongolica, N deposition promoted leaf N concentration, PSII activity, leaf chlorophyll contents, and final growth of Q. variabilis under well-watered conditions. Thus, Q. variabilis was more sensitive to N deposition than Q. mongolica. However, excessive N supply (20 g N m-2 year-1) did not exert any positive effects on the two species. Among the observed plasticity of the plant traits, plant growth was the most plastic, and leaf morphology was the least plastic. Therefore, drought stress played a primary role at the whole-plant level, but N supply significantly alleviated the adverse effects of drought stress on plant physiology. A critical N deposition load around 20 g N m-2 year-1 may exist for oak seedlings, which may more adversely affect Q. variabilis than Q. mongolica.
6

miR-3188 Regulates proliferation and apoptosis of granulosa cells by targeting KCNA5 in the polycystic ovary syndrome

88%
Zhou S., Xia L., Chen Y., Guo W., Hu J.
Acta Biochimica Polonica
|
2021
|
tom 68
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nr 1
7

Morphological and biomass characteristic acclimation of trident maple (Acer buergerianum Miq.) in response to light and water stress

76%
Guo X., Guo W., Luo Y., Tan X., Du N., Wang R.
Acta Physiologiae Plantarum
|
2013
|
tom 35
|
nr 04
Acer buergerianum Miq. (Trident maple) is a native species of China with a large distribution, but exist in small population. Water and light are two important factors limiting plant growth and are crucial in the framework of forest regeneration. However, there is no consensus on how shade interacts with drought. Four hypotheses in the recent literature variously predict that shade will have a stronger, weaker or equal impact on seedlings under drought stress. This study investigated the interactive responses of A. buergerianum to light and water focusing on seedling growth, leaf morphology and biomass partitioning by performing a growth experiment in pots with different water supply regimes [15, 35, 55, 75, 95 % of field capacity (FC)] combined with two light regimes (10 and 66 % of full sunlight). After 123 days treatment, the results showed that shade greatly reduced growth and biomass, in contrast enhancing the amount of chlorophyll, the amount of water in the leaves, and the specific leaf area. Drought reduced growth, biomass, and the bulk of the leaves. Most leaf traits and biomass characteristics had strong interactions in their responses to light and water treatments. Allometric analysis revealed that water and light had no effects on root to shoot ratios, main root to lateral root ratios, and root mass ratios. Shade alleviated the negative impact of drought. A. buergerianum successfully adapted to the various light and water conditions. We recommend a water supply above 15 % FC to keep the seedlings vigorous, under both sunlight conditions.
8

RNA-sequencing analysis reveals transcriptional changes in the roots of low-cadmium-accumulating winter wheat under cadmium stress

76%
Xiao Y., Du Z., Qi X., Wu H., Guo W., Zhao Z.
Acta Physiologiae Plantarum
|
2019
|
tom 41
|
nr 01
9

Leaf movement and photosynthetic plasticity of black lokust (Robinia pseudoacacia) alleviate stress under different light and water conditions

76%
Xu F., Guo W., Wang R., Xu W., Du N., Wang Y.
Acta Physiologiae Plantarum
|
2009
|
tom 31
|
nr 3
Leaf morphological, physiological and biochemical characteristics of Robinia pseudoacacia L. seedlings were studied under different stress conditions. The plants were subjected to drought and shade stress for one month. Leaf inclination, chlorophyll fluorescence and chlorophyll content were measured at the first day (shortterm stress) and at the end of the stress period (long-term stress) and in the recovery period. Leaf inclination was affected mainly by light; a low level of irradiance caused leaves to be arranged horizontally. Diurnal rhythmicity was lost after the long-term stress, but resumed, in part, in the recovery period. Drought stress caused leaves to tilt more obviously and decreased damage to the photosystem. Sun avoiding movement in a single leaf and sun tracking movement in the whole plant coexisted. Significant physiological changes occurred under different conditions of light. Increased energy dissipation and light capture were the main responses to high and low level of irradiance, respectively, and these were reflected by changes of chlorophyll fluorescence and chlorophyll content. Phenotypic plasticity in the leaflet enhanced the protective response to stress. These adaptive mechanisms may explain better survival of R. pseudoacacia seedlings in the understory, especially during the drought periods, and made it to be the preponderant reforestation species in Shandong Province of China.
10

The response of wetland plant communities to disturbance: alleviation through symmetric disturbance and facilitation

76%
Xu F., Li M., Zhou D., Liu X., Wang R., Guo W.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 3
The study pays attention to disturbances in early successional communities of wetland vegetation. We conducted artificial disturbances in a community of Suaeda salsa and Phragmites australis in the Yellow River Delta (China). Eight types of disturbances combining mowing treatments with species treatments were applied. Removal of the standing litters of P. australis or not was defined as mowing treatments, and removal of two species solo or both was defined as species treatments. We sampled 80 quadrats from the treatments plots at different intervals after the disturbance to investigate plant height, abundance, aboveground biomass, the distance between plants to reflect the effect of disturbance on composition, structure, productivity, and function of the plant communities. The strategies of seedling emergence and height growth differed as the canopy changed. Biomass contribution of different species, combined with disturbance intensity, was the main factors that affected the productivity. Homogeneity of disturbance was better for maintaining the functions of plant community in compared with the competitiveness (C), stress-tolerance (S) and ruderality (C-S-R) signatures with the control. Facilitations were reflected by the stagger arrangements in relative growth rates of the two species and in plant-plant interactions calculated by a modified function of competition. Adapting to symmetric disturbance and developing facilitative interactions are important requirements for early succession terrestrial vegetation to establish and stabilize in the seriously saline environments of wetlands.
11

Application analysis of the ecological value of agricultural lands in the upper Yongding River Basin

76%
Zang W., Fu Y., Zhang J., Shi W., Qian Z., Guo W., Liu L.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 2
The value of agro-ecosystem services is closely related to crop yield. As a production input component in an agro-ecosystem, agro-ecosystem services have practical value. It is generally believed that agro-ecosystem services are substitutes for purchase investment and can decrease agricultural production costs. Crop yield increases may negatively affect agro-ecosystem protection, and conversely, agro-ecosystem protection may result in crop yield reductions. Based on the established production model of agro-ecosystems, we determined the reasonable substitutive conditions and production outputs, and we quantitatively studied the ratio of the land area for agricultural production to that for ecosystem services. With the upper Yongding River Basin in China as the study area, we calculated agricultural yield elasticity and concluded that the corresponding crop yield would be reduced by 2.7% when the land area for ecosystem services in the basin increased by 1.0%. At present, the ecological service value of the Yongding River Basin showed an increasing trend.
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effects of nitrogen addition on growth and photosynthetic characteristics of Acer truncatum seedlings

64%
Guo X., Wang R., Chang R., Liang X., Wang C., Luo Y., Yuan Y., Guo W.
Dendrobiology
|
2014
|
tom 72
Increasing levels of atmospheric nitrogen deposition have greatly affected forest trees. Acer truncatum Bunge has a large distribution in northern China, Korea and Japan and plays an important ecological role in forest ecosystems. We investigated the responses of A. truncatum to a broad range of nitrogen addition regimes with a focus on seedling growth, biomass partitioning, leaf morphology, gas exchange physiology and chlorophyll fluorescence physiology. Moderate nitrogen addition promoted shoot height, stem diameter at ground height, total biomass, size of leaves and chlorophyll fluorescence and gas exchange performance, whereas extreme level of nitrogen addition did not result in such facilitation. Chlorophyll content, pattern of biomass partitioning, ratio of leaf length to width, leaf water content, and specific leaf area did not change among the addition regimes. The critical amount of nitrogen deposition should be defined in the context of a certain time period in a particular region for a certain species at a special developmental stage. The critical amount of N deposition that weakens total biomass facilitation in A. truncatum planted in mixed soil of yellow cinnamon soil and humic soil is approximately 10 g N m−2 y−1 during the first growing season.
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