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Articles 1 - 18 of 18
Full-Text Articles in Physical Sciences and Mathematics
Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock
Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock
IGC Proceedings (1997-2023)
Morphological and physiological responses of planeleaf willow (Salix planefolia Pursh.) to simulated browsing were studied under controlled conditions. The treatments consisted of every combination of three clipping intensities (30%, 60% and 90% of current twigs length removal) and three clipping timings (late winter, early spring and mid-summer). Increased clipping intensity stimulated bud activation; increased total leaf area and leaf size and increased the length of current year’s twigs. Mid-summer browsing increased the total number of leaves, the number of current twigs and decreased the length of current twigs. Higher browsing intensity resulted in higher photosynthetic rate of recently matured …
Dormant-Season Carbon Fluxes In Humid-Temperate Pastures, Howard Skinner
Dormant-Season Carbon Fluxes In Humid-Temperate Pastures, Howard Skinner
IGC Proceedings (1997-2023)
Human induced increases in atmospheric CO2 through the burning of fossil fuels and deforestation are considered to be a primary cause of rising global temperatures. However, carbon sequestration by terrestrial ecosystems has reduced the rate of CO2 accumulation in the atmosphere. Because of their vast size, grazing lands have the potential to sequester significant quantities of carbon, slowing the increase in atmospheric CO2 and reducing the risk of global warming. Although C uptake during the growing season can be substantial, losses following defoliation and drought, and during the winter months can significantly reduce annual sequestration, frequently turning …
Net Photosynthesis Rate And Chlorophyll Content Of Caucasian And White Clover Leaves Under Different Temperature Regimes, A. D. Black, R. J. Lucas, D. J. Moot
Net Photosynthesis Rate And Chlorophyll Content Of Caucasian And White Clover Leaves Under Different Temperature Regimes, A. D. Black, R. J. Lucas, D. J. Moot
IGC Proceedings (1997-2023)
In spring and summer in intensive temperate pastures, Caucasian clover (Cc) (Trifolium ambiguum) has higher dry matter (DM) production rates than white clover (wc) (Trifolium repens) (Black et al., 2003). An examination of the physiological basis for these differences can provide a greater insight into the suitability of Cc for inclusion in temperate pastures. Specifically, leaf photosynthesis rate is a major driver of seasonal growth and is strongly regulated by temperature and chlorophyll content. This study aimed to compare the net photosynthesis rate (Pn) and chlorophyll content of Cc and wc leaves under different temperature …
High Salinity Effects On The Components Of Relative Growth Rate In Rhodes Grass, E. Taleisnik, L. García Seffino, A. Córdoba, K. Grunberg, C. Arias, M. De Luca
High Salinity Effects On The Components Of Relative Growth Rate In Rhodes Grass, E. Taleisnik, L. García Seffino, A. Córdoba, K. Grunberg, C. Arias, M. De Luca
IGC Proceedings (1997-2023)
Rhodes grass (Chloris gayana Kunth), is widely cultivated in the semiarid tropics and favored for its salt tolerance. Nevertheless, productivity decreases significantly under saline conditions, especially in tetraploid cultivars. The purpose of this work was to explore, in tetraploid cultivar Boma, the physiological causes for the observed salt-associated growth reduction. The effects of high salinity (200 mM NaCl) on the components of relative growth rate were analyzed in greenhouse experiments. An early reduction in leaf area expansion was observed, which later resulted in decreased dry matter accumulation. Plant leafiness was reduced by effects both on dry matter allocation to …
Photosynthetic Light Response Of Tanzania Grass Under Four Levels Of Leaf Temperature, A. C. L. De Mello, P. M. Santos, Carlos G. S. Pedreira, M. Corsi, C. T. Dos S. Dias
Photosynthetic Light Response Of Tanzania Grass Under Four Levels Of Leaf Temperature, A. C. L. De Mello, P. M. Santos, Carlos G. S. Pedreira, M. Corsi, C. T. Dos S. Dias
IGC Proceedings (1997-2023)
The purpose of this paper is to establish photosynthetic light response curves for Tanzania grass (Panicum maximum Jacq.) under four leaf temperature levels. Photosynthetic rate was measured as a response to levels of photosynthetic photon flux density (PPFD) on the youngest fully expanded leaves of 12 representative tillers with an infra red gas analyzer. The effect of PPFD was tested for each leaf temperature level in a randomized complete block design. Photosynthetic light response curves were adjusted for each leaf temperature using a non-linear hyperbolic model. The maximum photosynthetic response was 25,59; 31,43; 34,57 and 27,53 µmol CO2 …
Effect Of The Hierarchical Position Of Individuals In A Medicago Sativa Stand On Shoot Respiration, M. Lötscher, Hans Schnyder
Effect Of The Hierarchical Position Of Individuals In A Medicago Sativa Stand On Shoot Respiration, M. Lötscher, Hans Schnyder
IGC Proceedings (1997-2023)
The influence of the hierarchical position on the relationship between C gains and C losses (respiration) of individuals was investigated in a alfalfa (Medicago sativa) stand. The hierarchical position that an individual occupied was defined by its height relative to the stand height. Stands were established by arranging potted individual plants at a density of 400 plants m-2. Stands were grown in growth cabinets. 13C steady-state labelling was used to assess C fixation (Cnew) by individuals during a photoperiod of 16 h. Respiration of shoots was measured during the following 8 h dark …
Salinity Effects On Plant Growth, Photosynthesis, And Ion Content Of Covered And Naked Oat, Guiqin Zhao, Baoluo Ma
Salinity Effects On Plant Growth, Photosynthesis, And Ion Content Of Covered And Naked Oat, Guiqin Zhao, Baoluo Ma
IGC Proceedings (1997-2023)
No abstract provided.
Carbon Balance In Stand Of An Annual Herb At An Elevated Co2 Concentration, Almaz Borjigidai, Kouki Hikosaka, Tadaki Hirose
Carbon Balance In Stand Of An Annual Herb At An Elevated Co2 Concentration, Almaz Borjigidai, Kouki Hikosaka, Tadaki Hirose
IGC Proceedings (1997-2023)
No abstract provided.
Effect Of Grazing Intensity On Photosynthesis And Soil Respiration Of Alpine Grassland In Tibet, Y. F. Wan, Q. Z. Gao, Y. Li, X. B. Qin, W. Z. Jiancun, B. S. Wang
Effect Of Grazing Intensity On Photosynthesis And Soil Respiration Of Alpine Grassland In Tibet, Y. F. Wan, Q. Z. Gao, Y. Li, X. B. Qin, W. Z. Jiancun, B. S. Wang
IGC Proceedings (1997-2023)
No abstract provided.
Effect Of Gradually Water Stress And Recovery On Photosynthesis, Transpiration, And Stomatal Conductance In Two Plantago Species, A. Rahimi, H. R. Rahimian Mashhadi, M. R. Jahansoz
Effect Of Gradually Water Stress And Recovery On Photosynthesis, Transpiration, And Stomatal Conductance In Two Plantago Species, A. Rahimi, H. R. Rahimian Mashhadi, M. R. Jahansoz
IGC Proceedings (1997-2023)
No abstract provided.
Changes Of Residue Function And Signaling Regrowth After Forage Cutting, Huimin Yang, Linag Zhao, Yuying Shen, Xiaoyan Zhang
Changes Of Residue Function And Signaling Regrowth After Forage Cutting, Huimin Yang, Linag Zhao, Yuying Shen, Xiaoyan Zhang
IGC Proceedings (1997-2023)
No abstract provided.
Changes Of Cap Of Creeping Bentgrass As Affected By Light Intensity During Summer Stress, Zhiming Yang, Zhihua Li
Changes Of Cap Of Creeping Bentgrass As Affected By Light Intensity During Summer Stress, Zhiming Yang, Zhihua Li
IGC Proceedings (1997-2023)
No abstract provided.
Photosynthesis And Transpiration Of Chicory With Different Irrigation Treatments In Beijing, Lin Meng, Yingjun Zhang, Peichun Mao, Guofang Zhang
Photosynthesis And Transpiration Of Chicory With Different Irrigation Treatments In Beijing, Lin Meng, Yingjun Zhang, Peichun Mao, Guofang Zhang
IGC Proceedings (1997-2023)
No abstract provided.
Responses Of Photosynthetic Rate Of Lucerne And The Mechanisms Under Cutting At Different Water Availabilities, Shubin He, Huimin Yang, Guoli Liu, Zhilong Zhang
Responses Of Photosynthetic Rate Of Lucerne And The Mechanisms Under Cutting At Different Water Availabilities, Shubin He, Huimin Yang, Guoli Liu, Zhilong Zhang
IGC Proceedings (1997-2023)
No abstract provided.
The Study On The Photosynthetic Characteristics Of Three Melilotoides Ruthenica Strains, Lili Zhao, Zhaolan Wang, Qingfeng Li, Jiancai Du, Xiaotao Mao
The Study On The Photosynthetic Characteristics Of Three Melilotoides Ruthenica Strains, Lili Zhao, Zhaolan Wang, Qingfeng Li, Jiancai Du, Xiaotao Mao
IGC Proceedings (1997-2023)
No abstract provided.
Alteration Of Physiological Parameters Of Milkvetch (Astragalus Adsurgens) By The Pathogen Embellisia Astragali, Binhua Yu, Zhibiao Nan
Alteration Of Physiological Parameters Of Milkvetch (Astragalus Adsurgens) By The Pathogen Embellisia Astragali, Binhua Yu, Zhibiao Nan
IGC Proceedings (1997-2023)
Milkvetch (Astragalus adsurgens) is sown on > 1 M ha in China as a forage legume and to control soil and water erosion. It is drought-tolerant and has high herbage yield, wide adaptability and medium forage quality. However, fungal disease is a major factor affecting its persistence and productivity. Embellisia astragali is a highly virulent seed-borne pathogen which commonly causes stunt and root rot. The objective of this study was to characterize the impact of Embellisia astragali on the physiological status of milkvetch by monitoring changes through time in net photosynthesis, stomatal conductance and other parameters of milkvetch inoculated …
Physiological Efficiency Of Some Weeds Species Under Hill Farming Systems Of Subtropical Meghalaya, D. P. Patel, Anup Das, G. C. Munda
Physiological Efficiency Of Some Weeds Species Under Hill Farming Systems Of Subtropical Meghalaya, D. P. Patel, Anup Das, G. C. Munda
IGC Proceedings (1997-2023)
Weeds are integral part of any farming system. Weeds are more aggressive in their ability to utilize limited moisture and nutrients in the soil relative to cultivated crops. Weeds grow more profusely in high rainfall areas such as subtropical Meghalaya owing to favourable climatic conditions which favours the growth of weeds particularly in uplands and limits the crop yields due to increased crop-weed competition for nutrients and light. The weed species such as Ageratum conyzoides, Spilanthus acmella, Galinsoga parviflora, Bidens pilosa, Crassocephalum crepidioides, Polygonum capitatum, Alternanthera philoxeroides, Amaranthus spinosus and Mikania micrantha are very common in most of the cultivated …
Improved Drought Stress Tolerance Of White Clover Through Hybridisation With Trifolium Uniflorum L., Shirley N. Nichols, Rainer W. Hofmann, Isabelle M. Verry
Improved Drought Stress Tolerance Of White Clover Through Hybridisation With Trifolium Uniflorum L., Shirley N. Nichols, Rainer W. Hofmann, Isabelle M. Verry
IGC Proceedings (1997-2023)
The objective of this study was to determine the effect of hybridisation with Trifolium uniflorum L. on drought resistance of Trifolium repens L. (white clover). Shoot dry weight of backcross 1 (BC1) hybrids was reduced less by water stress than for backcross 2 (BC2) hybrids and white clover, as were key morphological traits such as leaf area. Under water stress, important differences for the BC1 generation compared to white clover also included lower senescence, higher stolon density, increased root dry weight, and a higher maximum nodal root diameter. Drought decreased the net photosynthetic rate by up to 48% in BC2 …