Source and sink activity of Holcus lanatus in response to absolute and relative supply of nitrogen and phosphorus

2021 ◽  
Author(s):  
Shuqiong Wang ◽  
Jerry van Dijk ◽  
Hugo J. de Boer ◽  
Martin J. Wassen
Keyword(s):  
Holcus Lanatus ◽  
Nitrogen And Phosphorus ◽  
Sink Activity ◽  
Source And Sink

scholarly journals EFFICIENCY OF UTILIZATION OF NITROGEN AND PHOSPHORUS BY YORKSHIRE FOG (HOLCUS LANATUS)

1973 ◽  
pp. 288-302
Author(s):  
R.S.Scott A. Hardacre
Keyword(s):  
New Zealand ◽  
Perennial Ryegrass ◽  
Dry Matter ◽  
Moisture Stress ◽  
The Other ◽  
Yield Response ◽  
Holcus Lanatus ◽  
Nitrogen And Phosphorus ◽  
Climate Conditions ◽  
Pot Experiments

Two pot experiments compared the yield response and uptake of N and P by five New Zealand, two exotic ecotypes and one bred cultivar of Yorkshire fog and Ruanui perennial ryegrass under varying levels of applied N and P. One experiment was conducted in a heated glasshouse and the other under controlled climate conditions. Of the Yorkshire fog strains examined, the bred cultivar 'Massey Basyn' and an ecotype from Rotorua provided highest yields of dry matter. Their superiority was attributed in part to their ability to extract greater amounts of N and P from the soil. The former was more efficient under high levels of applied N and the latter under high levels of applied P. Under two distinct climatic environments, 'Massey Basyn' Yorkshire fog gave similar yields and uptake of N and P to Ruanui perennial ryegrass. Under a third climate, with higher temperatures and moisture stress, 'Massey Basyn' outyielded Ruanui. This was associated with a greater ability by 'Massey Basyn' to utilize absorbed P.

Colonization of a South Australian grassland by invading Mediterranean annual and perennial pasture species

1994 ◽  
Vol 45 (5) ◽  
pp. 1063 ◽  
Author(s):  
PS Cocks
Keyword(s):  
Seed Bank ◽  
Soil Seed Bank ◽  
South Australia ◽  
Principal Component ◽  
Subterranean Clover ◽  
Holcus Lanatus ◽  
Nitrogen And Phosphorus ◽  
Total Size ◽  
Broad Leaved Species ◽  
Intermediate Seeds

Spatial variation in the composition of the soil seed bank was studied in a 5 ha area of pasture in South Australia dominated by naturalized annuals originating from the Mediterranean basin. The results were analysed with regression, cluster and principal component analysis. A total of 34 species was collected, including 17 grasses, seven legumes, eight broad-leaved species and two rushes. The total size of the seed bank was over 200 seeds dm-2, equivalent to about 450 kg ha-1 Although the site was nearly flat, elevation affected the distribution of all species, probably because of its effect on drainage in winter. Five legumes (Tbifilium clusii, T. ornithopioides, T. dubium, T. glomeratum and T. subterraneum) dominated the seed bank, but the dominant species changed with elevation above the zone of winter-waterlogging. Of the grasses Serrafalcus hordeaceus and Vulpia spp. were present at well drained sites, while Lolium perenne and Hordeum geniculatum were found at low sites, with Holcus lanatus intermediate. Seeds of legumes were more frequent at sites where soil nitrogen and phosphorus were low, and seeds of grasses where they were high. The results are compared with those obtained from perennial species in north Europe, and the implications for pasture deterioration and improvement in Australia are discussed. It is concluded that genetic diversity is likely to be important in the successful invasion of pasture by Mediterranean annuals. The presence of several naturalized legumes in niches incompletely occupied by subterranean clover suggests that germplasm is available to increase the legume component of many annual pastures

scholarly journals Source and Sink Activity during Reproductive Phase of Rice (Oryza sativa L.)

2018 ◽  
Vol 7 (11) ◽  
pp. 3632-3639
Author(s):  
P. Venkata Narayana ◽  
B. Sreekanth ◽  
Y. Ashoka Rani ◽  
B. Krishnaveni
Keyword(s):  
Oryza Sativa ◽  
Oryza Sativa L ◽  
Reproductive Phase ◽  
Sink Activity ◽  
Source And Sink

scholarly journals Thermal acclimation of leaf respiration as a way to reduce source–sink imbalance at low temperatures in Erythronium americanum, a spring ephemeral

Botany ◽  
2018 ◽  
Vol 96 (2) ◽  
pp. 97-109
Author(s):  
Yanwen Dong ◽  
Dominique Gérant ◽  
Line Lapointe
Keyword(s):  
Low Temperatures ◽  
Dark Respiration ◽  
Temperature Acclimation ◽  
Respiratory Pathway ◽  
Spring Ephemeral ◽  
Sink Activity ◽  
Leaf Dark Respiration ◽  
Erythronium Americanum ◽  
Source Sink ◽  
Source And Sink

Many spring geophytes exhibit greater growth at colder than at warmer temperatures. Previous studies have suggested that there is less disequilibrium between source and sink activity at low temperatures, which delays leaf senescence and leads to higher accumulation of biomass in the perennial organ. We hypothesized that dark respiration acclimates to temperature at both the leaf and bulb levels, mainly via the alternative respiratory pathway, as a way to reduce source–sink imbalance. Erythronium americanum Ker-Gawl. was grown under three temperature regimes: 8/6 °C, 12/8 °C, and 18/14 °C (day/night). Plant respiratory rates were measured at both growth and common temperatures to determine whether differences were due to the direct effects of temperature on respiratory rates or to acclimation. Leaf dark respiration exhibited homeostasis, which together with lower assimilation at low growth temperature, most likely reduced the quantity of C available for translocation to the bulb. No temperature acclimation was visible at the sink level. However, bulb total respiration varied through time, suggesting potential stimulation of bulb respiration as sink limitation builds up. In conclusion, acclimation of respiration at the leaf level could partly explain the better equilibrium between source and sink activity in plants grown in low-temperatures, whereas bulb respiration responds to source–sink imbalance.

Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels

2020 ◽  
Vol 85 ◽  
pp. 47-58
Author(s):  
Y Jiang ◽  
Y Liu
Keyword(s):  
Microcystis Aeruginosa ◽  
Regulatory Protein ◽  
Acid Synthesis ◽  
Nutrient Supply ◽  
Nitrogen Supply ◽  
Nitrogen And Phosphorus ◽  
Comprehensive Description ◽  
Amino Acid Synthesis ◽  
High Nutrient ◽  
Proteomic Responses

Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.

Method application of optimal multi-parameter analysis to assess the distribution of water masses as an example of CTD data of the Barents Sea in summer 2017

2019 ◽  
pp. 38-51
Author(s):  
Valeriy G. Yakubenko ◽  
Anna L. Chultsova
Keyword(s):  
Barents Sea ◽  
Field Measurements ◽  
Structural Similarity ◽  
Water Masses ◽  
Parameter Analysis ◽  
Water Dynamics ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
The Barents Sea ◽  
Expert Assessments

Identification of water masses in areas with complex water dynamics is a complex task, which is usually solved by the method of expert assessments. In this paper, it is proposed to use a formal procedure based on the application of the method of optimal multiparametric analysis (OMP analysis). The data of field measurements obtained in the 68th cruise of the R/V “Academician Mstislav Keldysh” in the summer of 2017 in the Barents Sea on the distribution of temperature, salinity, oxygen, silicates, nitrogen, and phosphorus concentration are used as a data for research. A comparison of the results with data on the distribution of water masses in literature based on expert assessments (Oziel et al., 2017), allows us to conclude about their close structural similarity. Some differences are related to spatial and temporal shifts of measurements. This indicates the feasibility of using the OMP analysis technique in oceanological studies to obtain quantitative data on the spatial distribution of different water masses.

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