Uptake of phosphorus from different sources by Lotus pedunculatus and three genotypes of Trifolium repens .2. Forms of phosphate utilised and acidification of the rhizosphere

Soil Research ◽  
1996 ◽  
Vol 34 (6) ◽  
pp. 1027 ◽  
Author(s):  
SN Trolove ◽  
MJ Hedley ◽  
JR Caradus ◽  
AD Mackay
Keyword(s):  
North Carolina ◽  
Experimental Technique ◽  
Trifolium Repens ◽  
Inorganic Phosphorus ◽  
Phosphate Rocks ◽  
North Carolina Phosphate Rock ◽  
P Fraction ◽  
Lotus Pedunculatus ◽  
Different Sources ◽  
P Sources

Improvements in the ability of legumes to utilise applied phosphate (P) could lower fertiliser requirements. Earlier studies have found differences between legume species and genotypes of Trifolium repens in their ability to take up P from P sources that vary in solubility. Acidification of the rhizosphere may account for different P utilisation, especially from reactive phosphate rocks. To investigate differences in the ability of legumes to acidify their rhizosphere and extract various forms of P, Lotus pedunculatus and 3 genotypes of white clover that varied in their ability to respond to added P were grown in root study containers with either unfertilised soil, or soil fertilised with either monocalcium phosphate (MCP) or North Carolina phosphate rock (NCPR). After 6 weeks of plant growth, the containers were dismantled and 10 thin soil slices were taken 0-8 mm from the rhizoplane. These slices were fractionated for various P forms and pH was measured. All 4 legumes, especially lotus, acidified their rhizosphere. This resulted in negligible depletion of the small, H2SO4-P-i fraction (Pi, inorganic phosphorus) of unfertilised and MCP-fertilised soil, but caused direct dissolution of NCPR. The predominant forms of P depleted in the MCP-fertilised soil were the resin-Pi and NaOH-Pi forms, whereas in the NCPR treatment the H2SO4-Pi fraction was depleted. No significant depletion of any P fraction was observed in the unfertilised soils as plants were very small and P change in the soil slices was below that which could be measured using the experimental technique. Suggestions are made on how the experimental technique could be improved.

Uptake of phosphorus from different sources by Lotus Pedunculatus and three genotypes of Trifolium Repens .1. Plant yield and phosphate efficiency

Soil Research ◽  
1996 ◽  
Vol 34 (6) ◽  
pp. 1015 ◽  
Author(s):  
SN Trolove ◽  
MJ Hedley ◽  
JR Caradus ◽  
AD Mackay
Keyword(s):  
White Clover ◽  
Trifolium Repens ◽  
Unit Length ◽  
P Uptake ◽  
Selection Line ◽  
P Efficiency ◽  
Soil P ◽  
Lotus Pedunculatus ◽  
Unit Plant ◽  
Different Sources

The breeding of phosphate (P) efficient pastoral legumes could reduce the amount of fertiliser required on pastoral farms. In this study, Lotus pedunculatus and 3 genotypes of white clover (Trifolium repens L.) known to differ in their ability to respond to added P were grown on unfertilised soil and soil to which either monocalcium phosphate (MCP) or North Carolina phosphate rock (NCPR) were added. White clover genotype 8D (a selection line from Crau) had a greater (P < 0.05) internal P efficiency (shoot DM production per unit plant P) than 1A (a selection line from Gwenda) or lotus on unfertilised soil, whereas on fertilised soil, lotus had a significantly higher (P < 0.05) internal P efficiency than 2 of the white clover genotypes on MCP-fertilised soil (P < 0.01) and all 3 white clover genotypes on NCPR-fertlised soil (P < 0.01). Lotus also had a higher (P < 0.01) external P efficiency (total P uptake) than all 3 white clover genotypes on the 2 fertilised treatments. This was due to a greater root length, not a greater P uptake per unit length.

National Reactive Phosphate Rock Project —aims, experimental approach and site characteristics

1997 ◽  
Vol 37 (8) ◽  
pp. 885 ◽  
Author(s):  
M. J. McLaughlin ◽  
N. K. Fleming ◽  
P. G. Simpson ◽  
M. D. A. Bolland ◽  
R. J. Gilkes ◽  
...  
Keyword(s):  
North Carolina ◽  
Formic Acid ◽  
Phosphate Rock ◽  
Soil Phosphorus ◽  
Triple Superphosphate ◽  
Phosphate Rocks ◽  
Agronomic Effectiveness ◽  
North Carolina Phosphate Rock ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Summary. Field-based cutting trials, which formed part of the National Reactive Phosphate Rock Project, were established across Australia in a range of environments to evaluate the agronomic effectiveness of 5 phosphate rocks, and 1 partially acidulated phosphate rock, relative to either single superphosphate or triple superphosphate. The phosphate rocks differed in reactivity. Sechura (Bayovar) and North Carolina phosphate rocks were highly reactive (>70% solubility in 2% formic acid), whilst Khouribja (Moroccan) and Hamrawein (Egypt) phosphate rock were moderately reactive. Duchess phosphate rock from Queensland was relatively unreactive (<45% solubility in 2% formic acid). Phosphate rock effectiveness was assessed by measuring pasture production over a range of phosphorus levels, and by monitoring bicarbonate-soluble phosphorus extracted from soil samples collected before the start of each growing season. Other treatments included single large applications of triple superphosphate, partially acidulated phosphate rock and North Carolina phosphate rock applied at 2 rates, and the application of monocalcium phosphate and North Carolina phosphate rock sources without sulfur to evaluate the importance of sulfur in the potential use of phosphate rock fertilisers at each site. A broad range of environments were represented over the 30 sites which were based on pastures using annual and/or perennial legumes and perennial grasses. Rainfall across the network of sites ranged from 560 to 4320 mm, soil pH (CaCl2) from 4.0 to 5.1, and Colwell-extractable phosphorus ranged from 3 to 47 µg/g before fertiliser application. Two core experiments were established at each site. The first measured the effects of phosphate rock reactivity on agronomic effectiveness, while the second measured the effects of the degree of water solubility of the phosphorus source on agronomic effectiveness. The National Reactive Phosphate Rock Project trials gave the opportunity to confirm the suitability of accepted procedures to model fertiliser response and to develop new approaches for comparing different fertiliser responses. The Project also provided the framework for subsidiary studies such as the effect of fertiliser source on soil phosphorus extractability, cadmium and fluorine concentrations in herbage, evaluation of soil phosphorus tests, and the influence of particle size on phosphate rock effectiveness. The National Reactive Phosphate Rock Project presents a valuable model for a large, Australia-wide, collaborative team approach to an important agricultural issue. The use of standard and consistent experimental methodologies at every site ensured that maximum benefit was obtained from data generated. The aims, rationale and methods used for the experiments across the network are presented and discussed.

Bioavailability of phosphorus as a tool for efficient P reduction schemes

1998 ◽  
Vol 37 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Peter Gerdes ◽  
Sabine Kunst
Keyword(s):  
Sewage Treatment ◽  
Cost Effective ◽  
Effective Management ◽  
Lower Saxony ◽  
Effective Strategies ◽  
P Balance ◽  
Different Sources ◽  
Total P ◽  
P Sources ◽  
P Bioavailability

The bioavailability of phosphorus from different sources has been evaluated in the catchment area of the River Ilmenau (Lower-Saxony, Germany) by using algal assays. The P bioavailability describes the different potential of P from various sources of supporting eutrophication. Effluents from sewage treatment plants were highly bioavailable (72% of TP) whereas rainwater (26%) and erosion effluents (30%) showed a low bioavailability. In order to develop effective strategies to minimize P inputs into the river, source specific P bioavailability indices were determined and combined with a P balance to calculate inputs of vioavailable P (BAP) instead of total P (TP). It could be shown that the relative importance of the different P sources changes when applying BAP. Measures to reduce P inputs into the River Ilmenau will take P bioavailability into consideration and therefore lead to a more cost-effective management.

scholarly journals Estimation of Phosphorus and Nitrogen Waste in Rainbow Trout (Oncorhynchus mykiss, Walbaum, 1792) Diets Including Different Inorganic Phosphorus Sources

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1700
Author(s):  
Maria Consolación Milián-Sorribes ◽  
Ana Tomás-Vidal ◽  
David S. Peñaranda ◽  
Laura Carpintero ◽  
Juan S. Mesa ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Inorganic Phosphorus ◽  
Point Of View ◽  
Inorganic P ◽  
Monocalcium Phosphate ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Phosphorus Sources ◽  
Total P ◽  
P Sources

This study was conducted to evaluate the apparent availability and P and N excretion in rainbow trout (Oncorhynchus mykiss) using different inorganic phosphorus sources. With this goal, fish (153 ± 14.1 g) fed four inorganic P sources were assayed: monoammonium phosphate (MAP, NH4H2PO4), monosodium/monocalcium phosphate (SCP-2%, AQphos+, NaH2PO4/Ca(H2PO4)2·H2O in proportion 12/88), monosodium/monocalcium phosphate (SCP-5%, NaH2PO4/Ca(H2PO4)2·H2O in proportion 30/70) and monocalcium phosphate (MCP, Ca(H2PO4)2·H2O). Phosphorus (P) digestibility, in diets that included MAP and SCP-2% as inorganic phosphorus sources, were significantly higher than for SCP-5% and MCP sources. In relation to the P excretion pattern, independent of the diet, a peak at 6 h after feeding was registered, but at different levels depending on inorganic P sources. Fish fed an MAP diet excreted a higher amount of dissolved P in comparison with the rest of the inorganic P sources, although the total P losses were lower in MAP and SCP-2% (33.02% and 28.13, respectively) than in SCP-5% and MCP sources (43.35% and 47.83, respectively). Nitrogen (N) excretion was also studied, and the fish fed an SCP-5% diet provided lower values (15.8%) than MAP (28.0%). When N total wastes were calculated, SCP-2% and SCP-5% showed the lowest values (31.54 and 28.25%, respectively). In conclusion, based on P and N digestibility and excretion, the SCP-2% diet showed the best results from a nutritional and environmental point of view.

Uromyces trifolii-repentis Variety trifolii-repentis on Trifolium repens in North Carolina

Mycologia ◽  
1982 ◽  
Vol 74 (2) ◽  
pp. 265
Author(s):  
Ronald E. Welty ◽  
C. Gerald van Dyke ◽  
Will A. Cope
Keyword(s):  
North Carolina ◽  
Trifolium Repens

A review of the use of phosphate rocks as fertilizers for direct application in Australia and New Zealand.

1990 ◽  
Vol 30 (2) ◽  
pp. 297 ◽  
Author(s):  
NS Bolan ◽  
RE White ◽  
MJ Hedley
Keyword(s):  
North Carolina ◽  
New Zealand ◽  
Soil Ph ◽  
Western Australia ◽  
Chemical Reactivity ◽  
Field Trials ◽  
Annual Rainfall ◽  
Phosphate Rocks ◽  
Mean Annual Rainfall ◽  
Suitable Area

Field trials in New Zealand have shown that reactive phosphate rocks (RPRs) can be as effective as soluble P fertilisers, per kg of P applied, on permanent pastures that have a soil pH<6.0 (in water) and a mean annual rainfall >800 mm. Whereas RPRs such as North Carolina, Sechura, Gafsa and Chatham Rise have been evaluated on permanent pastures in New Zealand, most Australian field trials have examined unreactive PRs such as Christmas Island A and C grade, Nauru and Duchess, using annual plant species. Only in recent experiments has an RPR, North Carolina, been examined. Except on the highly leached sands in southern and south-western Australia, both reactive and unreactive PRs have shown a low effectiveness relative to superphosphate. In addition to chemical reactivity, other factors may contribute to the difference in the observed agronomic effectiveness of PRs in Australia and New Zealand. Generally, PRs have been evaluated on soils of lower pH, higher pH buffering capacity (as measured by titratable acidity) and higher P status in New Zealand than in Australia. Rainfall is more evenly distributed throughout the year on New Zealand pastures than in Australia where the soil surface dries out between rainfall events. Dry conditions reduce the rate at which soil acid diffuses to a PR granule and dissolution products diffuse away. Even when pH and soil moisture are favourable, the release of P from PR is slow and more suited to permanent pasture (i.e. the conditions usually used to evaluate PRs in New Zealand) than to the annual pastures or crops used in most Australian trials. Based on the criteria of soil pH<6.0 and mean annual rainfall >800 mm, it is estimated that the potentially suitable area for RPRs on pasture in New Zealand is about 8 million ha. Extending this analysis to Australia, but excluding the seasonal rainfall areas of northern and south-western Australia, the potentially suitable area is about 13 million ha. In New Zealand, many of the soils in the North and South Islands satisfy both the pH and rainfall criteria. However, suitable areas in Australia are confined mainly to the coastal and tableland areas of New South Wales and eastern Victoria, and within these areas the actual effectiveness of RPR will depend markedly on soil management and the distribution of annual rainfall. Further research on RPR use should be focused on these areas.

An isotope injection technique to measure agronomic effectiveness of different phosphate sources in undisturbed soils

1995 ◽  
Vol 35 (4) ◽  
pp. 489 ◽  
Author(s):  
HJ Di ◽  
R Harrison ◽  
AS Campbell
Keyword(s):  
North Carolina ◽  
Phosphate Rock ◽  
Specific Activity ◽  
P Uptake ◽  
Injection Technique ◽  
Agronomic Effectiveness ◽  
Single Superphosphate ◽  
Simple Method ◽  
North Carolina Phosphate Rock ◽  
Undisturbed Soils

This paper describes the use of an isotope injection technique for assessing the agronomic effectiveness of phosphate sources in undisturbed soils in field and glasshouse experiments. A special injection apparatus consisting of 20 syringe needles linked to a common reservoir was used to label soil cores 150 mm in diameter and 150 mm in height, without significantly disturbing the soil structure and established perennial ryegrass (Lolium perenne) root patterns. Variations in the amount of phosphorus (P) taken up by plants from single superphosphate (applied at 30, 60, and 100 kg P/ha), from 30% acidulated North Carolina phosphate rock (60 g P/ha), and from 'as received' North Carolina phosphate rock (60 kg P/ha) were indicated by the specific activity of the plant P. Percentages of plant P derived from the fertilisers were calculated on the basis of the specific activity of the fertilised treatments and the controls. The technique provides a simple method of comparing the agronomic effectiveness of phosphate sources in undisturbed soils and, unlike total dry matter yield and P uptake, is relatively unaffected by environmental factors.

Uromyces Trifolii-Repentis Variety Trifolii-Repentis on Trifolium Repens in North Carolina

Mycologia ◽  
1982 ◽  
Vol 74 (2) ◽  
pp. 265-270
Author(s):  
Ronald E. Welty ◽  
C. Gerald van Dyke ◽  
Will A. Cope
Keyword(s):  
North Carolina ◽  
Trifolium Repens
Sign in / Sign up

Export Citation Format

Share Document