The response of organic and conventionally grown wheat to superphosphate and reactive phosphate rock

1996 ◽  
Vol 36 (1) ◽  
pp. 71 ◽  
Author(s):  
PR Dann ◽  
JW Derrick ◽  
DC Dumaresq ◽  
MH Ryan
Keyword(s):  
Grain Yield ◽  
Mycorrhizal Fungi ◽  
Phosphate Rock ◽  
Arbuscular Mycorrhizal ◽  
Dry Weight ◽  
Reactive Phosphate ◽  
South Wales ◽  
Large Yield ◽  
Reactive Phosphate Rock ◽  
P Content

In 1991 and 1992 wheat was sown on adjacent properties at Ardlethan in southern New South Wales to assess its response to superphosphate (SP) and reactive phosphate rock (RPR) under conventional and organic management systems. Five rates of P (0, 10, 20, 30, 40 kg/ha) were applied as SP and RPR. No response to RPR was recorded in terms of crop growth or grain yield. However, in both years and on both sites, SP significantly increased plant dry weight at tillering and anthesis, the number of tillers and spikes per plant and grain yield. Superphosphate also increased the P content of grain and the amount of P exported. SP (40 kg P/ha) increased the level of cadmium in the grain, although not beyond permitted maximum concentrations. The use of SP reduced the level of colonisation by vesicular-arbuscular mycorrhizal fungi (VAM). The data indicate that the choice of the organic farmer, not to use SP, incurs a large yield penalty.

Assessment of soil phosphorus tests for situations in Australia where reactive phosphate rock and water-soluble phosphorus fertilisers are used

1997 ◽  
Vol 37 (8) ◽  
pp. 1027 ◽  
Author(s):  
P. G. Simpson ◽  
M. J. McLaughlin ◽  
A. J. Weatherley ◽  
P. W. G. Sale ◽  
V. Hoy ◽  
...  
Keyword(s):  
Phosphate Rock ◽  
Soil Phosphorus ◽  
Subterranean Clover ◽  
Soil Test ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
P Content ◽  
Soil Test P ◽  
The Relationship ◽  
Bray 1

Summary. A selection of commonly used soil phosphorus (P) tests, which included anion and cation exchange resin membranes, were compared in a glasshouse experiment using subterranean clover, and evaluated in the field at 19 sites from the National Reactive Phosphate Rock Project in 1993 and at 6 sites in 1995. The ability of the soil P tests to predict plant response was used to evaluate the tests. In the glasshouse experiment the resin test was less effective than the Bray 1 and Colwell tests in its ability to assess the level of plant-available P from the different fertiliser treatments. Seventy-one percent of the variation in total P content of the subterranean clover shoots was explained by resin-extractable P values, whereas the Colwell procedure accounted for 81% and the Bray 1 procedure accounted for 78%. Water and CaCl2 extracts were poor predictors of P content. In the field experiments all tests evaluated performed poorly in describing the relationship between soil test P and the level of P applied and relative yield and soil test P over a wide range of soil types and environments. The Bray 1 procedure performed best but the relationship was poor.

A glasshouse evaluation of sulfur fertilizer sources for crops and pastures. III. Soluble and non-soluble sulfur and phosphorus sources for pastures

1994 ◽  
Vol 45 (7) ◽  
pp. 1525 ◽  
Author(s):  
RDB Lefroy ◽  
M Dana ◽  
GJ Blair
Keyword(s):  
Phosphate Rock ◽  
Nutrient Release ◽  
Field Capacity ◽  
Undisturbed Soil ◽  
Fertilizer Use ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
P Content ◽  
Use Efficiency ◽  
P Application

Decreasing terms of trade of animal producers and increasing awareness of environmental problems associated with fertilizer use has resulted in increased emphasis on improving fertilizer use efficiency. Elemental S and reactive phosphate rock offer two sources of fertilizers with slower nutrient release rates than gypsum or monocalcium phosphate. A randomized block experiment was conducted under glasshouse conditions. Undisturbed soil cores of an Aquic Haplustalf soil were oversown with perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens, L.), and a factorial combination of two S sources (elemental S and gypsum), two P sources (triple superphosphate, (TSP), or North Carolina reactive phosphate rock (RPR), two methods of S and P application (S mixed with granulated TSP or RPR and S coated onto TSP or granulated RPR). An unfertilized control (C) was included in order to calculate fertilizer S recovery using the 35S reverse dilution technique. Pots were either watered to field capacity (NL) or watered to 25% excess to promote leaching (L). Harvests of tops were made at 4 or 8 weekly intervals up to 96 weeks after application when the pots were destructively harvested. Yields were lower in the leached than the unleached pots between weeks 8 and 44 where TSP or G was applied. Clover yields were initially highest with G, but elemental S gave more sustained production. Yields and P content of tops were lower with RPR than TSP up to week 36. Recovery of fertilizer S was higher in the TSP than RPR treatments up to week 24. Leaching losses of S were higher from G than elemental S sources up to week 17 and were higher where TSP was the P source. Manipulation of P and S source has been shown to improve the efficiency of utilization of the applied fertilizers.

scholarly journals Direct application of reactive phosphate rock on improving maize yield in tidal swampland

2021 ◽  
Vol 648 (1) ◽  
pp. 012175
Author(s):  
A F Siregar ◽  
Husnain ◽  
I W Suastika ◽  
N P S Ratmini ◽  
I A Sipahutar ◽  
...  
Keyword(s):  
Phosphate Rock ◽  
Maize Yield ◽  
Direct Application ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

Yield response in chickpea cultivars and wheat following crop rotations affecting population densities of Pratylenchus thornei and arbuscular mycorrhizal fungi

2014 ◽  
Vol 65 (5) ◽  
pp. 428 ◽  
Author(s):  
R. A. Reen ◽  
J. P. Thompson ◽  
T. G. Clewett ◽  
J. G. Sheedy ◽  
K. L. Bell
Keyword(s):  
Grain Yield ◽  
Crop Rotation ◽  
Mycorrhizal Fungi ◽  
Soil Depth ◽  
Arbuscular Mycorrhizal ◽  
Yield Response ◽  
First Year ◽  
Pratylenchus Thornei ◽  
Tolerance Indices ◽  
Chickpea Cultivars

In Australia, root-lesion nematode (RLN; Pratylenchus thornei) significantly reduces chickpea and wheat yields. Yield losses from RLN have been determined through use of nematicide; however, nematicide does not control nematodes in Vertosol subsoils in Australia’s northern grains region. The alternative strategy of assessing yield response, by using crop rotation with resistant and susceptible crops to manipulate nematode populations, is poorly documented for chickpea. Our research tested the effectiveness of crop rotation and nematicide against P. thornei populations for assessing yield loss in chickpea. First-year field plots included canola, linseed, canaryseed, wheat and a fallow treatment, all with and without the nematicide aldicarb. The following year, aldicarb was reapplied and plots were re-cropped with four chickpea cultivars and one intolerant wheat cultivar. Highest P. thornei populations were after wheat, at 0.45–0.6 m soil depth. Aldicarb was effective to just 0.3 m for wheat and 0.45 m for other crops, and increased subsequent crop grain yield by only 6%. Canola, linseed and fallow treatments reduced P. thornei populations, but low mycorrhizal spore levels in the soil after canola and fallow treatments were associated with low chickpea yield. Canaryseed kept P. thornei populations low throughout the soil profile and maintained mycorrhizal spore densities, resulting in grain yield increases of up to 25% for chickpea cultivars and 55% for wheat when pre-cropped with canaryseed compared with wheat. Tolerance indices for chickpeas based on yield differences after paired wheat and canaryseed plots ranged from 80% for cv. Tyson to 95% for cv. Lasseter and this strategy is recommended for future use in assessing tolerance.

The agronomic effectiveness of reactive phosphate rocks 1. Effect of the pasture environment

1997 ◽  
Vol 37 (8) ◽  
pp. 921 ◽  
Author(s):  
P. W. G Sale ◽  
R. J. Gilkes ◽  
M. D. A. Bolland ◽  
P. G. Simpson ◽  
D. C. Lewis ◽  
...  
Keyword(s):  
North Carolina ◽  
Phosphate Rock ◽  
Surface Soil ◽  
Annual Rainfall ◽  
Triple Superphosphate ◽  
Agronomic Effectiveness ◽  
P Sorption ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
Very High

Summary. The agronomic effectiveness of directly applied North Carolina reactive phosphate rock was determined for 4 years from annual dry matter responses at 26 permanent pasture sites across Australia as part of the National Reactive Phosphate Rock Project. Fertiliser comparisons were based on the substitution value of North Carolina reactive phosphate rock for triple superphosphate (the SV50). The SV50 was calculated from fitted response curves for both fertilisers at the 50% of maximum yield response level of triple superphosphate. The reactive phosphate rock was judged to be as effective as triple superphosphate in the 1st year (and every year thereafter) at 4 sites (SV50 >0.9), and was as effective by the 4th year at 5 sites. At another 9 sites the reactive phosphate rock was only moderately effective with SV50 values between 0.5 and 0.8 in the 4th year, and at the final 8 sites it performed poorly with the 4th year SV50 being less than 0.5. Pasture environments where the reactive phosphate rock was effective in the 1st year were: (i) those on sandy, humic or peaty podsols with an annual rainfall in excess of 850 mm; (ii) those on soils that experienced prolonged winter inundation and lateral surface flow; and (iii) tropical grass pastures in very high rainfall areas (>2300 mm) on the wet tropical coast on North Queensland. The highly reactive North Carolina phosphate rock became effective by the 4th year at sites in southern Australia where annual rainfall exceeded 700 mm, and where the surface soil was acidic [pH (CaCl2) <5.0] and not excessively sandy (sand fraction in the A1 horizon <67%) but had some phosphorus (P) sorption capacity. Sites that were unsuitable for reactive phosphate rock use in the medium term (up to 4 years at least) were on very high P-sorbing krasnozem soils or high P-sorbing lateritic or red earth soils supporting subterranean-clover-dominant pasture, or on lower rainfall (< 600 mm) pastures growing on soils with a sandy A1 horizon (sand component >84%). No single environmental feature adequately predicted reactive phosphate rock performance although the surface pH of the soil was most closely correlated with the year-4 SV50 (r = 0.67). Multiple linear regression analysis found that available soil P (0–10 cm) and the P sorption class of the surface soil (0–2 cm), together with annual rainfall and a measure of the surface soil"s ability to retain moisture, could explain about two-thirds of the variance in the year-4 SV50 . The results from this Project indicate that there are a number of specific pasture environments in the higher rainfall regions of Australia where North Carolina reactive phosphate rock can be considered as an effective substitute P fertiliser for improved pasture.

Response of Taxus times media var. densiformis to inoculation with arbuscular mycorrhizal fungi

1998 ◽  
Vol 28 (1) ◽  
pp. 150-153
Author(s):  
J N Gemma ◽  
R E Koske ◽  
E M Roberts ◽  
S Hester
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Arbuscular Mycorrhizal ◽  
Dry Weight ◽  
Root Systems ◽  
Stem Diameter ◽  
Rooted Cuttings ◽  
Shoot Dry Weight ◽  
Mycorrhizal Plants

Rooted cuttings of Taxus times media var. densiformis Rehd. were inoculated with the arbuscular mycorrhizal fungi Gigaspora gigantea (Nicol. & Gerd.) Gerd. & Trappe or Glomus intraradices Schenck and Smith and grown for 9-15 months in a greenhouse. At the completion of the experiments, leaves of inoculated plants contained significantly more chlorophyll (1.3-4.1 times as much) than did noninoculated plants. In addition, mycorrhizal plants had root systems that were significantly larger (1.3-1.4 times) and longer (1.7-2.1 times) than nonmycorrhizal plants, and they possessed significantly more branch roots (1.3-2.9 times). No differences in stem diameter and height or shoot dry weight were evident at the end of the experiments, although the number of buds was significantly greater in the cuttings inoculated with G. intraradices after 15 months.

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