Abstract
At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol) for 4 years and sorghum was grown in the sixth year, after an 18-month fallow. The initial bicarbonate-extractable soil phosphorus (P) concentration was 6 mg/kg in the 0-20 cm horizon. High analysis superphosphate (19.2% P) was broadcast at 0-180 kg P/ha in the first year, and banded rates of 0-20 kg P/ha were superimposed on the broadcast rates of 0-60 kg P/ha each year except in the fifth (fallow) year. Sorghum dry matter (DM) yields at anthesis, summed over 5 seasons, increased linearly (P<0.05) with both methods of P application, but significant (P<0.05) treatment differences occurred only after the 18 months of fallow. Total sorghum grain yields after 5 seasons fitted a quadratic reponse curve (P<0.05) with both application methods. Sunflower DM yields at anthesis increased significantly (P<0.05) with broadcast fertiliser in the first season only, but neither the rate nor the method of application of fertiliser affected seed yields over 4 seasons. Seed P concentrations for both crops were either unaffected or increased with increasing rates of fertiliser. Fertiliser P may not be needed for sunflower, but we recommend banding about 70 kg P/ha with sorghum at sowing over 5 years to ensure maximum yields. Based on extractable P values, the relative effectiveness of initial broadcast and incorporated P applications exceeding 40 kg/ha declined over the first 4 years, but then tended to remain steady at about 0.67. There was no consistent trend in relative effectiveness with time at the lower rates of P application.
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Claims 12
Claim · model-written summary
Sorghum DM yield at anthesis increased linearly with both P application methods
- Treatment
- both methods of P applicatione1
- Outcome
- Sorghum dry matter (DM) yields at anthesise1
- Direction
- increased linearlye1
- Setting
- Emerald in central Queenslande0
SorghumNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e1“Sorghum dry matter (DM) yields at anthesis, summed over 5 seasons, increased linearly (P<0.05) with both methods of P application”
Claim · model-written summary
Significant sorghum treatment differences occurred only after the 18 months of fallow
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e2“but significant (P<0.05) treatment differences occurred only after the 18 months of fallow”
Claim · model-written summary
Total sorghum grain yield over five seasons fitted a quadratic response curve with both application methods
- Treatment
- both application methodse3
- Outcome
- Total sorghum grain yieldse3
- Qualifier
- quadratic reponse curvee3
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e3“Total sorghum grain yields after 5 seasons fitted a quadratic reponse curve (P<0.05) with both application methods”
Claim · model-written summary
Sunflower DM yield at anthesis increased with broadcast fertiliser in the first season only
- Taxon
- sunflower
Helianthus annuuse0 - Treatment
- broadcast fertilisere4
- Outcome
- Sunflower DM yields at anthesise4
- Direction
- increasede4
- Qualifier
- in the first season onlye4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e4“Sunflower DM yields at anthesis increased significantly (P<0.05) with broadcast fertiliser in the first season only”
Claim · model-written summary
Neither the rate nor the method of fertiliser application affected sunflower seed yield over 4 seasons
- Taxon
- sunflowerHelianthus annuuse0
- Treatment
- rate nor the method of application of fertilisere5
- Outcome
- seed yieldse5
- Direction
- no_changeinferrede5
- Qualifier
- over 4 seasonse5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e5“neither the rate nor the method of application of fertiliser affected seed yields over 4 seasons”
Claim · model-written summary
Sorghum seed P concentration was unaffected or increased with increasing fertiliser rates
- Treatment
- increasing rates of fertilisere6
- Outcome
- Seed P concentrationse6
- Direction
- unaffected or increasede6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e6“Seed P concentrations for both crops were either unaffected or increased with increasing rates of fertiliser”
Claim · model-written summary
Sunflower seed P concentration was unaffected or increased with increasing fertiliser rates
- Taxon
- sunflowerHelianthus annuuse0
- Treatment
- increasing rates of fertilisere6
- Outcome
- Seed P concentrationse6
- Direction
- unaffected or increasede6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e6“Seed P concentrations for both crops were either unaffected or increased with increasing rates of fertiliser”
Claim · model-written summary
Fertiliser P may not be needed for sunflower
- Taxon
- sunflowerHelianthus annuuse0
- Outcome
- Fertiliser Pe7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e7“Fertiliser P may not be needed for sunflower”
Claim · model-written summary
Banding about 70 kg P/ha with sorghum at sowing over 5 years is recommended for maximum yields
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“we recommend banding about 70 kg P/ha with sorghum at sowing over 5 years to ensure maximum yields”
Claim · model-written summary
Relative effectiveness of broadcast and incorporated P applications above 40 kg/ha declined over the first 4 years
- Treatment
- initial broadcast and incorporated P applicationse1
- Outcome
- relative effectivenesse1
- Direction
- declinede1
- Qualifier
- exceeding 40 kg/hae1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e1“Based on extractable P values, the relative effectiveness of initial broadcast and incorporated P applications exceeding 40 kg/ha declined over the first 4 years”
Claim · model-written summary
Relative effectiveness of P applications then remained steady at about 0.67
- Treatment
- initial broadcast and incorporated P applicationse1
- Outcome
- relative effectivenesse1
- Direction
- remain steadye2
- Value
- about 0.67e2
- Qualifier
- exceeding 40 kg/hae1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e1“Based on extractable P values, the relative effectiveness of initial broadcast and incorporated P applications exceeding 40 kg/ha declined over the first 4 years”
e2“but then tended to remain steady at about 0.67”
Claim · model-written summary
No consistent trend in relative effectiveness over time at lower P rates
- Treatment
- lower rates of P applicatione1
- Outcome
- relative effectivenesse1
- Direction
- no consistent trende1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At Emerald in central Queensland, dryland sorghum and sunflower were grown on a cracking clay soil (Vertisol)”
e1“There was no consistent trend in relative effectiveness with time at the lower rates of P application”
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See all 365 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.