Abstract
The maintenance of optimum mineral nutrient fertility is a limiting factor in organic vegetable systems, with many growers resorting to applications of off-farm commercial fertilizer inputs. In this study, pelleted sheep’s wool was compared against a standard commercial fertilizer product for effects on productivity and plant growth in spinach and tomato. Two rates of wool pellets were applied; one was standardized to the nitrogen inputs of the ‘grower standard’ commercial treatment, and a second higher rate which was suggested by the pellet manufacturer with about 2.5 times the nitrogen content. Overall, few differences were observed among the fertilized treatments. Crop yield for both tomato and spinach generally increased with increasing fertility application, with no differences between commercial and wool pellet fertilizers applied at the same rate of nitrogen. The uptake of mineral nutrients in spinach plant tissues differed for K, Mg, P, S, B, and Ca, but there was no general trend that could be attributed to a particular treatment. Tomato fruit quality was the same for all treatments, but non-fertilized fruit had lower total polyphenols than the highest-fertility treatment. Overall, wool pellets performed very similarly to commercial organic fertilizer for both crops and could be a promising alternative that may open up opportunities for greater integration of plant and animal systems on diversified farms.
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Claims 10
Claim · model-written summary
Tomato yield generally increased with increasing fertilizer application.
- Taxon
- tomato
Solanum lycopersicume0 - Treatment
- increasing fertility applicatione0
- Outcome
- Crop yielde0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Crop yield for both tomato and spinach generally increased with increasing fertility application”
Claim · model-written summary
Spinach yield generally increased with increasing fertilizer application.
- Taxon
- spinach
Spinacia oleraceae0 - Treatment
- increasing fertility applicatione0
- Outcome
- Crop yielde0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Crop yield for both tomato and spinach generally increased with increasing fertility application”
Claim · model-written summary
Tomato yield did not differ between commercial and wool fertilizers at equal nitrogen rates.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- wool pellet fertilizerse0
- Outcome
- Crop yielde1
- Direction
- no differencese0
- Qualifier
- same rate of nitrogene0
- Comparator
- commerciale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“no differences between commercial and wool pellet fertilizers applied at the same rate of nitrogen”
e1“Crop yield for both tomato and spinach”
Claim · model-written summary
Spinach yield did not differ between commercial and wool fertilizers at equal nitrogen rates.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- wool pellet fertilizerse0
- Outcome
- Crop yielde1
- Direction
- no differencese0
- Qualifier
- same rate of nitrogene0
- Comparator
- commerciale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“no differences between commercial and wool pellet fertilizers applied at the same rate of nitrogen”
e1“Crop yield for both tomato and spinach”
Claim · model-written summary
Spinach tissue K, Mg and P uptake differed among treatments without a consistent treatment trend.
- Taxon
- spinachSpinacia oleraceae0
- Organ / stage
- plant tissuese0
- Outcome
- uptake of mineral nutrientse0
- Qualifier
- no general trend that could be attributed to a particular treatmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The uptake of mineral nutrients in spinach plant tissues differed for K, Mg, P, S, B, and Ca, but there was no general trend that could be attributed to a particular treatment”
Claim · model-written summary
Tomato fruit quality was the same across treatments.
- Taxon
- TomatoSolanum lycopersicume0
- Treatment
- all treatmentse0
- Outcome
- fruit qualitye0
- Direction
- samee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tomato fruit quality was the same for all treatments”
Claim · model-written summary
Unfertilized tomato fruit had lower total polyphenols than fruit under the highest fertility.
- Taxon
- TomatoSolanum lycopersicume1
- Treatment
- non-fertilizede0
- Outcome
- total polyphenolse0
- Direction
- lowere0
- Comparator
- highest-fertility treatmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“non-fertilized fruit had lower total polyphenols than the highest-fertility treatment”
e1“Tomato fruit quality”
Claim · model-written summary
Wool pellets performed similarly to commercial organic fertilizer for tomato.
- Taxon
- tomatoSolanum lycopersicume1
- Outcome
- performed very similarlye0
- Comparator
- commercial organic fertilizere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“wool pellets performed very similarly to commercial organic fertilizer for both crops”
e1“spinach and tomato”
Claim · model-written summary
Wool pellets performed similarly to commercial organic fertilizer for spinach.
- Taxon
- spinachSpinacia oleraceae1
- Outcome
- performed very similarlye0
- Comparator
- commercial organic fertilizere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“wool pellets performed very similarly to commercial organic fertilizer for both crops”
e1“spinach and tomato”
Claim · model-written summary
The authors propose wool pellets as a promising alternative for diversified farms.
- Taxon
- spinachSpinacia oleraceae1
- Outcome
- promising alternativee0
- Qualifier
- diversified farmse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“wool pellets performed very similarly to commercial organic fertilizer for both crops and could be a promising alternative that may open up opportunities for greater integration of plant and animal systems on diversified farms”
e1“spinach and tomato”
The same questions in other papers
fertilization · yield · Spinacia oleracea (spinach)Results differ
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- positive
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See all 79 papers →fertilization · yield · Solanum lycopersicum (tomato)Positive and negative results
127 papers in the same direction as this paper · 850 in the opposite direction
- positive
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See all 978 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.