Abstract
Cotton maintained free of annual grass and broadleaf weeds for 6 or more weeks after emergence in 1969 produced maximum yields, whereas in 1970 and 1971, 8 or more weeks of weed-free maintenance were required. Nitrogen applications at planting of 67 and 100 kg/ha did not influence the weed-free requirement of cotton in any year. Cotton yields were not reduced in 1969 when weeds were allowed to compete for 4 or 2 weeks. In 1970 and 1971 weed competition for 7 or fewer weeks did not result in yield reductions. Nitrogen did not affect the competitive relationship between cotton and weeds in 1969 and 1971. In 1970, however, cotton tolerated only 6 weeks of competition at the zero nitrogen rate, whereas it tolerated 7 weeks of competition at the 67 and 100 kg/ha nitrogen rates. Height and stem diameter of cotton were less reliable indicators of the crop-weed relationship than was yield. Neither height nor stem diameter of cotton revealed a consistent difference in the competitive relationship at the three nitrogen rates.
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Claims 10
Claim · model-written summary
In 1969, at least six weed-free weeks gave maximum cotton yield.
- Taxon
- Cotton
Gossypium hirsutume0 - Treatment
- free of annual grass and broadleaf weeds for 6 or more weekse0
- Interactor
- annual grass and broadleaf weedse0weed
- Outcome
- yieldse0
- Direction
- maximume0
- Value
- 6 or more weekse0
Not reportedComparatorSetting
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cotton maintained free of annual grass and broadleaf weeds for 6 or more weeks after emergence in 1969 produced maximum yields”
Claim · model-written summary
In 1970 and 1971, at least eight weed-free weeks were required for maximum yield.
- Taxon
- CottonGossypium hirsutumt0
- Outcome
- weed-free maintenancee0
- Value
- 8 or more weekse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“whereas in 1970 and 1971, 8 or more weeks of weed-free maintenance were required.”
t0“Cotton”
Claim · model-written summary
Nitrogen at 67 or 100 kg/ha did not alter the cotton weed-free requirement.
- Taxon
- cottonGossypium hirsutume0
- Treatment
- Nitrogen applications at planting of 67 and 100 kg/hae0
- Outcome
- weed-free requiremente0
- Direction
- did not influencee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen applications at planting of 67 and 100 kg/ha did not influence the weed-free requirement of cotton in any year.”
Claim · model-written summary
Cotton yield did not fall with two or four weeks of weed competition in 1969.
- Taxon
- CottonGossypium hirsutume0
- Treatment
- weeds were allowed to compete for 4 or 2 weekse0
- Interactor
- weedse0weed
- Outcome
- yieldse0
- Direction
- not reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cotton yields were not reduced in 1969 when weeds were allowed to compete for 4 or 2 weeks.”
Claim · model-written summary
Up to seven weeks of weed competition did not reduce cotton yield in 1970 or 1971.
- Taxon
- CottonGossypium hirsutumt0
- Treatment
- weed competition for 7 or fewer weekse0
- Interactor
- weede0weed
- Outcome
- yielde0
- Direction
- did not result in yield reductionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In 1970 and 1971 weed competition for 7 or fewer weeks did not result in yield reductions.”
t0“Cotton”
Claim · model-written summary
Nitrogen did not change cotton-weed competition in 1969 and 1971.
- Taxon
- cottonGossypium hirsutume0
- Treatment
- Nitrogene0
- Interactor
- weedse0weed
- Outcome
- competitive relationship between cotton and weedse0
- Direction
- did not affecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen did not affect the competitive relationship between cotton and weeds in 1969 and 1971.”
Claim · model-written summary
In 1970, cotton tolerated six weeks of weed competition without nitrogen.
- Taxon
- cottonGossypium hirsutume0
- Treatment
- zero nitrogen ratee0
- Outcome
- weeks of competitione0
- Value
- 6 weekse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“cotton tolerated only 6 weeks of competition at the zero nitrogen rate”
Claim · model-written summary
In 1970, cotton tolerated seven weeks of weed competition at 67 and 100 kg/ha nitrogen.
- Taxon
- CottonGossypium hirsutumt0
- Treatment
- 67 and 100 kg/ha nitrogen ratese0
- Outcome
- weeks of competitione0
- Value
- 7 weekse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“whereas it tolerated 7 weeks of competition at the 67 and 100 kg/ha nitrogen rates.”
t0“Cotton”
Claim · model-written summary
Height and stem diameter were less reliable indicators of cotton-weed relations than yield.
- Taxon
- cottonGossypium hirsutume0
- Outcome
- Height and stem diametere0
- Direction
- less reliablee0
- Comparator
- yielde0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Height and stem diameter of cotton were less reliable indicators of the crop-weed relationship than was yield.”
Claim · model-written summary
Cotton height and stem diameter showed no consistent difference among nitrogen rates.
- Taxon
- cottonGossypium hirsutume0
- Treatment
- three nitrogen ratese0
- Outcome
- height nor stem diametere0
- Direction
- Neithere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Neither height nor stem diameter of cotton revealed a consistent difference in the competitive relationship at the three nitrogen rates.”
The same questions in other papers
competition · yield · Gossypium hirsutum (cotton)Results differ
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- negative
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5 in the opposite direction
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23 papers in the same direction as this paper · 129 in the opposite direction
- positive
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See all 153 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.