Abstract
Density and spatial interference of barnyardgrass with ‘Lemont’ and ‘Newbonnet’ rice cultivars was investigated in 1987 and 1988. Barnyardgrass reduced grain yield of Lemont, a semidwarf cultivar, more than Newbonnet, a short-statured cultivar. Linear regression indicated that season-long interference of barnyardgrass at 1 to 20 plants m –2 reduced grain yields of Lemont and Newbonnet by 301 and 257 kg ha –1 per barnyardgrass plant, respectively. Grain yields of Lemont and Newbonnet were reduced by barnyardgrass densities to 40 plants m –2 but were not affected further at densities ≥40 plants m –2 . Barnyardgrass reduced straw yield of Lemont more than of Newbonnet. Although barnyardgrass culms m –2 and straw yield increased as weed density increased, the weed produced more culms per plant at 2 and 5 m –2 than at 20 to 80 m –2 . In a spatial interference experiment, Lemont grain yield reduction averaged 21% when plants were grown within 0 to 25 cm of a barnyardgrass plant group (group = 4 plants per 140 cm 2 ). However, rice yields were not reduced when barnyardgrass plant groups were 25 to 50 or 50 to 100 cm away. Additional treatments included two barnyardgrass groups spaced 20, 40, 80, or 100 cm apart When Lemont grew between barnyardgrass groups spaced 20 or 40 cm apart, grain yields were reduced 40 and 27%, respectively, compared with weed-free rice. However, Lemont yield was not reduced when rice plants grew between weed plant groups spaced 100 cm apart.
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Claims 13
Claim · model-written summary
Barnyardgrass reduced Lemont grain yield more than Newbonnet grain yield.
- Taxon
- Rice
Oryza sativae0t0 - Interactor
- Barnyardgrass
Echinochloa crus-gallie0t0weed
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Barnyardgrass reduced grain yield of Lemont, a semidwarf cultivar, more than Newbonnet, a short-statured cultivar.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Season-long barnyardgrass interference reduced Lemont grain yield by 301 kg ha –1 per weed plant.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Linear regression indicated that season-long interference of barnyardgrass at 1 to 20 plants m –2 reduced grain yields of Lemont and Newbonnet by 301 and 257 kg ha –1 per barnyardgrass plant, respectively.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Season-long barnyardgrass interference reduced Newbonnet grain yield by 257 kg ha –1 per weed plant.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Linear regression indicated that season-long interference of barnyardgrass at 1 to 20 plants m –2 reduced grain yields of Lemont and Newbonnet by 301 and 257 kg ha –1 per barnyardgrass plant, respectively.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Barnyardgrass density up to 40 plants m –2 reduced Lemont and Newbonnet grain yields.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain yields of Lemont and Newbonnet were reduced by barnyardgrass densities to 40 plants m –2”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Grain yields were not further affected above 40 barnyardgrass plants m –2.
- Taxon
- RiceOryza sativae0t0e1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“were not affected further at densities ≥40 plants m –2”
t0“Rice (Oryza sativa)”
e1“Grain yields of Lemont and Newbonnet were reduced by barnyardgrass densities to 40 plants m –2”
Claim · model-written summary
Barnyardgrass reduced Lemont straw yield more than Newbonnet straw yield.
- Taxon
- RiceOryza sativae0t0
- Interactor
- BarnyardgrassEchinochloa crus-gallie0t0weed
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Barnyardgrass reduced straw yield of Lemont more than of Newbonnet.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Barnyardgrass culm density and straw yield increased with weed density.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“barnyardgrass culms m –2 and straw yield increased as weed density increased”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Barnyardgrass made more culms per plant at 2 and 5 m –2 than at 20 to 80 m –2.
- Taxon
- RiceOryza sativae0t0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the weed produced more culms per plant at 2 and 5 m –2 than at 20 to 80 m –2”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Lemont grain yield fell 21% within 0 to 25 cm of a barnyardgrass group.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lemont grain yield reduction averaged 21% when plants were grown within 0 to 25 cm of a barnyardgrass plant group”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Rice yields were not reduced with barnyardgrass groups 25 to 100 cm away.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice yields were not reduced when barnyardgrass plant groups were 25 to 50 or 50 to 100 cm away”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Lemont yield fell 40% with barnyardgrass groups 20 cm apart versus weed-free rice.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When Lemont grew between barnyardgrass groups spaced 20 or 40 cm apart, grain yields were reduced 40 and 27%, respectively, compared with weed-free rice.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Lemont yield fell 27% with barnyardgrass groups 40 cm apart versus weed-free rice.
- Taxon
- RiceOryza sativae0t0
- Interactor
- barnyardgrassEchinochloa crus-gallie0t0weed
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When Lemont grew between barnyardgrass groups spaced 20 or 40 cm apart, grain yields were reduced 40 and 27%, respectively, compared with weed-free rice.”
t0“Rice (Oryza sativa)”
Claim · model-written summary
Lemont yield was not reduced at 100 cm between weed groups.
- Taxon
- RiceOryza sativae0t0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lemont yield was not reduced when rice plants grew between weed plant groups spaced 100 cm apart.”
t0“Rice (Oryza sativa)”
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See all 172 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.