Abstract
In continuation of earlier work, a study has been made of the factors controlling the competition between spring-sown cereals and annual weeds. During the years 1934 and 1935 some eighteen replicated trials were carried out in widely different localities. In six experiments, observations involving some 20,000 counts were made on the cereal development. Competition between Brassica arvensis (yellow charlock) and spring barley primarily reduced the number of tillers and fertile shoots; competition on the other hand with Raphanus raphanistrum (white charlock) diminished in addition ear size. The presence of R. raphanistrum in spring oats may decrease panicle size to the same extent as shoot number. In four out of six experiments the addition of nitrogen to both the weedy and clean crop had similar effects, greatly increasing tiller production in barley and both panicle size and shoot number in oats. In six experiments nitrogenous manuring raised the yield of the weedy crop (containing either B. arvensis, R. raphanistrum or Chrysanthemum segetum (corn marigold)) to or above the level of the clean crop; n i four the yield increases were greater in the weedy than in the weed-free crop. In one experiment doubling the amount of nitrogen applied to the weedy crop did not increase the yield of oats more than the single rate, although the final yield level was considerably below that of the weed-free oats. In four other experiments additional nitrogen did not raise the yield of the weedy crop; but in only one was the yield of the clean crop increased by nitrogenous manuring.
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Claims 10
Claim · model-written summary
Brassica arvensis competition reduced barley tillers and fertile shoots.
- Taxon
- spring barley
.jpg?width=60)
Hordeum vulgaree0 - Treatment
- Competition between Brassica arvensis (yellow charlock) and spring barleye0
- Interactor
- Brassica arvensis
Moricandia arvensise0weed - Outcome
- number of tillers and fertile shootse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Competition between Brassica arvensis (yellow charlock) and spring barley primarily reduced the number of tillers and fertile shoots”
Claim · model-written summary
Raphanus raphanistrum competition reduced barley ear size.
- Treatment
- competition on the other hand with Raphanus raphanistrume0
- Interactor
- Raphanus raphanistrum
_Raphanus_raphanistrum_-_flowers.jpg?width=60)
Raphanus raphanistrume0weed - Outcome
- ear sizee0
- Direction
- diminishede0
Not reportedTaxonComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
_Raphanus_raphanistrum_-_flowers.jpg?width=500)
Verbatim
e0“competition on the other hand with Raphanus raphanistrum (white charlock) diminished in addition ear size”
Claim · model-written summary
Raphanus raphanistrum presence in oats may reduce panicle size as much as shoot number.
- Taxon
- spring oats
Avena sativae0 - Treatment
- presence of R. raphanistrume0
- Interactor
- R. raphanistrumRaphanus raphanistrume0weed
- Outcome
- panicle sizee0
- Direction
- decreasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The presence of R. raphanistrum in spring oats may decrease panicle size to the same extent as shoot number”
Claim · model-written summary
Nitrogen increased tiller production in barley in four of six experiments.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- addition of nitrogene0
- Outcome
- tiller productione0
- Direction
- increasinge0
- Qualifier
- In four out of six experimentse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In four out of six experiments the addition of nitrogen to both the weedy and clean crop had similar effects, greatly increasing tiller production in barley and both panicle size and shoot number in oats”
Claim · model-written summary
Nitrogen increased panicle size and shoot number in oats in four of six experiments.
- Taxon
- oatsAvena sativae0
- Treatment
- addition of nitrogene0
- Outcome
- panicle size and shoot numbere0
- Direction
- increasinge0
- Qualifier
- In four out of six experimentse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In four out of six experiments the addition of nitrogen to both the weedy and clean crop had similar effects, greatly increasing tiller production in barley and both panicle size and shoot number in oats”
Claim · model-written summary
Nitrogen raised yields of weedy crops to or above clean crop yields in six experiments.
Verbatim
e0“In six experiments nitrogenous manuring raised the yield of the weedy crop (containing either B. arvensis, R. raphanistrum or Chrysanthemum segetum (corn marigold)) to or above the level of the clean crop”
Claim · model-written summary
In four experiments, nitrogen yield gains were greater in weedy than weed-free crops.
Not reportedTreatment
Verbatim
e0“n i four the yield increases were greater in the weedy than in the weed-free crop”
Claim · model-written summary
Doubling nitrogen did not raise weedy oat yield beyond the single rate in one experiment.
- Taxon
- oatsAvena sativae0
- Treatment
- doubling the amount of nitrogene0
- Outcome
- yield of oatse0
- Direction
- did not increasee0
- Comparator
- single ratee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In one experiment doubling the amount of nitrogen applied to the weedy crop did not increase the yield of oats more than the single rate”
Claim · model-written summary
Additional nitrogen failed to raise weedy crop yield in four other experiments.
Not reportedComparator
Verbatim
e0“In four other experiments additional nitrogen did not raise the yield of the weedy crop”
Claim · model-written summary
Nitrogen raised clean crop yield in only one of those four experiments.
- Taxon
- crope0
- Treatment
- nitrogenous manuringe0
- Outcome
- yield of the clean crope0
- Direction
- increasede0
- Qualifier
- only onee0
Not reportedComparator
Verbatim
e0“but in only one was the yield of the clean crop increased by nitrogenous manuring”
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See all 7 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.