Abstract
The effects of suppressing couch grass ( Elytrigia repens L.), through integrated management, on soil biological quality and N and P nutrition of barley ( Hordeum vulgare L.) were evaluated in a field experiment (1987–92) on a Dark Grey soil in Alberta, Canada. The management practices consisted of combinations of herbicide application, crop rotations and tillage treatments. The 3-year crop sequences consisted of continuous barley, canola ( Brassica rapa L.)–barley–barley, fallow–barley–barley, and barley or canola undersown with red clover ( Trifolium pratense L.)–red clover green manure–barley. In 1992, the sixth year of the experiment, soil and plant samples were analysed for nutrient content. Treatments that consisted of spring and autumn tillage only did not suppress couch grass and produced low barley yields and N and P uptake. More N was immobilized in couch grass shoots and rhizomes and soil microbial biomass with these treatments than with similar herbicide-treated crop rotations. Tillage-plus-herbicide treatments effectively suppressed couch grass and enabled the barley crop to compete for soil N, however, both spring and autumn tillage were required for weed control. The fallow treatment impaired soil quality by reducing soil and microbial C and N, but produced similar barley yields as continuous cropping with tillage-plus-chemical control. Red clover ploughed in for green manure enhanced soil quality indicators such as soil and microbial biomass C, total and mineralizable soil N, and microbial N, but did not increase barley yield compared to continuous grain cropping.
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Claims 11
Claim · model-written summary
Tillage only did not suppress couch grass.
- Taxon
- barley
.jpg?width=60)
Hordeum vulgaree0 - Treatment
- spring and autumn tillage onlye0
- Interactor
- couch grasse0weed
- Outcome
- couch grasse0
- Direction
- did not suppresse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Treatments that consisted of spring and autumn tillage only did not suppress couch grass and produced low barley yields and N and P uptake.”
Claim · model-written summary
Tillage only produced low barley yields.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- spring and autumn tillage onlye0
- Interactor
- couch grasse0weed
- Outcome
- barley yieldse0
- Direction
- lowe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments that consisted of spring and autumn tillage only did not suppress couch grass and produced low barley yields and N and P uptake.”
Claim · model-written summary
Tillage only produced low barley nitrogen and phosphorus uptake.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- spring and autumn tillage onlye0
- Interactor
- couch grasse0weed
- Outcome
- N and P uptakee0
- Direction
- lowe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments that consisted of spring and autumn tillage only did not suppress couch grass and produced low barley yields and N and P uptake.”
Claim · model-written summary
More nitrogen was immobilized in couch grass and microbial biomass under tillage only than under comparable herbicide rotations.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- these treatmentse0
- Interactor
- couch grasse0weed
- Outcome
- N was immobilized in couch grass shoots and rhizomes and soil microbial biomasse0
- Direction
- Moree0
- Comparator
- similar herbicide-treated crop rotationse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“More N was immobilized in couch grass shoots and rhizomes and soil microbial biomass with these treatments than with similar herbicide-treated crop rotations.”
e1“low barley yields and N and P uptake”
Claim · model-written summary
Tillage plus herbicide suppressed couch grass.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- Tillage-plus-herbicide treatmentse0
- Interactor
- couch grasse0weed
- Outcome
- couch grasse0
- Direction
- suppressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage-plus-herbicide treatments effectively suppressed couch grass and enabled the barley crop to compete for soil N”
Claim · model-written summary
Tillage plus herbicide enabled barley competition for soil nitrogen.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- Tillage-plus-herbicide treatmentse0
- Interactor
- couch grasse0weed
- Outcome
- barley crop to compete for soil Ne0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage-plus-herbicide treatments effectively suppressed couch grass and enabled the barley crop to compete for soil N”
Claim · model-written summary
Both spring and autumn tillage were required for weed control.
- Taxon
- barleyHordeum vulgaree1
- Interactor
- weede0weed
- Outcome
- both spring and autumn tillage were required for weed controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both spring and autumn tillage were required for weed control”
e1“barley crop”
Claim · model-written summary
Fallow reduced soil and microbial carbon and nitrogen.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- fallow treatmente0
- Outcome
- soil and microbial C and Ne0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The fallow treatment impaired soil quality by reducing soil and microbial C and N, but produced similar barley yields as continuous cropping with tillage-plus-chemical control.”
Claim · model-written summary
Fallow produced barley yields similar to continuous cropping with chemical control.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- fallow treatmente0
- Outcome
- barley yieldse0
- Direction
- similare0
- Comparator
- continuous cropping with tillage-plus-chemical controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The fallow treatment impaired soil quality by reducing soil and microbial C and N, but produced similar barley yields as continuous cropping with tillage-plus-chemical control.”
Claim · model-written summary
Red clover green manure enhanced soil quality indicators.
- Taxon
- barleyHordeum vulgaree1
- Treatment
- Red clover ploughed in for green manuree0
- Outcome
- soil quality indicators such as soil and microbial biomass C, total and mineralizable soil N, and microbial Ne0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Red clover ploughed in for green manure enhanced soil quality indicators such as soil and microbial biomass C, total and mineralizable soil N, and microbial N”
e1“did not increase barley yield compared to continuous grain cropping”
Claim · model-written summary
Red clover green manure did not increase barley yield compared with continuous grain cropping.
- Taxon
- barleyHordeum vulgaree0
- Treatment
- Red clover ploughed in for green manuree0
- Outcome
- barley yielde0
- Direction
- did not increasee0
- Comparator
- continuous grain croppinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Red clover ploughed in for green manure enhanced soil quality indicators such as soil and microbial biomass C, total and mineralizable soil N, and microbial N, but did not increase barley yield compared to continuous grain cropping.”
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