Abstract
Abstract The integrated use of legume green manure or legume residue with inorganic N fertilizer could offer rice ( Oryza sativa L.) farmers an opportunity to reduce their expensive inorganic fertilizer inputs. A 2‐yr field experiment was conducted on an Andaqueptic Haplaquoll in the Philippines to determine the effect of cowpea [ Vigna unguiculata (L.) Walp.] cropping systems on response of a subsequent rice crop to applied urea and effectiveness of several urea management practices for rice. The pre‐rice cropping systems including fallow, cowpea incorporated at the flowering stage as a green manure, and cowpea grown to maturity with either grain and pods removed or all aboveground vegetation removed prior to soil puddling for rice. The mean aboveground N content was 66 kg N ha −1 for green manure and 54 kg N ha −1 for mature cowpea without grain and pods. Rice yield responses following fallow and cowpea cropping with removal of all aboveground cowpea vegetation were similar, but mean rice grain yields were 0.9 and 0.7 Mg ha −1 higher following incorporation of green manure and residue, respectively. The green manure substituted for 34 and 54 kg urea‐N ha −1 in 1986 and 1987, respectively. Residue substituted for 44 and 50 kg urea‐N ha − 1 in 1986 and 1987, respectively. Early application of urea (two‐thirds basal and one‐third at 5 d before panicle initiation) was superior to delayed application (one‐half at 14 d after transplanting and one‐half at 10 d after panicle initiation), even when supplemental N as green manure or residue was incorporated 15 d before transplanting. Cowpea grown for green manure or for grain, with incorporation of residues remaining after harvest, made similar positive contributions to rice yield, but growing cowpea to maturity offered the advantage of attaining approximately 1.0 Mg ha −1 cowpea grain production.
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Claims 12
Claim · model-written summary
Green manure cowpea contained 66 kg N ha −1 aboveground.
- Taxon
- cowpea
Vigna unguiculatae0 - Outcome
- aboveground N contente0
- Value
- 66 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The mean aboveground N content was 66 kg N ha −1 for green manure and 54 kg N ha −1 for mature cowpea”
Claim · model-written summary
Mature cowpea without grain and pods contained 54 kg N ha −1 aboveground.
- Taxon
- cowpeaVigna unguiculatae0
- Outcome
- 54 kg N ha −1e0
- Value
- 54 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“54 kg N ha −1 for mature cowpea without grain and pods”
Claim · model-written summary
Rice grain yield was similar after fallow and cowpea cropping with removal of all aboveground vegetation.
- Taxon
- Rice
Oryza sativae0 - Treatment
- cowpea cropping with removal of all aboveground cowpea vegetatione0
- Outcome
- Rice yield responsese0
- Direction
- similare0
- Comparator
- fallowe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Rice yield responses following fallow and cowpea cropping with removal of all aboveground cowpea vegetation were similar”
Claim · model-written summary
Green manure incorporation increased mean rice grain yield by 0.9 Mg ha −1.
- Taxon
- riceOryza sativae0
- Treatment
- incorporation of green manuree0
- Outcome
- rice grain yieldse0
- Direction
- highere0
- Value
- 0.9e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“mean rice grain yields were 0.9 and 0.7 Mg ha −1 higher following incorporation of green manure and residue, respectively”
Claim · model-written summary
Residue incorporation increased mean rice grain yield by 0.7 Mg ha −1.
- Taxon
- riceOryza sativae0
- Treatment
- residuee0
- Outcome
- rice grain yieldse0
- Direction
- highere0
- Value
- 0.7 Mg ha −1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“mean rice grain yields were 0.9 and 0.7 Mg ha −1 higher following incorporation of green manure and residue, respectively”
Claim · model-written summary
Green manure substituted for 34 kg urea‐N ha −1 in 1986.
Not reportedTaxon
Verbatim
e0“The green manure substituted for 34 and 54 kg urea‐N ha −1 in 1986 and 1987, respectively”
Claim · model-written summary
Green manure substituted for 54 kg urea‐N ha −1 in 1987.
Not reportedTaxon
Verbatim
e0“The green manure substituted for 34 and 54 kg urea‐N ha −1 in 1986 and 1987, respectively”
Claim · model-written summary
Cowpea residue substituted for 44 kg urea‐N ha −1 in 1986.
Not reportedTaxon
Verbatim
e0“Residue substituted for 44 and 50 kg urea‐N ha − 1 in 1986 and 1987, respectively”
Claim · model-written summary
Cowpea residue substituted for 50 kg urea‐N ha −1 in 1987.
Not reportedTaxon
Verbatim
e0“Residue substituted for 44 and 50 kg urea‐N ha − 1 in 1986 and 1987, respectively”
Claim · model-written summary
Early urea application was superior to delayed application despite incorporated green manure or residue.
- Treatment
- Early application of ureae0
- Outcome
- superiore0
- Direction
- superiore0
- Qualifier
- even when supplemental N as green manure or residue was incorporated 15 d before transplantinge0
- Comparator
- delayed applicatione0
Not reportedTaxon
Verbatim
e0“Early application of urea (two‐thirds basal and one‐third at 5 d before panicle initiation) was superior to delayed application (one‐half at 14 d after transplanting and one‐half at 10 d after panicle initiation), even when supplemental N as green manure or residue was incorporated 15 d before transplanting”
Claim · model-written summary
Green manure and grain cropping with residue incorporation made similar positive contributions to rice yield.
- Taxon
- riceOryza sativae0
- Treatment
- Cowpea grown for green manuree0
- Outcome
- rice yielde0
- Direction
- similare0
- Comparator
- for grain, with incorporation of residues remaining after harveste0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cowpea grown for green manure or for grain, with incorporation of residues remaining after harvest, made similar positive contributions to rice yield”
Claim · model-written summary
Mature cowpea cropping produced approximately 1.0 Mg ha −1 grain.
- Taxon
- cowpeaVigna unguiculatae0
- Outcome
- cowpea grain productione0
- Value
- approximately 1.0 Mg ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“growing cowpea to maturity offered the advantage of attaining approximately 1.0 Mg ha −1 cowpea grain production”
The same questions in other papers
Vigna unguiculata · yield · Oryza sativa (rice)Positive and negative results
49 papers in the same direction as this paper · 2 in the opposite direction · 1 reporting no difference from an alternative
- negative
- negative
- no effect
49 papers more in this group
See all 53 papers →fertilization · yield · Oryza sativa (rice)Positive and negative results
3,182 papers in the same direction as this paper · 207 in the opposite direction · 65 reporting no difference from an alternative
- positive
- positive
- positive
3,451 papers more in this group
See all 3,455 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.