Abstract
Cowpea (Vigna unguiculata (L.) Walp) is important in semi-arid West Africa. Yields are low due to inadequate water and nutrient availability and other constraints. Grain and fodder yield responses to nutrient application were determined from 21 site-years of research conducted in the Sahel and Sudan Savanna. The incomplete factorial treatment arrangement varied by country but included: Four levels each of P and K in 7.5 and 10.0 kg ha-1 increments, respectively; Mg-S-Zn-B package (Mg-S-Zn-B); and comparable with and without manure treatments. Yield increases due to P application always occurred with curvilinear to plateau or linear responses. The overall mean grain yield increase was 0.35 Mg ha-1 and 47% due to application of 22.5 kg ha-1 P. Application of K resulted in a linear negative effect in 2014 and positive effect in 2015 for on-station trials in Niger, but had no effect in Burkina Faso and for on-farm trials in Niger. Yield was not affected by Mg-S-Zn-B in Burkina Faso but was increased by a mean of 0.085 Mg ha-1 in Niger. Manure application resulted in a mean yield increase of 0.1 Mg ha-1 in Niger but only with fertilizer P applied, and had no effect in Burkina Faso. Cowpea grain and fodder yields were responsive to fertilizer P up to 22.5 kg ha-1 but little affected by other applied nutrients. Key words: Fertilizer, fodder, grain, manure, micronutrient, phosphorus, secondary nutrient, Sahel, Sudan Savanna.
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Claims 10
Claim · model-written summary
Phosphorus application increased yield with curvilinear to plateau or linear responses.
- Taxon
- Cowpea
Vigna unguiculatae1 - Treatment
- P applicatione0
- Outcome
- Yielde0
- Direction
- increasese0
- Qualifier
- curvilinear to plateau or linear responsese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield increases due to P application always occurred with curvilinear to plateau or linear responses”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Applying 22.5 kg per hectare phosphorus increased overall mean grain yield by 0.35 Mg per hectare and 47%.
- Taxon
- CowpeaVigna unguiculatae1
- Treatment
- application of 22.5 kg ha-1 Pe0
- Outcome
- grain yielde0
- Direction
- increasee0
- Value
- 0.35 Mg ha-1 and 47%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The overall mean grain yield increase was 0.35 Mg ha-1 and 47% due to application of 22.5 kg ha-1 P”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Potassium application had a linear negative yield effect in 2014 on station in Niger.
- Taxon
- CowpeaVigna unguiculatae1
- Treatment
- Application of Ke0
- Outcome
- effecte0
- Direction
- negativee0
- Qualifier
- 2014e0
- Setting
- Nigere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of K resulted in a linear negative effect in 2014 and positive effect in 2015 for on-station trials in Niger”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Potassium application had a positive yield effect in 2015 on station in Niger.
- Taxon
- CowpeaVigna unguiculatae1
- Treatment
- Application of Ke0
- Outcome
- effecte0
- Direction
- positivee0
- Qualifier
- 2015e0
- Setting
- Nigere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of K resulted in a linear negative effect in 2014 and positive effect in 2015 for on-station trials in Niger”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Potassium application had no yield effect in Burkina Faso and in on farm trials in Niger.
- Taxon
- CowpeaVigna unguiculatae3
- Treatment
- Application of Ke1
- Outcome
- Yielde2
- Direction
- no effecte0
- Setting
- Burkina Faso and for on-farm trials in Nigere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“had no effect in Burkina Faso and for on-farm trials in Niger”
e1“Application of K”
e2“Yield was not affected by Mg-S-Zn-B in Burkina Faso”
e3“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Mg-S-Zn-B did not affect yield in Burkina Faso.
- Taxon
- CowpeaVigna unguiculatae1
- Treatment
- Mg-S-Zn-Be0
- Outcome
- Yielde0
- Direction
- not affectede0
- Setting
- Burkina Fasoe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield was not affected by Mg-S-Zn-B in Burkina Faso”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Mg-S-Zn-B increased yield by a mean of 0.085 Mg per hectare in Niger.
- Taxon
- CowpeaVigna unguiculatae3
- Treatment
- Mg-S-Zn-Be1
- Outcome
- Yielde2
- Direction
- increasede0
- Value
- 0.085 Mg ha-1e0
- Setting
- Nigere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“was increased by a mean of 0.085 Mg ha-1 in Niger”
e1“Yield was not affected by Mg-S-Zn-B in Burkina Faso”
e2“Yield was not affected by Mg-S-Zn-B in Burkina Faso”
e3“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Manure increased yield by a mean of 0.1 Mg per hectare in Niger when fertilizer phosphorus was applied.
- Taxon
- CowpeaVigna unguiculatae1
- Treatment
- Manure applicatione0
- Outcome
- yielde0
- Direction
- increasee0
- Value
- 0.1 Mg ha-1e0
- Qualifier
- only with fertilizer P appliede0
- Setting
- Nigere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Manure application resulted in a mean yield increase of 0.1 Mg ha-1 in Niger but only with fertilizer P applied”
e1“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Manure did not affect yield in Burkina Faso.
- Taxon
- CowpeaVigna unguiculatae3
- Treatment
- Manure applicatione1
- Outcome
- yielde2
- Direction
- no effecte0
- Setting
- Burkina Fasoe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“and had no effect in Burkina Faso”
e1“Manure application”
e2“mean yield increase of 0.1 Mg ha-1”
e3“Cowpea (Vigna unguiculata (L.) Walp)”
Claim · model-written summary
Cowpea grain and fodder yields responded to fertilizer phosphorus up to 22.5 kg per hectare.
- Taxon
- CowpeaVigna unguiculatae0
- Treatment
- fertilizer P up to 22.5 kg ha-1e0
- Outcome
- grain and fodder yieldse0
- Direction
- responsivee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cowpea grain and fodder yields were responsive to fertilizer P up to 22.5 kg ha-1”
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