Abstract
Abstract Field trials were conducted for three years on the response of maize to nitrogen (N), phosphorus (P), and potassium (K) fertilizers on Oyo Soil Series (Arenic Haplustalf) and Iregun series (Aquic Haplustalf) in the derived savanna and southern guinea savanna zones of Nigeria, respectively. Nitrogen fertilizer as granulated urea at rates 0–300 kg N/ha, P fertilizer as single superphosphate at rates 0–120 kg P/h, and K fertilizer as muriate of potash at rates 0–180 kg K/ha were used for the different nutrient combinations. The base rates for N, P, and K were 100 kg N/ha, 40 kg P/ha, and 60 kg K/ha, respectively. The results of the trials showed that annual application of the blanket recommended N, P, and K rates to maize grown under intensive land use system could not produce optimum yield. Fertilizer efficiency varied along with soil test values from year to year. The highest response by maize in these zones was to N, the optimum rate ranged from 50–100 kg N/ha. Application of high rates of P and K fertilizers on soils with fairly sufficient nutrient level showed no significant effect on maize yield. But when P and K were applied at low rates (20 kg P/ha and 30 kg K/ha), their contents in the leaf and maize yield, in most cases, increased significantly. The results, however, showed that N, P, and K recommendations for optimum maize yield in both zones are 50–100 kg N/ha, 20 kg P/ha, and 0–30 kg K/ha, respectively.
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Claims 12
Claim · model-written summary
Annual blanket N, P and K rates did not produce optimum maize yield under intensive land use.
- Treatment
- blanket recommended N, P, and K ratese0
- Outcome
- optimum yielde0
- Direction
- could not producee0
- Qualifier
- under intensive land use systeme0
Zea maysNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“annual application of the blanket recommended N, P, and K rates to maize grown under intensive land use system could not produce optimum yield.”
Claim · model-written summary
Fertilizer efficiency varied with soil test values between years.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fertilizer efficiency varied along with soil test values from year to year.”
t0“maize”
Claim · model-written summary
Maize responded most strongly to nitrogen, with an optimum rate of 50–100 kg N/ha.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The highest response by maize in these zones was to N, the optimum rate ranged from 50–100 kg N/ha.”
Claim · model-written summary
High P fertilizer rates had no significant effect on maize yield in soils with sufficient nutrients.
- Treatment
- high rates of Pe0
- Outcome
- maize yielde0
- Direction
- no significant effecte0
- Qualifier
- soils with fairly sufficient nutrient levele0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of high rates of P and K fertilizers on soils with fairly sufficient nutrient level showed no significant effect on maize yield.”
Claim · model-written summary
High K fertilizer rates had no significant effect on maize yield in soils with sufficient nutrients.
- Treatment
- K fertilizerse0
- Outcome
- maize yielde0
- Direction
- no significant effecte0
- Qualifier
- soils with fairly sufficient nutrient levele0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of high rates of P and K fertilizers on soils with fairly sufficient nutrient level showed no significant effect on maize yield.”
Claim · model-written summary
Low P application significantly increased maize leaf P content in most cases.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when P and K were applied at low rates (20 kg P/ha and 30 kg K/ha), their contents in the leaf and maize yield, in most cases, increased significantly.”
t0“maize”
Claim · model-written summary
Low K application significantly increased maize leaf K content in most cases.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when P and K were applied at low rates (20 kg P/ha and 30 kg K/ha), their contents in the leaf and maize yield, in most cases, increased significantly.”
t0“maize”
Claim · model-written summary
Low P application significantly increased maize yield in most cases.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when P and K were applied at low rates (20 kg P/ha and 30 kg K/ha), their contents in the leaf and maize yield, in most cases, increased significantly.”
t0“maize”
Claim · model-written summary
Low K application significantly increased maize yield in most cases.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when P and K were applied at low rates (20 kg P/ha and 30 kg K/ha), their contents in the leaf and maize yield, in most cases, increased significantly.”
t0“maize”
Claim · model-written summary
The authors recommend 50–100 kg N/ha for optimum maize yield in both zones.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N, P, and K recommendations for optimum maize yield in both zones are 50–100 kg N/ha, 20 kg P/ha, and 0–30 kg K/ha, respectively.”
t0“maize”
Claim · model-written summary
The authors recommend 20 kg P/ha for optimum maize yield in both zones.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N, P, and K recommendations for optimum maize yield in both zones are 50–100 kg N/ha, 20 kg P/ha, and 0–30 kg K/ha, respectively.”
t0“maize”
Claim · model-written summary
The authors recommend 0–30 kg K/ha for optimum maize yield in both zones.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N, P, and K recommendations for optimum maize yield in both zones are 50–100 kg N/ha, 20 kg P/ha, and 0–30 kg K/ha, respectively.”
t0“maize”
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