摘要
The crop production in Ethiopia is markedly constrained by soil nutrient depletion and limited fertilizer input. Nitrogen is among the most yield-limiting factors of cereal crops, especially in sub-Saharan Africa (SSA). A meta-analysis of 82 studies was carried out to evaluate the response of major cereal crops, viz. wheat, maize, barley, teff, and sorghum, to nitrogen fertilization in Ethiopia. The results showed that N-application significantly increased yields of all the five crops examined herein. The average yields of the treatment effects over controls for the five crops were 3775.8 kg∙ha<sup>−1</sup> and 2593.3 kg∙ha<sup>−1</sup>, respectively. The overall yield response to nitrogen treatments for all the crops was 64.8% (wheat, 96.5%;maize, 40.65%;barley 84.36%;teff, 50.48%;and sorghum;23%). Overall, nitrogen agronomic efficiency (AE<sub>N</sub>) and partial factor productivity (PFP<sub>N</sub>) were 18.2 and 71.81 kg∙kg<sup>−1</sup>, respectively. A downtrend of nitrogen use efficiency with an increase in N rate was realized. The yield response was higher for the nitrogen treatment effects of >100 kg∙N∙ha<sup>−1</sup> (123.9%), clay soils (75.46%), low initial soil organic carbon (SOC) and available phosphorous (AP) (92.4% and 101.6%), respectively, Therefore, we recommend the application of nitrogen fertilizer (>100 kg∙N∙ha<sup>−1</sup>), especially on infertile soils for improved grain yield and NUE in aforementioned cereal crops in Ethiopia and similar regions in sub-Saharan Africa (SSA).
The crop production in Ethiopia is markedly constrained by soil nutrient depletion and limited fertilizer input. Nitrogen is among the most yield-limiting factors of cereal crops, especially in sub-Saharan Africa (SSA). A meta-analysis of 82 studies was carried out to evaluate the response of major cereal crops, viz. wheat, maize, barley, teff, and sorghum, to nitrogen fertilization in Ethiopia. The results showed that N-application significantly increased yields of all the five crops examined herein. The average yields of the treatment effects over controls for the five crops were 3775.8 kg∙ha<sup>−1</sup> and 2593.3 kg∙ha<sup>−1</sup>, respectively. The overall yield response to nitrogen treatments for all the crops was 64.8% (wheat, 96.5%;maize, 40.65%;barley 84.36%;teff, 50.48%;and sorghum;23%). Overall, nitrogen agronomic efficiency (AE<sub>N</sub>) and partial factor productivity (PFP<sub>N</sub>) were 18.2 and 71.81 kg∙kg<sup>−1</sup>, respectively. A downtrend of nitrogen use efficiency with an increase in N rate was realized. The yield response was higher for the nitrogen treatment effects of >100 kg∙N∙ha<sup>−1</sup> (123.9%), clay soils (75.46%), low initial soil organic carbon (SOC) and available phosphorous (AP) (92.4% and 101.6%), respectively, Therefore, we recommend the application of nitrogen fertilizer (>100 kg∙N∙ha<sup>−1</sup>), especially on infertile soils for improved grain yield and NUE in aforementioned cereal crops in Ethiopia and similar regions in sub-Saharan Africa (SSA).
作者
Solomon Yokamo
Xiaoqiang Jiao
Kanomanyanga Jasper
Fekadu Gurmu
Mohammad Shah Jahan
Rongfeng Jiang
Solomon Yokamo;Xiaoqiang Jiao;Kanomanyanga Jasper;Fekadu Gurmu;Mohammad Shah Jahan;Rongfeng Jiang(College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing, China;Southern Agricultural Research Institute (SARI), Hawassa 06, Ethiopia;Ethiopian Agricultural Research Council Secretariat (EARCS), Addis Ababa, Ethiopia;Key Laboratory of Southern Vegetable Crop Genetic Improvement in Ministry of Agriculture, College of Horticulture, Nanjing Agricultural University, Nanjing, China;Department of Horticulture, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh)
