Premium
Fertilizer Use Efficiency and Profitability of Irrigated Rice in Mali and Niger
Author(s) -
Garba Maman,
Dicko Mohamed,
Kamissoko Nianankoro,
Maman Nouri,
Wortmann Charles
Publication year - 2018
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.2134/agronj2017.09.0512
Subject(s) - fertilizer , agronomy , nutrient , oryza sativa , mathematics , irrigation , environmental science , biology , ecology , biochemistry , gene
Nutrient response functions for irrigated rice in the Sahel were determined. Yield response of irrigated rice to applied N and P has good profit potential. Response to micronutrients occurred in Mali but not in Niger. The response functions can be used in fertilizer use optimization decision tools.Rice ( Oryza sativa L. and O. glaerrima Steud.) is an important food crop in Africa. Maximizing profitability of fertilizer use requires determination of nutrient response functions. Five trials were conducted in the Niger River valley of Mali and Niger. The objectives included determination of nutrient response functions for irrigated rice, other nutrient deficiencies, and profitability of fertilizer use. Average trial grain yields were 3.07, 4.09 and 5.49 Mg ha −1 in Niger and on Danga and Moursi soil types in Mali, respectively. Nitrogen response was curvilinear to plateau in all cases except for a linear response for Danga soil in Mali. Yield increases with 150 kg ha −1 N ranged from 0.7 to 1.7 Mg ha −1 . Responses to P were curvilinear with grain yield increases of approximately 0.3 and 1.7 Mg ha −1 in Niger and Mali, respectively, with 30 kg ha −1 P. The economically optimal rate (EOR) for N when fertilizer use cost was 4.5 times the value of rice grain (kg kg −1 ) ranged from 62 to >150 kg ha −1 . The EOR of P ranged from 27 to 33 kg ha −1 in Mali and from 12 to 16 kg ha −1 in Niger, depending on the relative cost of fertilizer P. Agronomic efficiency of N varied from <10 to 20 kg kg −1 , and of P with 10 kg ha −1 P from 49 to 95 kg kg −1 , depending on location. Net returns to N and P use exceeded 100%. This information is applicable in nutrient management decision tools oriented to farmer profitability in Mali and Niger.