Alleviating soil fertility constraints to increased crop production in West Africa: The experience in the Sahel

Abstract

Lack of moisture limits crop production in semi-arid west Africa but poor soil fertility is a more serious constraint in the long run. Work done by IFDC and ICRISAT showed that phosphorus is the most limiting nutrient although response by millet to nitrogen when moisture and P are non-limiting can be substantial. A summary of the results of field trials in Niger showed that the sufficiency level for P estimated by regression analysis on the basis of Bray 1 extractable P is 7.9 JAg Pig of soil for 90% of maximum yield of millet. Application of 15-20 kg P/ha was usually adequate for optimum yields. Matam phosphate rock (PR) from Senegal, Tilemsi PR from Mali and Tahoua PR from Niger which are medium reactive were found to be suitable for direct application while partial acidulation (50% with sulfuric acid) of the less reactive phosphate rocks resulted in products with similar agronomic effectiveness as commercial superphosphates. Tests conducted by farmers showed that millet yields can be increased by more than 250% by the use of fertilizers. The need for constant monitoring of the crop needs for sulfur and potassium under continuous cultivation was highlighted.

Crop Upgrading Strategies and Modelling for Rainfed Cereals in a Semi-Arid Climate—A Review

“…Several authors have reported a challenge of poor soil fertility that farmers in semi-arid areas are facing [153][154][155]. The problem is acute for poor farmers in semi-arid Sub-Saharan Africa countries [151,156,157]. The precision-farming technique referred to as "microdosing" has been developed by experts [158][159][160].…”

Desertification and a new countermeasure in the Sahel, West Africa

“…Because of this, cultivation causes decrease in soil nutrients. Detailed studies on this chemical degradation of the soil (depletion of soil nutrients) and its recovery through fertilization have been conducted by A. Bationo, A. Buerkert, K. Hayashi and others (see Bationo and Mokwunye 1991;Bationo et al 1993;Buerkert et al 2000;Hayashi et al 2008;etc.). Additionally, Nakamura et al (2010) have published work on the depletion of soil organic matter as a result of cultivation and its recovery through the application of organic amendment.…”

Evaluation of the Indigenous Use of the Weed Sida cordifolia L. in the Sahelian Zone of West Africa

“…As local farmers in Niger have limited access to outsourcing for soil fertility management 4,32 , judicious utilization of their finite resources is crucial. Precision agriculture is one way to use limited resources efficiently through minimal inputs for maximal outputs from crop production 11,29 .…”