Efficient phosphorus application strategies for increased crop production in sub-Saharan West Africa

Abstract

Comparable data are lacking from the range of environments found in sub-Saharan West Africa to draw more general conclusions about the relative merits of locally available rockphosphate (RockP) in alleviating phosphorus (P) constraints to crop growth. To ®ll this gap, a multi-factorial ®eld experiment was conducted over 4 years at eight locations in Niger, Burkina Faso and Togo. These ranged in annual rainfall from 510 to 1300 mm. Crops grown were pearl millet (Pennisetum glaucum L.), sorghum (Sorghum bicolor (L.) Moench) and maize (Zea mays L.) either continuously or in rotation with cowpea (Vigna unguiculata Walp.) and groundnut (Arachis hypogaea L.). Crops were subjected to six P fertiliser treatments comprising RockP and soluble P at different rates and combined with 0 and 60 kg N ha À1 . For legumes, time trend analyses showed Pinduced total dry matter (TDM) increases between 28 and 72% only with groundnut. Similarly, rotation-induced raises in cereal TDM compared to cereal monoculture were only observed with groundnut. For cereals, at the same rate of application, RockP was comparable to single superphosphate (SSP) only at two millet sites with topsoil pH-KCl < 4:2 and annual average rainfall > 600 mm. Across the eight sites NPK placement at 0.4 g P per hill raised average cereal yields between 26 and 220%. This was con®rmed in 119 on-farm trials revealing P placement as a promising strategy to overcome P de®ciency as the regionally most growth limiting nutrient constraint to cereals.

Use of a warrantage system to face rural poverty and hunger in the semi-arid area of Burkina Faso

“…Daoudi and Wampfler (2010), Beaman et al (2014), Banerjee et al (2015) and Crépon et al (2015) showed that the agricultural credit promoted the adoption of innovations. This micro-credit strongly influences the attendance to inputs shops and therefore enables farmers to acquire fertilizer and other agricultural inputs (Buerkert et al, 2001;Tabo et al, 2011, Sogodogo et al, 2014.…”

“…With the objective to support poor small farmers, the warrantage system is a potential framework to inform and train costeffective agricultural innovations. This positive effect of the warrantage system on the accessibility to fertilizers and to efficient fertilizer management technologies, consequently improves crop yields (Buerkert et al, 2001;Bagayogo et al, 2011;Tabo et al, 2011). In fact, farmers involvement in the warrantage system increased significantly, their income because of the benefits linked to crop storage and the income-generating activities (FAO, 2012;Sogodogo et al, 2014).…”

“…Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License to soil phosphorus and nitrogen (Buerkert et al, 2001;Van Straaten, 2011). This systemic deficiency drastically limits crop growth and yield.…”

“…This technique not only makes inorganic fertilizers to be more affordable to poor small scale farmers but also increases the efficiency of their use (Buerkert et al, 2001;Bagayogo et al, 2011). The microdosing technique consists in applying small doses of fertilizers in the sowing hills during planting or 10 to 15 days after planting.…”

Effects of crop improvement technologies on downy mildew of pearl millet [Pennisetum glaucum (L.) R. Br.

“…Fertilizer micro-dosing on the other hand, involves the application of small amounts of mineral fertilizer (0.3 to 4 g) onto or close to the seed during planting (Tabo et al, 2006;Twomlow et al, 2010;Bagayoko et al, 2011;Aune and Ousman, 2011). This method was reported to increase crop yields at low cost (Aune and Bationo, 2008;Aune et al, 2007;Buerkert et al, 2001;Hayashi, 2008;Klaij et al, 1994;Aune and Ousman, 2011;Camara et al, 2013).…”