Changing the Fertilizer Conversation in Nigeria: The Need for Site Specific Soil-Crop Fertilizer Use

KEY FINDINGS: -Landscape positions dictates fertilizer need. Distinct features in terms of slope, water holding capacity and inherent soil fertility determine the amount and type of fertilizer to be used (ICRISAT, 2017). This needs to be understood and appreciated by farmers, extension agents and those involved in the design and implementation of farmer productivity programs, particularly those involving fertilizer. -Soil rooting depth is critical. Having 10 -20 cm topsoil loss could decrease yield of corn even with added inorganic fertilizer. Complete total crop failure could occur (see figure 1) where, with increasing depth of soil loss, yields declined drastically even with added fertilizer at recommended rate for the area. -Limitations within a soil profile will reduce its effective rooting depth affecting anchorage, growth and development. (Agada 2018 unpublished Ph.D. Dissertation). -Rainfall characteristics such as high rainfall amounts, intensity and drop size will lead to loss of soil nutrients (weather added as organic or inorganic amendments) and loss of soil particles (Obi and Salako 1995; Agada et al, 2016) furthering the vicious cycle of erosion. Thus with varied environmental conditions across the country, real-time nutrient management strategies are necessary (Theriault et al, 2018). -There is an urgent need to educate farmers on fertilizer management practice. This involves information on fertilizer placement and timing, soil depth, soil types, slope positions and other agronomic/ management practices. With increased variation in climate, changing, or modifying hitherto farmer knowledge of certain agronomic practices in order to improve agricultural productivity is key (Delgado et al, 2011).