The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has been promoting microdosing in Mali, Burkina Faso, and Niger (see Script 79.4 below). ICRISAT defines microdosing as “the application of small, affordable quantities of fertilizer with the seed at planting time or as top dressing 3 to 4 weeks after emergence.” This process is very precise. It is in contrast to spreading chemical fertilizer across entire fields. Many farmers cannot afford to buy chemical fertilizer in the amount recommended by researchers, so this technique enables them to make the most of the amount of fertilizer that they are able to access. ICRISAT has focused research on microdosing with chemical fertilizers – farmers could also test this practice using compost.
In West Africa, farmers found a labour-saving method for microdosing. While one farmer walks through the field making planting holes, a second follows him or her with two vessels: one with the seed and the other with fertilizer. The second farmer plants the seed, adds a three-finger pinch of fertilizer, and pushes the soil over the hole with his feet.
Farmers’ experiences and recent research have shown that, when carefully applied, small doses of inorganic/chemical fertilizer can have a strongly positive effect on crop yields. Together with extensive use of organic materials and efforts to conserve soil and water, inorganic fertilizer in small amounts can be a useful input.
For more information from ICRISAT visit:
Here is a full case study from ICRISAT, as a pdf file: http://www.icrisat.org/impacts/impact-stories/icrisat-is-fertilizer-microdosing.pdf
Farm Radio International has produced a number of scripts on different fertilization techniques. Browse our archive at: http://www.farmradio.org/english/radio-scripts/fertilization.asp
This issue pack on soil health also contains a lot of background information on how to get the best from your soil:
Here is one script which presents micro-dosing in detail:
Micro-doses of Fertilizer Increase Yields in the Sahel (Package 79, Script 4, November 2006) http://www.farmradio.org/english/radio-scripts/79-4script_en.asp
While most farmers who have tried microdosing are in West Africa, this simple technique could be used in any region. Visit your local agricultural research station to see if they have done any work on this, or know of anyone who uses the technique.
You could introduce the technique to farmers and get their opinions: Is it cost effective? Will it be difficult to implement? Will it mean a lot of extra work? Which other fertilization methods would they prefer to use? Which other fertilization methods do they currently use? Would these methods work alongside each other? Would microdosing with compost work? Has anyone tried this?