Field Crops Research 180 (2015) 29–36 Contents lists available at ScienceDirect Field Crops Research jou rn al hom epage: www.elsevier.com/locate/fcr Hill placement of manure and fertilizer micro-dosing improves yield and water use efﬁciency in the Sahelian low input millet-based cropping system Ali Ibrahim a,b,∗ , Robert Clement Abaidoo a,c , Dougbedji Fatondji b , Andrews Opoku a a Department of Crop and Soil Sciences, Kwame Nkrumah Univeristy of Science and Technology, Kumasi, South Ghana b International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), BP 12404, Niamey, Niger c International Institute of Tropical Agriculture, PMB 5320, Ibadan, Nigeria a r t i c l e i n f o Article history: Received 18 February 2015 Received in revised form 28 April 2015 Accepted 29 April 2015 Keywords: Millet Fertilizer micro-dosing Manure Hill-placement Yield Water use efﬁciency a b s t r a c t Inadequate nutrient supply and insufﬁcient rainfall are the most important limiting factors for crop pro- duction in the Sahelian agro-ecological zones. Targeted technology application may help to improve the efﬁcient use of limited nutrient and water resources. The objective of this study was to determine the optimal combination of fertilizer micro-dosing and manure application rates for improved millet yield and enhanced water use efﬁciency in low input millet-based cropping system. A two-year ﬁeld experiment was conducted at a research station in Niger using a randomized complete block design with three replications. The treatments consisted of the factorial combination of: (i) two fertilizer micro- dosing options (20 kg ha -1 of diammonium phosphate (DAP) and 60 kg ha -1 of NPK corresponding to 2 g hill -1 of DAP and 6 g hill -1 of NPK, respectively), (ii) cattle manure at four application rates (0 kg ha -1 , 1000 kg ha -1 , 2000 kg ha -1 , 3000 kg ha -1 ) and (iii) two methods of manure application (broadcasting and hill placement). Millet grain yields under fertilizer micro-dosing combined with manure was increased on average by 59%, 83% and 113% for 1000 kg ha -1 , 2000 kg ha -1 and 3000 kg ha -1 , respectively com- pared with fertilizer micro-dosing alone. Combined applications of manure and fertilizer micro-dosing increased water use efﬁciency signiﬁcantly. Hill placement of manure increased total dry matter on aver- age by 23% and water use efﬁciency by 35% relative to manure broadcasting. The total root length density was increased by 66% and 42% in hill placement of manure at 25 cm and 50 cm, respectively, from the hill centre compared with manure broadcast. These results indicate that millet production with the fertil- izer micro-dosing technology can be improved further by hill-placement of manure. The combination of 2000 kg ha -1 of manure and 20 kg DAP ha -1 hill-placed were most promising for increasing millet yield and the efﬁcient use of limited nutrients and water in Sahelian millet based systems. There is need for testing this technology further together with farmers to valuate its effectiveness. © 2015 Elsevier B.V. All rights reserved. 1. Introduction Pearl millet is the major food cereal cultivated in the Sahelian agro-ecological of Niger on coarser textured soils using up to 90% of the cropped area (Bationo et al., 1993). Even though this crop has a potential to adapt to harsh conditions, particularly low soil fertil- ity, its yield is often very low with an average of 400 kg ha -1 in low input smallholder millet farming systems (Sivakumar and Salaam, ∗ Corresponding author at: International Crops Research Institute for the Semi- Arid Tropics (ICRISAT) BP: 12404, Niamey, Niger. Tel.: +227 96 26 73 74; +233 267085456; fax: +227 20 73 43 29. E-mail addresses: ibramali@myway.com, ibabaye@gmail.com (A. Ibrahim). 1999). The inherent low soil fertility coupled together with inap- propriate soil fertility management and unreliable rainfall are main causes underlying the low millet productivity in the Sahelian zone of Niger (Graef and Haigis, 2001; Schlecht et al., 2006; Stoorvogel and Smaling, 1990). The use of mineral fertilizers by farmers in Niger remains very low and unattractive because of their high cost (Abdoulaye and Sanders, 2005; Bationo et al., 2003). To improve the efﬁcient use and to encourage smallholder farmers to increase the on-farm appli- cation of mineral fertilizer, the fertilizer micro-dosing technology developed by ICRISAT and partners has shown promising results in improving millet yields in the Sahel (Aune and Bationo, 2008; Tabo et al., 2007). This technology consists of the application of a small quantity of mineral fertilizer (one third of the recommended rate) http://dx.doi.org/10.1016/j.fcr.2015.04.022 0378-4290/© 2015 Elsevier B.V. All rights reserved.