Effect of N-enriched co-compost on transpiration efﬁciency and water-use efﬁciency of maize (Zea mays L.) under controlled irrigation Noah Adamtey a, *, Olufunke Coﬁe a,1 , K.G. Ofosu-Budu b,2 , J. Ofosu-Anim c,3 , K.B. Laryea d,4 , Dionys Forster e,5 a International Water Management Institute (IWMI), West African Ofﬁce, PMB CT 112 Cantonments, Accra, Ghana b Institute of Agric. Research, Agric. Research Centre, Kade Campus, College of Agricultural and Consumer Sciences, University of Ghana, Legon, Ghana c Department of Crop Science, College of Agricultural and Consumer Science, University of Ghana, Legon, Ghana d Department of Soil Science, College of Agricultural and Consumer Science, University of Ghana, P.O. Box LG 245, Legon, Ghana e Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Water and Sanitation in Developing Countries (Sandec), P.O. Box 611, Ueberlandstrasse 133, CH-8600 Du ¨bendorf, Switzerland Agricultural Water Management xxx (2010) xxx–xxx ARTICLE INFO Article history: Received 20 April 2009 Received in revised form 2 February 2010 Accepted 7 February 2010 Available online xxx Keywords: Crop water use Water consumption rate Transpiration rate Transpiration efﬁciency Water-use efﬁciency ABSTRACT Population growth, urban expansion and economic development are increasing competition for water use between agriculture and other users. In addition, the high rate of soil degradation and declining soil moisture in the Sub-Saharan African Region have called for several crop production management and irrigation options to improve soil fertility, reduce water use by crops and produce ‘more crops per drop of water’. Notwithstanding this, considerable variations exist in the literature on water-use efﬁciency, WUE cwu (economic yield per water used) for maize (Zea mays L.) across climates and soil management practices. Different views have been expressed on the effect of different rates of nitrogen (N) application on transpiration efﬁciency, TE (biomass produced per unit of water transpired). The objectives of the study were to assess the effect of different rates of N-enriched municipal waste co-compost and its derivatives on TE, WUE cwu and yield of maize (Z. mays L.) in comparison to inorganic fertiliser. The greenhouse pot experiment was conducted in Accra, Ghana on a sandy loam soil (Ferric Lixisol) using a split plot design. The main plot treatments were soil (S), dewatered faecal sludge (DFS), municipal solid waste compost (C), co-compost from municipal solid waste and dewatered faecal sludge (Co), compost enriched with (NH 4 ) 2 SO 4 (EC), co-compost enriched with (NH 4 ) 2 SO 4 (ECO), (NH 4 ) 2 SO 4 and NPK15–15–15 + (NH 4 ) 2 SO 4 . The sub-plot treatments were different rates of application of nitrogen fertiliser applied at the rate of 91, 150 and 210 kg N ha 1 respectively. Maize cv. Abelehii was grown in a poly bag ﬁlled with 15 kg soil. Eight plants per treatment were selected randomly and used for the collection of data on growth parameters forth-nightly. At physiological maturity two plants per treatment were also selected randomly from each treatment plot for yield data. The results showed that TE of maize (Z. mays) varied for the different treatments and these are 6.9 Pa in soil (S) alone to 8.6 Pa in ECO. Increase in N application rate increased TE at the vegetative phase for fast nutrient releasing fertilisers (DFS, ECO, EC, NPK + (NH 4 ) 2 SO 4 , (NH 4 ) 2 SO 4 ) and at the reproductive phase for slow nutrient releasing fertilisers (C and CO). Water-use efﬁciency increased signiﬁcantly as rate of N application increased. Treatment ECO improved crop WUE cwu and was 11% and 4 times higher than that for NPK + (NH 4 ) 2 SO 4 or soil alone; and 18– 36% higher than those for DFS and CO. Treatment ECO used less amount of water to produce dry matter yield (DMY) and grain yield (GY) that was 5.2% and 12.6%, respectively, higher than NPK + (NH 4 ) 2 SO 4 . Similarly, the DMY and GY for ECO was 8.9–18.5% and 23.4–34.7%, respectively, higher than DFS and CO. High nutrient (N and K) uptake, TE, and low leaf senescence accounts for 83% of the variations in DMY whereas WUE cwu accounts for 99% of the variations in GY. Thus, the study concluded that different sources of fertiliser increased TE and WUE cwu of maize differently as N application rate increases. ß 2010 Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +233 24 35 32 18 1; fax: +233 21 78 47 52. E-mail addresses: nadamtey@yahoo.co.uk (N. Adamtey), o.coﬁe@cgiar.org (O. Coﬁe), o_budu@yahoo.com (K.G. Ofosu-Budu), aweze@ug.edu.gh (J. Ofosu-Anim), blaryea@ug.edu.gh (K.B. Laryea), dionys.forster@eawag.ch (D. Forster). 1 Tel.: +233 21 78 47 53; fax: +233 21 78 47 52. 2 Tel.: +233 24 44 28 19 9. 3 Tel.: +233 24 47 17 62 1. 4 Tel. +233 27 74 00 24 3. 5 Tel.: +41 44 82 35 28 6; fax: +41 44 82 35 39 9. G Model AGWAT-2979; No. of Pages 11 Please cite this article in press as: Adamtey, N., et al., Effect of N-enriched co-compost on transpiration efﬁciency and water-use efﬁciency of maize (Zea mays L.) under controlled irrigation. Agric. Water Manage. (2010), doi:10.1016/j.agwat.2010.02.004 Contents lists available at ScienceDirect Agricultural Water Management journal homepage: www.elsevier.com/locate/agwat 0378-3774/$ – see front matter ß 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.agwat.2010.02.004