Table 4: Estimated costs of production, gross revenue, and returns on investment of (a) various crop sequences (b) maize grown after the sequences with N application to the maize and (c) maize grown after the sequences without N application to the maize.

Crop sequence  Economic yield (kg ha−1) Total revenue  (US$) ha−1 Cost of production (US$) ha−1 Total cost  Net revenue  Return on investment Land Input Labour (a) Crops in the sequence                  1Cassava 31,000 2545.1 41.7 41.7 635.0 718.4 1826.7 254  2Pigeonpea 1,870 623.3 41.7 8.3 221.5 271.5 351.8 130  3Mucuna-maize-mucuna 2,016 365.1 41.7 41.7 247.4 330.8 34.3 10  4Cowpea-maize-cowpea 2,536* (1,230) 1079.0 41.7 106,1 475.1 622.9 456.1 73  5Maize-maize-maize 3,287 595.2 41.7 36.1 386.1 463.8 456.1 28  6Speargrass fallow 0 0 41.7 0 0 41.7 −41.7 −100 (b) Maize after crop sequence with N application                  CS 1 2,738 495.9 13.9 104.2 190.2 308.3 187.6 61  CS 2 2,974 538.5 13.9 104.2 196.5 314.6 223.9 71  CS 3 4,194 759.4 13.9 104.2 245.9 364.0 395.4 108  CS 4 2,331 422.1 13.9 104.2 177.0 295.1 127.0 43  CS 5 2,126 385.0 13.9 104.2 175.4 293.5 91.4 31  CS 6 2,848 515.7 13.9 104.2 224.4 342.5 173.3 51 (c) Maize after crop sequence without N application                  CS 1 3,000 543.2 13.9 13.9 175.6 203.4 339.8 167  CS 2 2,423 438.8 13.9 13.9 165.5 193.3 245.5 127  CS 3 2,961 537.7 13.9 13.9 209.7 237.5 300.2 126  CS 4 1,772 302.8 13.9 13.9 155.2 183.0 119.8 66  CS 5 1,380 249.9 13.9 13.9 153.0 180.7 69.1 38  CS 6 1,048 189.8 13.9 13.9 173.7 200.9 −11.1 −6

1US$82.1 . 2US$333.3 . 3US$181.1 for maize. 4US$337.5 for cowpea and US$181.1 for maize. 5US$181.1 for maize. 6US$0. *Yield of maize (figure in brackets). CS 1: cassava; CS 2: Pigeonpea; CS 3: Mucuna-maize-mucuna; CS 4: Cowpea-maize-cowpea; CS 5: Maize-maize-maize; CS 6: Speargrass fallow. Source: [9].