Abstract
The demand for home-grown cereals and fodder residues in Nigeria is increasing, but continuous cereal growing depletes soil fertility and artificial fertilisers are frequently uneconomic or unobtainable. An alternative is the use of leguminous crops that can be partly grazed and then ploughed into the soil to add nitrogen, organic matter and other minerals (green manuring). The effect of green manuring with pigeon pea (Cajanus cajan) on the growth and chemical composition of maize (Zea mays) was compared with that of high or low rates of N, P and K artificial fertiliser.
Green manuring increased soil organic carbon and total N content. One year of pigeon pea growth increased the maize leaf yield by a similar amount as the high level of fertiliser (125 kg N, 30 kg P and 30 kg K/ha) and produced a similar increase in leaf crude protein (CP) concentration.
It is concluded that green manuring with pigeon pea can provide crop nutrients equivalent to a high level of fertiliser application.