Improved fallow with pigeon pea for soil fertility improvement and to increase maize production in a smallholder crop-livestock farming system in the subhumid zone of Ghana

Abstract

Pigeon pea is cultivated by most smallholder crop-livestock farmers mainly as a border crop. It is quite often sparsely intercropped in cereal-based cropping systems in the subhumid zone of Ghana. Management of pigeon pea and its biomass is a promising means of improving many abandoned arable fields but has not been consciously undertaken. The objective of this trial was to explore the use of pigeon pea and the management of its pruned biomass as part of an improved fallow for crop-livestock farming. Three pigeon-pea management options and a natural fallow (two-year fallow period) were compared in terms of maize grain yield and changes in soil organic carbon, total nitrogen and cation exchange capacity. Pigeon pea grain yield ranged between 615 and 678 kg ha-1 and 527 and 573 kg ha-1 in the first and second year of fallow, respectively. In the first year after fallow, maize grain yield ranged between 0.43 and 2.39 t ha-1 and was significantly influenced by the fallow system. There was a marked decrease in maize grain on the pigeon pea fallow plots in the second year, ranging between 50 and 38.6 percent in Kumayili and between 42·6 and 17.6 per cent in Tingoli. After the two-year fallow period, increase of soil organic carbon on the pigeon pea fallow plot compared with the natural fallow plot was 30.5 per cent, and there was an improvement of total nitrogen (48.5 percent) and CEC (17.8 percent). Copyright © 2005 John Wiley & Sons, Ltd.