Forage yield and green manure potential of some annual and short-term perennial legumes at two sites in Ghana

Abstract

Five annual or semi-perennial legumes were evaluated for forage and green manure production at two sites. At Pokoase (Transition zone), Lablab purpureus, Mucuna pruriens, Crotalaria ochroleuca, Desmodium distortum and Macroptilium lathyroides were planted while at Nyankpala (Guinea savanna zone), L. purpureus, C. ochroleuca, D. distortum, M. lathyroides and Clitoria ternatea were used. Herbage yields, plant heights and crude protein, ash and calcium contents of herbage of the legumes were determined. Soils under the different legumes at Pokoase were also analysed for nitrogen, available phosphorus, available potassium, organic carbon and organic matter contents. The study showed that the large-leaved and decumbent species Lablab purpureus and Mucuna pruriens and the erect Macroptilium lathyroides showed very good attributes in forage and green manure production. Herbage yields in the three species at the Pokoase site exceeded 6 t/ha whilst crude protein contents were high and in the range 14.71 to 17.38%. At Pokoase soils under Lablab purpureus and Mucuna pruriens showed high N contents (> 0.5% whilst Macroptilium lathyroides improved soil organic matter content more than any other species. M. lathyroides also resulted in the highest contents of available P and K in the soil compared to the other legumes.

JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 1 Number 2, January (1999) pp. 26-31