dc.contributor.author | Whitbread, Anthony M. | |
dc.contributor.author | Jiri, Obert | |
dc.contributor.author | Maasdorp, Barbara | |
dc.date.accessioned | 2020-11-20T10:16:50Z | |
dc.date.available | 2020-11-20T10:16:50Z | |
dc.date.issued | 2004-01-22 | |
dc.identifier.citation | Whitbread, A. M., Jiri, O., and Maasdorp, B. (2004). The effect of managing improved fallows of Mucuna pruriens on maize production and soil carbon and nitrogen dynamics in sub-humid Zimbabwe. Nutrient Cycling in Agroecosystems 69: 59–71. | en_ZW |
dc.identifier.uri | https://hdl.handle.net/10646/3941 | |
dc.description.abstract | Mucuna pruriens has emerged as a successful forage or green manure legume for use in the smallholder animallivestock
systems of Zimbabwe. The efficiency of N recovery from mucuna residues in subsequent maize crops
can be low and the loss of nitrate nitrogen from the soil profile prior to maize N demand is proposed as a reason
for this. An experiment was established in the 1999–2000 wet season at seven on-farm sites in a communal
farming district of Zimbabwe average rainfall 650–900 mm on acidic pH 5 , and inherently infertile soils
with texture ranging from sandy/sandy loam n 5 to clay n 2 . Improved fallows of mucuna grown for 19
weeks produced between 4.7 and 8.5 t/ha dry matter DM at the sandy/sandy loam sites and between 9.5 and
11.2 t/ha DM at the clay sites. This biomass was then either cut and removed as hay, or ploughed in as a green
manure. Weedy fallow treatments, which represent typical farmer practice, produced 3.3–6.3 t/ha DM. A maize
crop was then grown on these same sites in the following 2000–2001 wet season and the dynamics of soil N and
C and maize production were investigated. Where mucuna was green manured, a positive linear response r2
0.72 in maize yield to increasing mucuna biomass containing 101–348 kg N/ha was found. On the sandy sites,
and where no P fertiliser was applied to the previous mucuna phase, a maize grain yield of 2.3 t/ha was achieved
following the mucuna green-manure system; this was 64% higher than the maize yield following the weedy fallow
and 100% higher than the maize yield following the mucuna ‘removed’ hay system. Apparent nitrogen recoveries
in the range of 25 to 53% indicate that there are large quantities of nitrogen not utilised by the subsequent
maize phase. The loss of 73 kg/ha of nitrate N from the soil profile 0–120 cm early in the wet season and prior
to maize N demand is proposed as a reason for low N recovery. No change in labile C measured with 333 mM
KMnO4 was detected through the soil profile at this time and it is suggested that labile C movement occurred
between the sampling times. | en_ZW |
dc.language.iso | en | en_ZW |
dc.subject | Green manure | en_ZW |
dc.subject | Maize response | en_ZW |
dc.subject | Mucuna pruriens | en_ZW |
dc.subject | Nitrate leaching | en_ZW |
dc.subject | Soil carbon | en_ZW |
dc.subject | Soil nitrate | en_ZW |
dc.title | The effect of managing improved fallows of Mucuna pruriens on maize production and soil carbon and nitrogen dynamics in sub-humid Zimbabwe | en_ZW |
dc.type | Article | en_ZW |
dc.contributor.authoremail | anthony.whitbread@csiro.au | en_US |