Dry-season sesbania fallows and their influence on nitrogen availability and maize yields in Malawi

dc.creatorIkerra, S. T
dc.creatorMaghembe, J. A
dc.creatorSmithson, P. C
dc.creatorBuresh, R. J
dc.date.accessioned2022-05-07T08:27:17Z
dc.date.accessioned2025-08-05T07:47:05Z
dc.date.available2022-05-07T08:27:17Z
dc.date.created2022-05-07T08:27:17Z
dc.date.issued2001
dc.description.abstractNitrogen deficiency is widespread in southern Africa, but inorganic fertilizers are often unaffordable for smallholder farmers. Short-duration leguminous fallows are one possible means of soil fertility restora- tion. We monitored preseason topsoil (0 to 20 cm) ammonium and nitrate, fallow biomass production and grain yields for three years in a relay cropping trial with sesbania [Sesbania sesban (L.) Merr.] and maize (Zea mays L.). Sesbania seedlings were interplanted with maize during maize sowing at 0, 7400 or 14,800 trees ha –1 , in factorial combination with inorganic N fertilizer at 0 or 48 kg N ha –1 (half the recommended rate). After maize harvest, fallows were allowed to grow during the seven-month dry season, and were cleared before sowing the next maize crop. Both sesbania fallows and inorganic N fertilizer resulted in significantly greater (P < 0.01 to 0.05) preseason topsoil nitrate-N than following unfertilized sole maize. In plots receiving no fertilizer N, preseason topsoil inorganic N correlated with maize yield over all three seasons (r 2 = 0.62, P < 0.001). Sesbania fallows gave significantly higher maize yields than unfertilized sole maize in two of three years (P < 0.01 to 0.05). Sesbania biomass yields were extremely variable, were not significantly related to sesbania planting density, and were inconsistently related to soil N fractions and maize yields. Short-duration fallows may offer modest yield increases under conditions where longer duration fallows are not possible. This gain must be considered against the loss of pigeonpea (Cajanus cajan L. Millsp) harvest in the similarly structured maize-pigeonpea intercrop common in the region.
dc.identifier0167-4366
dc.identifierhttps://www.suaire.sua.ac.tz/handle/123456789/4077
dc.identifier.urihttp://repository.costech.or.tz/handle/20.500.14732/100264
dc.languageen
dc.publisherKluwer Academic Publishers.
dc.subjectZeamays
dc.subjectImproved fallow
dc.subjectInorganic nitrogen
dc.subjectMineralization
dc.subjectNitrogen fertilizer
dc.subjectRelay intercrop
dc.titleDry-season sesbania fallows and their influence on nitrogen availability and maize yields in Malawi
dc.typeArticle

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