Please use this identifier to cite or link to this item:
Title: The Effect of Legumes on Nitrogen Dynamics and Performance of Wheat (Triticum aestivum L.) and Maize (Zea mays L.) in a legume-cereal cropping sequence in the Kenya Highlands
Authors: Cheruiyot, Erick Kimutai
Keywords: Legumes on Nitrogen Dynamics -- Legume-cereal Cropping Sequence
Issue Date: Aug-2000
Publisher: Egerton University
Abstract: Wheat (Triticum aestivum L.) and Maize (Zea mays L.) are the major food crops in Kenya. The country is not self-sufficient in wheat production as it imports over 60% of the local wheat consumption and it barely meets its maize requirement. The bulk of these two cereals are produced in the agricultural high potential Kenya Highlands. However, the level of production currently averaged at 2.0 ton ha" against a potential of 4.0 and 7.0 ton ha"for wheat and maize respectively, is low. Among the reasons responsible for the low yields is the declining soil fertility caused by prolonged cereal monoculture. This is exacerbated by the high costs of fertilizers. In an effort to provide remedial solution, biological intervention on soil nitrogen status for improved performance of the cereals was sought through productive management of the short-rains fallow with legumes. Experiments were set up at Egerton University (Njoro) and Rongai, in which five legumes were grown against continuous cereal and traditional weedy fallow during the October~December short-rains and followed by wheat and maize during the April-August long-rains season. The legumes were; chickpea (Cicer arierinum L.), field bean (Phaseolus vulgaris L.), soybean [Glycine max(L.) Merril], garden pea (Pisum sativum L.) and dolichos lab lab [Lablab purpureus (L) Sweet]. Biomass yield, nodulation, tissue N content, C/N ratio and seed yield were used to evaluate suitability of the legumes as fallow management species. Their effect on soil nitrate status and the response of a succeeding cereal (maize or wheat) test crop in the main season was also determined. Crop growth and development, grain yield and weed population in the succeeding test crop were measured. The traditional fallow provided larger biomass averaged at 2-3.6 ton ha“ against g 2.0 ton ha“ for the legumes with N content below 1.5% and C/N ratio greater than 20. Though legumes produced less biomass, N content was generally above 2% and C/N ratio varied between l0-l4 thereby giving better quality residue. Subsequently, improved soil N and performance of the succeeding wheat and maize was observed in the legume-managed plots. Notable observations were that crop biomass, tiller numbers, and spikelets in wheat, and leaf area index, ear numbers, and N-uptake in maize, were improved when the legumes preceded the cereals. Yields increases of up to 36% and 68% in wheat and maize, respectively, were obtained when ‘preceded by legumes against the traditional fallow with outstanding performance in the dolichos-managed fallow. Besides, weed population expansion was restricted in previously legume-managed fallow. Overall, dolichos emerged the most suitable fallow management species.
Appears in Collections:Faculty of Agriculture

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.