Plant nutrient aspects of mulch incorporation in alley cropping trials of semi-arid Machakos, Kenya
Abstract
Experiments on plant nutrient status and yield of maize in relation to mulch nutrient
composition were conducted at Katumani, in Machakos district from 1987 to 1989. In all
the seasons, Katumani B Composite was sown, apart from short rains of 1988,when hybrid
511was planted.
Cassia siamea had been grown as the tree species forming the hedges. Between the hedges,
3 maize rows were sown parallel to the hedges. The hedges were lopped periodically at a
height of 50 em and the loppings fully incorporated into the soil within the hedges (alleys)
before the beginning of each season. In the control plots, each hedge row was replaced by
a row of maize and no mulch incorporated.
Nutrient analysis was performed primarily for macronutrients N,P,K,Ca and Mg for Cassia
loppings, maize leaves, maize grains and maize stovers. Maize yield (grains) in g/row and
weed biomass were also assessed. Decomposition for Cassia siamea loppings using standard
litter bags was also monitored.
The results indicated that incorporation of mulch increased the nutrient concentrations of
maize leaves, grains, and stovers as revealed by higher levels of nutrient concentrations in
the treated plots relative to the controls. Although there was a relatively higher yield in the
treated plots as compared to the controls on per row basis, the differences were not
significant. The weed biomass in the treated plots was more than in the control plots.
Decomposition experiments indicated that approximately 70-90% of Cassia mulch dry matter
could be lost within 60 days
Citation
M.Sc. ThesisSponsorhip
University of NairobiPublisher
Faculty of Science, University of Nairobi
Description
Master of Science Thesis