Creating niches for integration of green manures and risk management through growing maize cultivar mixtures in Southern Ethiopian Highlands
Date
2006
Journal Title
Journal ISSN
Volume Title
Publisher
AHI, Kampala, UG
Abstract
Maize yield fluctuation in small scale farms of East Africa is associated mainly to intermittent drought, soil fertility decline and choice of intercrops. Field experiments were conducted between 2000 and 2004 in Areka, Southern Ethiopia to evaluate whether maize cultivar mixtures have yield advantage over pure stands under sub-optimal conditions but also to quantify the productivity of vetch (Vicia dasycarpa) as a green manure crop under intercropping with maize mixtures or pure stands. Mid-late maturing, A511 (145 days, 2.45m tall) and early maturing, ACV6 (120 days and 2.04m tall) maize varieties were grown either in pure stands or in mixtures of the two cultivars with or without intercropping, in fertile or less fertile farm plots. Under sole cropping, the grain yield of mixtures was significantly higher (by 1.5 tha-1) (P<0.05) than early variety, cv ACV6, but lower than the late maturing variety, cv A511, across years. Similarly, the grain yield of mixtures was significantly higher than sole cv ACV6 but lower than A511 in fertile plots while ACV6 out yielded both late maturing variety and the mixtures in less fertile plots. Intercropping with vetch did not affect the yield of mixtures while it caused a significant yield decline in A511, by about 35% (p<0.05), particularly in years with intermittent drought. On the other hand, vetch biomass was significantly reduced under intercropping with maize, by 94% in A511 but 66% in mixtures. Vetch was more sensitive to low soil fertility than maize. Farmers’ evaluation indicated that cultivar mixtures could intensify their systems by leaving space for intercropping, shortening hunger period, minimizing risk of complete crop failure and as a stake. However, the adoption of this technology would depend on the availability of compatible varieties with similar grain colour, size and shape that otherwise would affect the market value of the produce.
Description
item.page.type
Working Paper
item.page.format
Text
Keywords
AGRICULTURAL PRODUCTIVITY, SYSTEMS INTENSIFICATION, CULTIVAR MIXTURES, INTERCROPPING, MAIZE, LEGUMINOSAE, CROP YIELD, ETHIOPIA