last final thesis of umer

The Somali Regional State has a bimodal pattern of rainfall regime. Hence, there are two cropping
seasons: The relatively long rainy season (March to April) locally called Gu and the short rainy
season (October to November) locally called Deyr. The later characterize the lowland parts of the
Ogaden basin while the highland parts of the region, mainly Jijiga and its surrounding have Gu
and Kiremt (July to September) as their cropping seasons (IPS, 2002).
According to the National Meteorological Service Agency (NMSA, 2000), the mean annual
rainfall which is 660 mm is bimodal (Figure 3). In the zone, there is generally low, unreliable and
uneven distribution of rainfall. The mean monthly minimum temperature varies from 5.8 0 C in
November to 14 0 C from July to September and the mean monthly maximum temperature varies
from 25 0 C in July to 29 0 C from March to April. In addition high runoff rates coupled with high
evaporation rates make the available rainfall insufficient especially for crop production.
Figure 3. Rainfall pattern at Jijiga Station. (Devereux, 2006)
3.2 Experimental materials
The experimental materials used were seeds of improved maize variety melkassa-4 (ECA-EE-36)
and cowpea varieties that were released by Melkasa Research Center (Kenketi, Black eye bean
and Bole). These materials were obtained from Melkasa Agricultural Research Center.
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