Abstract:
Insemi arid areas ofNortheastern Ethiopia,sorghum productivity is highly constrained bymoisture stress and low soil fertility due to continuouscereal croppingand low levels of soilnutrients.Efforts togrowsorghumwith inorganic fertilizer alonearenot successful due tosevere soil degradation, high evaporationand low rainfall. Therefore, this experiment wasinitiatedwith theaim of synchronizing evaporation reductionmechanismand fertilizer.Fieldstudy was conducted at HabruWoreda of NorthWollo, Ethiopia in 2015 main(rain-fed)cropping season. Factorial combination of four nitrogen rates(N rates)(0, 46, 92,138 kg Nha
-1
) and three mulching types (non mulched (NM), teffstrawmulch (TSM), sorghum strawmulch (SSM)))were tested to examine their effectson selected soil propertiesand sorghumyield.The results revealed that application of SSM and TSM significantly increased soilmoisture by13.4%and 13.1%, respectivelycompared tonon-mulched plot. Sorghumyieldand yield components were also significantly affected by mulching types and N rates.Maturity datewasincreased bythe N rates, i.e., from103days for control (0N) to121.1daysfor 138 kg N ha
-1
.Interaction effect of N rates and mulching types gave bettersorghumgrainand dry matter yields. The highest grain (4.8 t ha
xv
-1
) and dry matter yield (12.7 t ha
) wereobtained from138kg N ha
-1
and SSM.The maximum N uptake and N use efficiency wereamounted to be 108.1 and 72.8 kg ha
-1
from mulched plots, respectively while that of nonemulched were (64.5 and 50.1 kg ha
-1
). Finally,based on the partial budget and sensitivityanalysis, the study recommends, that, the optimumN rates coupled with mulching forincreasedsorghumyield in order of importance are: SSM +138kgN ha
-1
, SSM+ 92 kgNha
-1
and TSM + 138 kg N ha
-1
N
