On-farm study was conducted in the lowland areas of Kewot district in the North Shewa Zone, Ethiopia on two sites during 2011 crop season to determine optimum seed rate of sesame. Four seed rates (2, 4, 6 and 8 kg ha . Since the statistical analysis revealed non-significant difference among treatment yields, comparison was made by using total costs that vary. Accordingly, 2-4 kg ha -1 seed rate found to be optimum for the production of sesame under rain-fed condition around Kewot district and similar areas.

Field experiments were carried out to study the response of two lentil varieties to varying sowing dates in a split plot design with three replications, in which varieties were assigned to main plots and sowing dates to sub plots. The study was conducted at Enewari research site of Debre Birhan agricultural research center for three consecutive years (2007 - 2009) on two soil types. The results showed that no significant difference between varieties for grain yield. However, variety Alemaya produced highest grain yields of 1.3 t/ha and 1.22 t/ha from fifth (30-July) sowing date on heavy and relatively light Vertisols respectively. On the other hand, the local variety produced highest grain yields of 1.4 t/ha and 1.06 t/ha on the fifth and six sowing dates on heavy and relatively light Vertisols respectively. Grain yield proportionally increased with increasing biological yield in different sowing dates on both soil types. On heavy Vertisol varieties responded differently to the changes of sowing dates. Variety Alemaya had responded to a wider sowing dates. Early August to mid-August sowing found to be optimum for local variety. On light Vertisol, the functional relationship was unexplained for both varieties. In general, heavy Vertisol gave higher responses than relatively light vertisol throughout most parameters and levels tested.