Skip‐Row Planting and Tie‐Ridging for Sorghum Production in Semiarid Areas of Ethiopia

Soil water deficits during grain fill have been estimated to reduce sorghum [ Sorghum bicolor (L.) Moench] grain production in Ethiopia by 300,000 Mg yr −1 The potential for skip‐row planting and its integration with tie‐ridging was evaluated for increasing sorghum grain yield in Ethiopia. Skip‐row planting is a means of saving soil water for the grain‐fill period while tie‐ridging is intended to improve soil water availability by reducing runoff. The skip‐row treatments were: no skipped rows (S0:0); one planted alternated with one skipped row (S1:1); two planted alternated with two skipped rows (S2:2); and two planted alternated with one skipped row (S2:1). The tillage treatments were flat tillage and tie‐ridging. Eight trials were conducted. Grain yield in northern Ethiopia was 50% more with S2:1 compared with S0:0. There was no grain yield advantage to S1:1 compared with planting all rows and a yield loss with S2:2. In northern Ethiopia, there was also a grain yield increase with tie‐ridging compared with flat tillage and a positive interaction between tie‐ridging and skip‐row planting. Striga [ Striga hermonthica (Delile.) Benth. and Striga asiatica (L.) Kuntze] infestation in northern Ethiopia was reduced by 70% through a combination of tie‐ridging, skip‐row planting, and variety choice. Tie‐ridging and skip‐row planting did not result in increased grain yield in central Ethiopia. The results of this research support the use of tie‐ridging and S2:1 planting where serious striga infestation and severe late‐season stress caused by soil water deficits are common such as in northern Ethiopia.