Determination of optimum spatial arrangement and plant population in sesame sorghum intercropping

Information regarding sesame in sorghum intercropping is very little. The present study was undertaken to determine optimum proportion of component crops and to compare the land use efficiency and economic returns of the component crops of sorghum/sesame intercropping system and enhance food security in Mieso area of oromiya region. The experiment was laid out in factorial Randomized Block Design with three replications. The treatment consists of three spatial arrangements (1:1, 2:1 and 2:2 of sorghum: sesame), three intra-row spacing of sesame (5 cm,10 cm and 15 cm) and sole crop of component crops. Intercropping significantly (P<0.05) decreased yield of sesame compared to pure stand. The grain yield of sesame in intercropping (91.0 kg ha-1) was very low compared to sole sesame (430.kg ha-1) which was nearly five times high. Spatial arrangement had statistically (P<0.05) a noticeable influence on the grain yield of sesame. The highest grain yield 110 kg ha-1 and 100 kg ha-1 were found in 1:1 and 2:1 sorghum: sesame arrangements respectively whereas, the lowest (70 kg ha-1) grain yield was found in 2:2 sorghum: sesame arrangement. The main effect of spatial arrangement and intra row spacing were significantly affected the partial LER of sesame despite their interaction were non-significant. Maximum partial LER of sesame (0.22) was observed at 10 cm intra row spacing while the lower partial LER (0.19) was calculated at 15 cm intra row spacing. Maximum LER value (1.33) was observed at 1:1 sorghum: sesame arrangement whereas the minimum LER value (1.26) was recorded under 2:1 sorghum: sesame arrangement. Closer intra row spacing (5 cm) showed LER of 1.32 while the other wider intra row spacing showed 1.27 total LER each, in fact, the difference was statistically insignificant (P>0.05). This study concluded that intercropping sorghum and sesame in one to one ratio (1 row sorghum: 1 row sesame) found to be appropriate at Mieso agro ecology. Moreover, all arrangements resulted above the yield of sole cropping. Sowing of sesame in 5 and 10 cm intra row spacing under sorghum/sesame intercropping was preferable.