Influence of Cowpea and Soybean Intercropping Pattern in Sorghum on Striga (striga hermonthica) Infestation and System Productivity at Mechara, Eastern Ethiopia

Striga is a serious constraint to sorghum, millet, rice and maize production in the dry land zones of Africa Field experiment was conducted at Mechara Agricultural Research Center during ; to determine the effect of cowpea and soybean intercropping pattern on Striga hermonthica infestation in sorghum and to assess the effect of S. hermonthica and intercropping on system productivity. The treatments included two legume crops (soybean and cowpea), their  planting time (simultaneously and at first weeding of sorghum),three planting patterns of legumes (double alternate plants within sorghum plants, two rows in between two rows of sorghum and both double alternate plants and two rows in between two rows of sorghum) along with sole crops (sorghum, soybean and cowpea). The experiment was conducted in randomized complete block design with three replications. The results showed that cowpea proved significantly superior to soybean in reducing striga infestation. Though simultaneous planting of soybean with sorghum in double alternate plants and two rows in between two rows of sorghum had minimum Striga infestation, but it was statistically at par with cowpea planted simultaneously with sorghum under all the planting patterns and planting with first weeding in sorghum under double alternate plants and two rows in between two rows of sorghum. Interaction of legumes with planting pattern significantly influenced sorghum plant height and aboveground dry biomass yield, while legumes and their time of planting and time of planting and planting pattern had significant effect on crop stand count and kernel weight per head, respectively. Keywords : Cowpea, infestation level, intercropping, planting pattern, productivity, sorghum, soybean, Striga