Effect of Sorghum-Mung Bean Intercropping on Sorghum-Based Cropping System in the Lowlands of North Shewa, Ethiopia

Due to decreasing land units and a decline in soil fertility, integrating mung beans into the Sorghum production system is a viable option for increasing productivity and producing cash crops. The experiment was conducted during the 2017 and 2018 cropping seasons in order to evaluate the effect of a Sorghum-mung bean intercrop arrangement on a Sorghum-based cropping system that would maximize intercropping advantage without reducing Sorghum performance. The treatments were combinations of sole Sorghum, sole mung bean, one Sorghum by one mung bean row (1 : 1), one Sorghum by two mung bean rows (1 : 2), two Sorghum by one mung bean row (2 : 1), and mixed planting of Sorghum and mung bean (50/50), which were tested in a randomized complete block design replicated four times. The highest yield reduction was observed from intercropping mixed planting (15.63%), in addition, the mean intercropped Sorghum yield showed up to12.44% reduction compared to sole stand. On the other hand, best-intercropped Sorghum yields that were produced under combinations of 2 : 1 row arrangement (4.11 t·ha−1) gave a statistically similar yield to all combinations including sole stand (4.48 t·ha−1). Significant row arrangement effect showed that the row (1 : 2) gave the highest yield for mung bean (0.35 t·ha−1), while the lowest was recorded from row arrangement (1 : 1) (0.16 t·ha−1). The highest total LER was obtained at 1 : 2 row (1.23) arrangements. The highest net return and marginal return (MRR) (341.23%) was obtained from one-row Sorghum alternated with two-row mung bean (1 : 2). Therefore, farmers around the research area can get additional income from intercropping Sorghum with bean crops without adversely affecting Sorghum yield by using one-row Sorghum alternated two-row mung bean (1 : 2) row arrangement.