EFFECTS OF PLANTING DENSITIES AND VARIETIES OF SOYBEAN [Glycine max L. (Merrill)] INTERCROPPED WITH MAIZE (Zea mays L.) ON THE PERFORMANCE AND PRODUCTIVITY OF THE COMPONENT CROPS AT CHIRO, EASTERN ETHIOPIA

Abstract

The experiment was conducted at Chiro District, Eastern Ethiopia, on Oda Bultum University experimental field during 2019-cropping season to assess the effects of planting densities and varieties in maize/soybean intercropping on yield related traits and yield of component crops and to identify the optimum plant density and compatible variety of soybean that maximizes productivity. Maize variety BH140at recommended population rate of 44,444plants/ha and three soybean varieties (Didesa, Ethio-Yugoslavia and Korme) with a three population density 25%, 50% and 75% of the recommended population density of sole soybean (500,000 plants/ha) accompanied with sole maize and sole soybean varieties were laid out in a factorial combination in Randomized Complete Block Design (RCBD) with three replications. Data on phenology, growth, and yield and yield related traits of both crops, and land equivalent ratio (LER), gross monetary value (GMV) and monetary advantage index (MAI) of the cropping systems were examined. The analysis of variance revealed, maize leaf area and leaf area index showed significant difference due to the associated soybean planting densities. Maize number of ears per plant was significantly affected by soybean varieties and planting densities while grain yield and harvest index were significantly affected by soybean varieties. Yield components and yield of soybean had also significantly affected by soybean varieties and planting densities and their interaction in maize and soybean additive intercropping. In general the yield obtained from sole cropped maize (4327 kg/ha) and sole soybeans (2137.35 kg/ha) were higher than the mean intercropped grain yield of maize (4094.3 kg/ha) and soybeans (1697.28 kg/ha).The LER showed significant difference due to the main effect of soybean planting densities. Generally, the highest LER (1.84) and GMV (73578 ETB/ha) were obtained from maize intercropped with Ethio-Yugoslavia at 50% planting densities. Among the varieties the highest MAI (26468ETB/ha were obtained from Ethio-Yugoslavia and 31763ETB/ha were obtained from 50% planting density. The result clearly indicated that the additive intercropping mixture of maize and soybean had an advantage over growing of either of them in sole.