Demonstration of maize-soybean (Glycine max (L) Merrill ) rotations in promotion for sustainable cropping system in Southwest Ethiopia

Abstract

Maize-soybean crop rotation system has positive impacts on the key indicators chosen for ecology, food and
nutrition, and socioeconomic conditions of smallholder farmers. The study was conducted at Omonada, and
Bedele districts of south west Ethiopia during 2017 and 2018 cropping season. Forty-nine farmers were selected in
two districts with the land holding of 20mX20m (400m2). Suitable varieties for each crop were selected and sown
based on agro-ecological features of the areas. Four cropping scenarios were arranged viz., Maize-after maize,
Soybean after soybean, Soybean after maize and maize after soybean in the two years period. The results of study
revealed that, mono-cropping of maize gives a minimum yield (7.84 and 6.98 t/ ha) as compared to Maize after
soybean rotation (8.38 and9.14 to/ha) in Omonada and Bedele districts respectively, which means that crop
rotating maize after soybean produced yield benefit of 3.33 and 15 percent in the respective districts respectively.
Net average revenue from maize production after soybean (66,330 birr) was more economical than the profit
obtained from maize monoculture (54,002 pair). The focus group discussion was made with the farmers on their
perceptions on maize-soybean rotation. They responded that soybean after maize has the advantage for increasing
yield, limits concentration of pests and diseases, reduces the stress of weeds and improves the soil fertility and
structure. Generally, maize after soybean farm is profitable business and both yield and profit obtained are above
breakeven. Therefore possible measures for adoption and expansion of this cropping system should get priority in
the country.