On-farm evaluation of an animal-drawn implement developed in Ethiopia for row placement of wheat seed and basal fertiliser

Abstract

Grass weeds are difficult to control by hand weeding in a broadcast wheat crop because several species are not easily distinguished from the crop at an early stage. Chemical weed control, on the other hand, can be highly effective, but is limited in Ethiopia by the unavailability and high cost of herbicides. Further, dependence on high efficacy herbicides to control grass weeds can result in weed species shifts and/or the development of resistant weed biotypes. Row sowing of wheat can facilitate hand and/or mechanical weeding by enabling farmers to identify grass weeds in the inter-row spaces. However, manual row seeding is extremely labour intensive and unacceptable to peasant farmers in Ethiopia. Row seeders developed elsewhere have not been accepted in Ethiopia because they were either too labour inefficient or ineffective in cloddy and rough fields. Therefore, a four-row seeder has been developed in Ethiopia with a new type of seed metering mechanism. Field tests have shown that the row seeder can work effectively in fields prepared by ox plough. The row seeder is labour efficient, requiring less than 25% of the time per unit area compared to the farmers' conventional practice of broadcasting seed and fertilizer and covering by ox plough. The seeder also facilitates placement of seed and fertilizer together in the row, enabling the crop to utilise fertiliser more effectively and limiting the nutrients available to weeds emerging between crop rows. In one season, use of the row seeder increased wheat grain yield by 28% in comparison to the conventional broadcasting. The row seeder used in conjunction with an inter-row weeder was the most profitable package tested on farmers' fields in 1995 and 1996, representing a sustainable production technology for peasant wheat farmers in Ethiopia.