The impact of drought on sorghum production, and farmer's varietal and trait preferences, in the north eastern Ethiopia: implications for breeding

摘要

Purpose: Sorghum [Sorghum bicolor (L.) Moench] has been cultivated for centuries as a staple food crop for millions of people in sub-Saharan Africa and Asia. In Ethiopia a total of 4.34 million tons of sorghum is being produced per annum, predominantly in the arid and semi-arid areas. However, the yield and quality of sorghum is affected by a wide array of production constraints, notably severe and recurrent drought stress. The aim of this study were to determine the impact of drought on sorghum production and productivity over time and space, and to identify farmers' trait preferences, production constraints and coping strategies when dealing with drought in north eastern Ethiopia.Materials and methods: Participatory rural appraisal (PRA) was employed in three administrative zones of north eastern Ethiopia. One Woreda from each Zone and two Kebeles from each Woreda were selected on the basis of sorghum area coverage, production, consumption and prior information on the intensity, duration and spatial coverage of drought. In each kebele, 30 respondents were selected for interview and 12 key informants were selected for group discussions and transect walk personal observations. Data collected from 180 respondents was subjected to statistical analysis and the information gathered from 72 key informants through focus group discussions and transect walk observations were used in discussing the results.Results and discussion: The present study found that productivity of sorghum was challenged by recurrent droughts, Striga infestation, insects, birds, diseases, a lack of varieties with farmers-preferred traits and high yield potential, limited policy support, a lack of improved seed system, poor sorghum production practices and application of crop input and poor soil fertility, in a decreasing order of importance. Among the listed sorghum production constraints, severe drought in the post-flowering stage was identified by most interviewed farmers as the leading constraint across the three study zones. Focus group discussions and transect walk observations held in each Kebele revealed that farmers' had lost numerous valuable local landrace varieties due to extreme drought conditions over the years. A significant number of interviewed farmers preferred to grow high grain and biomass yielder medium-maturing sorghum varieties which can be sown at the normal planting time but which would escape post-flowering drought.Conclusion: Overall, sorghum breeding programme should be directed at developing farmers' ideal sorghum varieties with high grain and biomass yield, adequate level of drought and Striga tolerance. In addition, development of farmer preferred medium-maturing sorghum varieties suitable for April planting should be strengthen to boost its productivity and to increase varietal adoption rate in the area.