Progress 01/02/02 to 06/30/07
OUTPUTS: This project focused on soil and water management for improving sorghum production in eastern Africa, with some activities in southern Africa. Enhancement of research and extension capacity in host countries was of high priority and included partial or full support enabling six graduate students from Ethiopia, Mozambique, Latin America, and the US to earn MSc or PhD degrees. A researcher from Ghana is continuing with PhD studies at UN-L. Four collaborators from Africa attended an IFDC-organized short course on integrated soil fertility management. On-going technical support to collaborators was an important part of enhancing institutional capacity.Increasing yield as a means to promote economic growth and improve human nutrition in semi-arid areas has been the objective of research and extension activities. In Ethiopia, tie-ridging resulted in 45% more available water; grain yield with traditional practices was 45 and 62% of the yield with the best tie-ridging practice. In
another study, sorghum yield with tie-ridge tillage was the same as flat planting where 3 Mg ha-1 of crop residue had been applied as ground cover and 75% more than flat planting with no ground cover. In a third study, highland pulse yield was increased by a mean of 70% with tie-ridging compared with flat planting. Oxen drawn implements for tie-ridging and row planting were verified with farmers as suitable for tie-ridge systems. Extension efforts to promote tie-ridging were enhanced. Evaluation of skip-row planting as a means to improve water availability during grain-fill is underway. In Uganda, several soil fertility management and tillage practices were found to be economical for resource poor farmers through a process of farmer participatory research; extension efforts to promote soil fertility management options were established while evaluation of sustainability issues associated with these management practices continues. In Mozambique, research on integrated soil fertility
management was initiated. In central Tanzania, research addresses tillage options to conserve water and enable more timely planting. Information was compiled for five countries in eastern and southern Africa (ESA) and published The Atlas of Sorghum Production in Five Countries of Eastern Africa. An analysis of sorghum production constraints was done. In Nebraska, several studies addressed opportunities to improve the profitability of grain sorghum production. The use of starter fertilizer and row cleaning under no-till conditions was not profitable. An N use recommendation for the sorghum-soybean rotation was developed that considers expected yield and the prices for N and grain. One-time tillage of no-till reduced nutrient stratification and the potential for dissolved P runoff with no negative effect on soil organic C content, soil physical properties, microbial communities, or yield. Skip-row planting of sorghum was found to have a yield advantage at 2 of 4 western Nebraska sites
and no yield disadvantage at the other 2 sites.
PARTICIPANTS: Dr. Martha Mamo, Associate Professor of Soil Science, Department of Agronomy and Horticulture, University of Nebraska-Lincoln
Outcomes/impacts of activities to improve sorghum production in eastern Africa include: 1) significant additions to the body of scientific knowledge on sorghum production in semi-arid areas of eastern Africa that is regularly accessed by peer researchers and extension specialists; 2) more knowledgeable and informed researchers, including four who were partially supported for graduate degrees by this project and those who gained skills and knowledge through collaborative research activities; and 3) extension field staff who received training under the project. Impact on behavior is well illustrated by improvements in research conducted by African collaborators which is providing solutions to real problem problems but also results that are being published in international scientific journals; some have also become more effective in writing grants and obtaining buy-in funding. While extension activities are underway, it is early to assess the impact on famers'
- Kaizzi, C.K., J. Byalebeka, C.S. Wortmann, and M. Mamo. 2007. Low input approaches for soil fertility management in semi-arid eastern Uganda. Agron. J. 99: 847-853.
- Wortmann, C.S., M. Mamo, and A. Dobermann. 2007. Nitrogen response of grain sorghum in rotation with soybean. Agron. J. 99:808-813.
- Wortmann, C. 2006. Phaseolus vulgaris L. (common bean). In: Brink, M. & Belay, G. (Ed). Plant Resources of Tropical Africa 1. Cereals and Pulses. PROTA Foundation, Wageningen, Netherlands / Blackhuys Publishers, Leiden, Netherlands / CTA, Wageningen, Netherlands. Pp 146-151.
- Wortmann, C.S., M. Mamo, G. Abebe, K. Kaizzi, C. Mburu, E. Letayo, and S. Xerinda. 2006. An Atlas of Sorghum Production in Eastern Africa. http://intsormil.org.
Progress 10/01/05 to 09/30/06
Promote economic growth, improve nutrition, increase yield. Opportunities to increase yield or to reduce production costs have been identified while promising research is continuing and technology dissemination activities have been initiated. Following verification and fine-tuning of the targeting of tied-ridge tillage for semi-arid areas of Ethiopia, extension efforts have been initiated while other aspects of tie-ridge technology are under investigation. Four opportunities for low-input management of soil fertility in semi-arid eastern Uganda have been verified as economical using farmer participatory approaches; information dissemination is underway and more detailed research has been initiated to assess the sustainability of these practices. Research on tillage alternatives commenced in 2005 in Tanzania. The study of some effects of occasional tillage for no-till systems has been completed while investigation of other aspects continues. Skip row planting as a
means to reduce the effects of water deficits on yield is being investigated at three locations in Ethiopia and five locations in Nebraska. The institutional capacity for research was enhanced in Ethiopia, Uganda, Tanzania, and Mozambique. Gebreyesus Brhane and Tewodros Mesfin from Ethiopia, and Dr. Kaizzi Kayuki came to the University of Nebraska-Lincoln as visiting scientists and all presented papers at the ASA Annual Meetings. Also, four scientists from Ethiopia, Tanzania, and Mozambique were sponsored for a short course in Ghana. Extension training was conducted in Ethiopia. A US and two international graduate students have completed their degrees with support from this project. An atlas of sorghum production in eastern Africa has been published and distributed which is expected to improve institutional capacity by providing information useful for national and regional planning. A paper was published reporting results of tied-ridge research in Ethiopia and a decision guide to use
of tied-ridging has been prepared for the extension service. Low input soil fertility management practices have been verified in Uganda and extension efforts to promote these have commenced; a paper is under review with Agronomy Journal. Tillage research is underway in Tanzania and the potential for improved water use efficiency and drought avoidance using skip row planting of sorghum in Ethiopia is being studied. Sorghum research in Nebraska has addressed: N requirement for sorghum grown after soybean and a paper has been accepted by AgronJ and an extension publication prepared; starter fertilizer and row cleaning for no-till situations with two journal papers and extension material published; one-time tillage as a means to improve no till systems has been investigated and five papers have been submitted to journals.
Assuming adoption of tied-ridge planting on 20% of Ethiopia's sorghum 2M ha of production area with added profit of $10/ha, the expected impact is $4,000,000/yr. Assuming adoption of low-cost soil fertility management practices on 60,000 ha in Uganda with an added profit of $15/ha, expected impact is $900,000/yr. Assuming adoption of advice on starter fertilizer and row cleaning on 30,000 ha in Nebraska with a benefit of $6/ha, expected impact is $180,000/yr. Assuming adoption of N recommendations in Nebraska on 70,000 ha for a benefit of $10/ha, expected impact is $700,000/yr.
- Wortmann, C.S. and M. Mamo. 2006. Starter fertilizer and row cleaning did not affect yield of early planted, no-till grain sorghum. Crop Management J. Nov. 2006. http://www.plantmanagementnetwork.org/cm/element/cmsum2.asp?id=5814
- Brhane, G., C.S. Wortmann, M. Mamo, H. Gebrekidan, and A. Belay. 2006. Micro-basin tillage for grain sorghum production in semi-arid areas of northern Ethiopia. Agronomy Journal 98:124-128.
- Wortmann, C.S., S.A. Xerinda, and M. Mamo. 2006. No-till row crop response to starter fertilizer in eastern Nebraska: II. rainfed grain sorghum. Agronomy Journal. 98: 187-193.
- Wortmann, C.S., M. Mamo, G. Abebe, K. Kaizzi, C. Mburu, E. Letayo, and S. Xerinda. 2006. An atlas of sorghum production in five countries of eastern Africa. http://www.intsormil.org.
- Hergert, G.W., and C.S. Wortmann, 2006. Using starter fertilizer for corn, grain sorghum and soybeans. NebGuide G361. University of Nebraska-Lincoln.
Progress 10/01/04 to 09/30/05
Opportunities to increase yield or to reduce production costs have been identified while promising research is continuing and technology dissemination activities have been initiated. Following verification and fine-tuning of the targeting of tied-ridge tillage for semi-arid areas of Ethiopia, extension efforts have been initiated with training workshops conducted for extension workers in two locations. A decision guide for targeting of tied-ridging has been developed, two papers were presented at the 2004 ASA meeting, and a paper has been accepted by Agronomy Journal. Additional research has been initiated on tied-ridging by soil fertility interactions and on skip-row technology as a means to improve soil water availability during grain fill. Four opportunities for low-input management of soil fertility in semi-arid eastern Uganda have been verified as economical using farmer participatory approaches; information dissemination is to begin with the second season of
2005; and more detailed research has been initiated to assess the medium-term sustainability of these practices. Preliminary research was conducted on tillage and soil fertility management alternatives in Mozambique. A study of sorghum production areas in Ethiopia, Uganda and Kenya has revealed stalk borer, water deficits, striga, bird damage, N deficiency, weeds and shootfly as the greatest causes of yield loss. Results of research on how soil properties relate to P availability for diverse soils of eastern Africa was presented at the 2004 ASA meeting. A paper has been accepted by Agronomy Journal reporting the results of the first phase of starter fertilizer research for no-till sorghum production in eastern Nebraska. The second phase of this research was completed in 2005 and a paper is under review for the Crop Management Journal. Field research for fine-tuning N recommendations has been completed; the results of 39 trials are being analyzed. Research on occasional tillage to
improve the productivity of no-till sorghum production systems continues as the dissertation and thesis research of two graduate students; three papers are to be presented at the 2005 ASA meeting.
Promotion of very promising practices is underway in Ethiopia and Uganda. Advice derived from starter fertilizer research has the potential to reduce production costs for some farmers. The N rate research shows that farmers can significantly reduce N rates, especially given increased fertilizer costs.
- Wortmann, C.S., S.A. Xerinda, and M. Mamo. 2006. No-till row crop response to starter fertilizer in eastern Nebraska: II. rainfed grain sorghum. Agronomy Journal. accepted
- Brhane, G., C.S. Wortmann, M. Mamo, H. Gebrekidan, and A. Belay. 2006. Micro-basin tillage for grain sorghum production in semi-arid areas of northern Ethiopia. Agronomy Journal.
Progress 10/01/03 to 09/30/04
Researchers working with farmers in Ethiopia have verified that tie-ridge tillage can result in higher yields in many places. Nearly all farmers found tie-ridging to be superior to their practice of flat cultivation for runoff control and crop performance. A tie-ridger was seen as culturally appropriate and rated well for agronomic effectiveness, usability and affordability. Thesis research on soil and water management was supported for two MS students at Alemaya University, Ethiopia. Thesis I: application of 3 t/ha of crop residues after tillage resulted in significant yield increases for no-till and conventional tillage; tie-ridging had a relatively high yield with no crop residue applied; and soil water availability was greater throughout the season with tie-ridging as compared to other tillage practices. Thesis II: tie-ridging either before planting or at planting resulted in better soil water conditions and grain yield than tie-ridging at weeding time or with
traditional tillage practices. Preparations are underway to conduct training workshops for extension staff in early 2005 on practices to reduce water loss and to improve efficiency of water and nutrient use. Problems were identified and prioritized and research topics were determined in 2003 with farmers in four communities of Uganda. Three topics are being addressed: the use of low levels of fertilizer and manure; N credits from rotations with cowpea or green gram as compared to mucuna; and the development of a reduced tillage system with farmers. Phosphorus sorption isotherms were determined for 36 soil samples collected from Ethiopia, Uganda, and Mozambique. Percent clay content was generally well correlated with P sorption maximum. P sorption maximum increased moving south from Entisol and Inceptisol of northern Ethiopia to the more developed central and eastern vertic soils. Phosphorus sorption maxima were 44 to 390% higher in sandy soils of Uganda and Mozambique with termite
mounds as compared to the nearby sandy soils. The texture of soil in termite mounds was finer than for the surrounding sandy soil which accounts for some of the increase in P sorption capacity. P sorption maxima decreased by about 8% in fine-textured soil influenced by termites. P sorption of Uganda and Mozambique soils were well correlated with extractable Al but not Fe, and extractable aluminum was more with termite modified sandy soils. Nineteen sorghum production areas were delineated in Ethiopia, Kenya and Uganda and for these three countries and attribute data were obtained through interviews with sorghum experts on 45 production constraints, preferences for 11 phenotypic characteristics, 6 socio-economic issues, 6 sorghum cropping systems and management practices, and the importance of 15 uses of sorghum products. Production data have been obtained for Ethiopia at the Wereda level and for Uganda at the county level while preparations have been made to obtain these data for
Kenya. A contract has been made with a GIS expert in Uganda to compile the data into database and GIS formats, integrate data with soil and climate layers, analyze data, and create tables and maps.
The profitability of sorghum production will improve in Nebraska and in eastern Africa through the development and adoption of environmentally sound production practices.Sorghum research capacity has been enhanced as two graduate students from Ethiopia and another from Mozambique completed their MS degrees.
- Xerinda, S.A. 2004. No-till corn and grain sorghum response to starter fertilizer in Eastern Nebraska. MS thesis, University of Nebraska-Lincoln.
- Xerinda, S., C. Wortmann, M. Mamo, C. Shapiro. 2003. Starter fertilizer for no-till row crop production in Eastern Nebraska. American Society of Agronomy National Meeting, Denver, CO, Nov. 2-6.
- Mesfin, T. 2004. Effect of in-situ water harvesting on the growth, yield and water use efficiency of sorghum (Sorghum bicolor (L.) Moench) under semi-arid conditions of Ethiopia. MS thesis, University of Alemaya.
- Brhane, G. 2004. Tied ridging as in situ rain water harvesting method for improving sorghum (Sorghum bicolor L.) yield at Abergelle Area, Tigray Regional State. MS thesis, University of Alemaya.
Progress 10/01/02 to 09/30/03
Nutrient and water management research in Ethiopia. Ethiopian farmers identified water and nutrient deficits and Striga as major constraints to sorghum production. Farmers evaluated tie-ridging using a modified traditional plow and found it easy to use with acceptable draft power requirements but not very good on stony soil. Farmers also evaluated an oxen-drawn row planter and found it appropriate as it was easy to use and gave good placement of seed and fertilizer. Farmers thought that tie-ridging and conservation tillage would be appropriate in their communities with conservation tillage preferred for stony or sandy soils and for those with inadequate access to draft power. In 2002, 6 trials were successfully implemented and grain and biomass yields were 142 and 88% more with fertilizer applied as compared to no fertilizer, but there was no effect of tillage method. P fixation of soil In Ethiopia and Uganda. Phosphorus sorption isotherms were determined for 30 soil
samples. P sorption maximum (PSM) and P saturation index (PSI) were well correlated. PSM was more in central and eastern than in northern Ethiopia, and red soil exhibited much less P holding capacity than nearby black soil. Sand and clay contents of Uganda soils affect PSM. For sandy soils, soil from termite mounds had greater PSM than nearby soils but v.v. for clay loam soils. Nutrient and water management research in Uganda. Research was initiated with approximately 90 farmers in four communities in 2003. Using a participatory approach, problems and research topics were prioritized. On-farm research was conducted during the first season of 2003. Application of 3 t/ha manure or 30 and 10 kg/ha of fertlizer N and P resulted in more yield. Mucuna as a cover crop was relay intercropped with sorghum with no loss of sorghum yield. The effects of cowpea and green gram preceding sorghum in rotation on sorghum yield are being evaluated. Exploratory research is underway with farmers to
develop a reduced tillage system. Starter fertilizer for no-till sorghum production in Nebraska. Twelve dryland grain sorghum trials were established after soybean in 2002 and 2003 on rolling land in eastern Nebraska. Sorghum response to starter fertilizer (N+P or N+P+S) occurred in some trials but the responses were infrequent, small, and inconsistent. Including S in the starter fertilizer did not have an effect on sorghum yields. Tillage and soil quality in Nebraska. Research was initiated to determine if occasional tillage (e.g. once in 15 yr) could be practiced to improve no-till systems for agronomic and environmental reasons. We found that SOM, particulate OM, and wet aggregate stability in the surface 2 inches of soil are generally more with long-term continuous no-till than with annual plow-disk tillage. A one-time tillage in continuous no-till did not, however, affect these soil properties supporting a hypothesis that occasional tillage in no-till systems can be conducted
without detrimental effects on soil quality.
The profitability of sorghum production will improve in Nebraska and in eastern Africa through the development and adoption of environmentally sound production practices.
- No publications reported this period