Swedish University of Agricultural Sciences www.slu.se

Evaluating OM dynamics, soybean production, value-addition and

Striga weed suppression in ISFM systems –

towards improved productivity, sustainability, and

livelihoods of smallholder farmers in Kenya and Uganda

Kristina Röing de Nowina Bernard Vanlauwe

SLU/CIAT-TSBF/IITA

Swedish University of Agricultural Sciences www.slu.se

Drawing: Miriam Larsson

Swedish University of Agricultural Sciences www.slu.se

c. 20% of maize area in Africa infested Estimated loss in harvest in Africa worth 7 Billion USD/yr

Swedish University of Agricultural Sciences www.slu.se

Justification • Soybean improves soil fertility and farmer livelihoods

through its N fixation capacity, organic inputs, nutritional benefits, and marketing potential. Soybean can also reduce the Striga weed seed bank through suicidal Striga germination.

• Improving soil C stocks through organic matter management enhances soil fertility and crop productivity. Options for soil fertility amendment also include organic resources of varying biochemical quality and bio-char, where C is added to the soil in a more stable form.

Swedish University of Agricultural Sciences www.slu.se

Map of Kenya. Arrows indicate areas of project activities

Swedish University of Agricultural Sciences www.slu.se

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The science; Biochar - effects on soil and yields

Terra Preta soils in the Amazonas are highly fertile soils with high content of inert, ”black” carbon.

How could this apply to Africa?

Maize grown in plots in C Kenya with biochar and fertilizer (left), control (center) and biochar only (right).

Field trials in Western and Central Kenya since 2006; • Yields monitored • Soil and plant properties analysed • Organic matter decomposition/modelling studied • DNA technologies for assessment of soil microfauna used.

Sustained good yields where biochar has been applied.

Swedish University of Agricultural Sciences www.slu.se

The science; Soil fertility and Striga

Striga hermonthica, a parasitic weed, is a major problem in Africa.

Can soybean (Glycine max) be used to combat Striga while improving soil fertility?

The project is based on experiences from AATF, KARI, ICIPE and others. Activities were undertaken in collaboration with CIAT-TSBF/IITA.

Includes field trials and participatory approaches in Western Kenya to study consequences of Striga. Soybean varieties will be tested for effect on Striga reduction and soil fertility improvement. BSc and MSc students have been involved.

Maize field in W Kenya with severe infestation of Striga hermonthica.

Swedish University of Agricultural Sciences www.slu.se

Relationship between farm management, soil health and Striga

• Farm management assessed – in 300+ farms in 6 districts (Vihiga, Siaya, Bondo, Teso, Kisumu, Busia)

• KAP study (Knowledge, attitude and practices) – In 100+ farms in 3 districs

• Field trials: – effect of improved maize varieties and fertilizer on maize productivity and Striga germination

20 trials LR 2011 in 2 districts (Siaya, Bondo) 30 trials; SR 2011; 6 districts (Vihiga, Siaya, Bondo, Kisumu, Teso, Busia) 30 trials; LR 2012 6 districts (Vihiga, Siaya, Bondo, Kisumu, Teso, Busia)

• Field trials: – effect of different varieties of soyabean on striga weed suppression

30 trials SR 2011 in 4 districts SR 2011(Vihiga, Siaya, Teso, Busia) 30 trials LR 2011 in 4 districts SR 2011(Vihiga, Siaya, Teso, Busia)

Swedish University of Agricultural Sciences www.slu.se

Partners and links

• CIAT-TSBF/IITA (Bernard Vanlauwe) – AfNet (Saidou Koala)

• Links to

– Moi University, Kenya – Nairobi University, Kenya – AGRA – N2Africa – AfSIS

Swedish University of Agricultural Sciences www.slu.se

Project Outcomes

• Potential increased collaboration with IITA – Kristina Röing de Nowina Coordinator of Proposal Development at

IITA as of January 1, 2013.

• Sida/VR-funded project 2013-2015 on biochar in relation to biomass, soil and energy – Collaboration between IITA and SLU

• Discussions on an Africa Ministerial Meeting on Integrated Soil Fertility Management – IITA involved in leading this initiative and initial plans have been

discussed with AfNet, AGRA, IFAD, FAO, AU and AfDB.

Swedish University of Agricultural Sciences www.slu.se

Thanks to all farmers, staff, partners, collaborators and

students!