International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing spatial variability
diagnostics at regional scale
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing spatial variability
diagnostics at regional scale
12012014712884Farms (n)
44559Sites (n)
Cycle = the period between subsequent harvests from a single mat. This value is around 1 year at 1200 m.a.s.l. but increases with altitude
Sites = nr. of districts (Uganda) or villages (Rwanda, Burundi, North Kivu, South Kivu)
The top and bottom of the error bars represent the maximum and minimum site average yield per region/country
12012014712884Farms (n)
44559Sites (n)
Cycle = the period between subsequent harvests from a single mat. This value is around 1 year at 1200 m.a.s.l. but increases with altitude
Sites = nr. of districts (Uganda) or villages (Rwanda, Burundi, North Kivu, South Kivu)
The top and bottom of the error bars represent the maximum and minimum site average yield per region/country
0
10
20
30
40
50
60
70
Uganda Rwanda Burundi North Kivu South Kivu
Yie
ld t
ha
-1cycle
-1
0
10
20
30
40
50
60
70
Uganda Rwanda Burundi North Kivu South Kivu
Yie
ld t
ha
-1cycle
-1
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing spatial variability
from Lake Victoria basin to Albertine rift
Central Uganda
15 t/ha/cycle
East Rwanda
East Burundi
SW Uganda
25 t/ha/cycle
1100m 1300-1400m
1600-
2100m
Rusizi
SemlikiKivu
Region
45 t/ha/cycle
Rainfall
Pest and disease pressure
Soil fertility
Plant densities
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Ruhango
Nzenga
Munoli
Lurhala
Luhihi
Kirundo-
Kibuye
Kibungo
Kaliva
Kabam
ba
Gitega-2
Gitega-1
Cyanangu
Cibotoke
Burhale
Bingo
K (
% o
f dry
matt
er)
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
Understanding existing spatial variability
diagnostics at regional scale
Drought major constraint <1200 mm/yr
Soil fertility highly variable, but generally
better near Albertine rift
High foliar K conc = high productive sites
Pest pressure low > 1300m
BBTV and BXW ‘restricted’ to hotspots
Conclusion: abiotic stresses very important
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Yield gap analysis in Uganda
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing spatial variability
diagnostics at village scale
‘Poor’ versus ‘Rich’ farmers:
• Yields
• Arable land
• Hired labor
• Livestock
• External revenues
• Commercialization
Conclusion:
Large differences in access
to resources → technology
choice
PhD thesis ongoing on farmer
innovation in GL region
Poor Medium Rich
Number of farms 17 28 5
Banana performance
Bunch weight 16.2b 16.4b 20.1a
Average spacing (m) 2.2 2.3 2.2
Land, livestock, and labor
Tot. arable land (ha) 0.32b* 0.48b 0.55a
% land und. banana 70 70 70
Hired labor (man/day) 0.5b 0.8b 3.2a
Cows (nr) 0.77 2.2 3.0
Soil Org Carbon (%) 1.3 1.3 1.4
Weevil damage (XT %) 4.0 5.4 4.4
Income sources
Earning salary % 0b 4b 40a
Ext. financial sup. % 24b 50ab 80a
% farms selling ban. 47b 75a 100a
*Letters behind numbers in the same row indicate significant differences (p<0.1)
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing spatial variability
diagnostics at farm scale
Delstanche, van Asten, Gaidashova, Delvaux – Eurosoil conference
MSc thesis I.A. Newton
Most still needs to be published
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing temporal variability
on-farm monitoring study in SW Uganda
150 plants - 10 farms - 2 years
• Peak production May – Oct→ prices are low
• Low production Nov – Feb→ prices are high
Sucker emergence → Harvest date
• Give preference to suckers emerged in Q1 over those that emerged in Q4
• Farmers prefer desuckering in Dec-Jan, but they should then leave the smallest, not the biggest suckers
Got Matooke for Christmas →
Birabwa, van Asten, Newton, Taulya,
Mombasa presentation – to submit to Act Hort
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing cropping systems
Comparing banana-coffee mono and intercrop
APEP-funded project
300 farmer fields in Uganda
• Bananas do not reduce (<13%)
coffee yields, but Robusta
banana yields
• Banana intercrop generates
+ 700 $/ha/yr in Robusta
+ 1900 $/ha/yr in Arabica
van Asten, Mukasa, Uringi
poster Mombasa – Act Hort, to be submitted
R4D review feature story
PhD research on banana-coffee
systems has started in Burundi
under CIALCA-II
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Pushing system components to their boundaries
Drought trials
Pot trials
a. Four cultivars (AAA-EA, AAA, ABB, AB)
b. Three moisture treatments
no stress: pF 1.8 – 2.1
moderate stress: pF 2.5 – 2.7
strong stress: pF 2.8 – 2.9
c. Measure stress (e.g. stomatal conductance)
c. Determine water use efficiency
d. Use findings to validate field results
Interim results: bananas don't look stressed
when they actually are!
Planning field trial in CIALCA-II project
Results from the above not published thus far
Field trial results - Nyombi et al (PhD reseach) in 2009
Rain
fall
(mm
)
0
15
30
45
60
75
90
Dec 2004 June 2005 Dec 2005 June 2006 Dec 2006 June 2007 Dec 2007
2005 - 1206mm
2006 - 1380mm
2007 - 935mm
B
0
15
30
45
60
75
902005 - 1034mm
2006 - 1334mm
2007 - 1633mm
Sept 2004 Mar 2005 Sept 2005 Mar 2006
A
A
Sept 2006 Mar 2007 Sept 2007
Cycle 2
Cycle 1
Cycle 3
Cycle 1
Cycle 2
0.05
0.15
0.25
0.35
0.45
Saturation (pF 0) Field capacity (pF 2) Wilting point (pF 4.2) 0-30 cm 30-60 cm 60-90 cmC
April 2005 Nov 2005 June 2006 Dec 2006 July 2007
0.05
0.15
0.25
0.35
0.45
Saturation (pF 0) Field capacity (pF 2) Wilting point (pF 4.2) 0-30 cm 30-60 cm 60-90 cm
June 2005 Jan 2006 Aug 2006 Feb 2007 Sept 2007
D
Volu
metr
ic m
ois
ture
conte
nt
(m3 m
-3)
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Testing the hypotheses in the field
Nutrient omission trials
1. Setupa. Central and Southwest Uganda
b. N, P, K, Mg, Zn, S, B, Mo
c. Target yield 50 t/ha/yr
2. Preliminary findings after 2-3 cycles
a. K is most deficient
b. Fertilized yields poor (< 30 t/ha/yr)
c. Drought stress is a major problem
d. Ferralsols soils → poor root systems
e. Fertilizer improves sensory quality
0
2000
4000
6000
8000
0 200 400 600 800
K uptake (kg ha-1
)
0N-0P-0K 0N-50P-600K150N-50P-600K 400N-0P-600K
400N-50P-0K 400N-50P-250K400N-50P-600K Max dillutionMax concentration
Banana f
inger
bio
mass (
kg h
a-1
)
FULL
- K
Horizontal distance from center of pseudostem (cm)
Ro
otin
g d
ep
th (
cm
)
-150 -100 -50 0 50 100 150
-100
-50
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Nyombi, van Asten, et al.: Draft ready → submit Feb 2009
Taulya, van Asten, et al: Global plant sci book - submitted
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Testing the hypotheses in the field
Optimal mulch thickness
On-station trial at ISAR, Rwanda
1. 0 cm mulch
2. 5 cm mulch
3. 10 cm mulch
4. 20 cm mulch
With and without shading
Soil moisture monitoring
→ 5 cm already very effective
Soil chemical properties
→ improvement proportional to application
Van Asten, Twagirayezu, Gaidashova
Rwanda Agricultural Conference
Presentation and paper, 2007. Week Number (1 = 9 Sept)
12111098765321
Soil
Mois
ture
Conte
n (
Vol %
)
30
20
10
0
1.00
2.00
3.00
4.0020 cm
10 cm
5 cm
0 cm
Mulch rates
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Testing the hypotheses in the field
Mulch and zero-tillage trials
Setup in CIALCA project
8 researcher-managed trials
in Rwanda, Burundi, and DRC
1. Mulch removal + tillage
2. Self-mulch + no-till
3. Trypsacum + no-till
4. Hyparrhenia + no-till
All intercropped with bush beans
Objectives
• Impact on nutrient stocks and flowsPhD thesis Syldie Bizimana (ISABU - Burundi)
• Impact on soil physics and root systemsPhD thesis Tony Muliele (INERA - DR Congo)
• Impact on banana + bean crop performanceMSc thesis Agnes Mukdandida (ISAR- Rwanda)
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Testing the hypotheses in the field
other field and lab trials
Planting density trials in Rwanda
• from 1000 – 5000 plants/ha
• 3 different cultivars
• 3 contrasting agro-ecologies
• compare with farmer practicesPhD thesis Telesphore Ndabamenye (ISAR-Rwanda)
CIALCA-Bioversity sponsored
Abuscular Mychorrizal Fungi (AMF)
• On-farm diagnostics and pot trials Rwanda
• Diagnostics and field trial in Kenya, Uganda
Mulch x Nematode trial in Rwanda
• Establish yield loss due to P. GoodeyiPhD thesis Svetlana Gaidashova (ISAR-Rwanda)
Collaboration in Kenya with TSBF
AMF research presented in Mombasa conference
Paper on AMF on-farm diagnostics to be submitted
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Crop growth and nutrient response models
Ugandan potential yield – 112 t/ha/yr
Crop growth model based on:
1. Light interception and L.U.E.
2. Temperature sum and biomass partitioning
3. Water limited yield
4. Nutrient (N, P, K) limited yield (QUEFTS)
PhD research of Kenneth Nyombi (Wageningen University)
PARINT
PTRAN
DAvtmp
TRANRF
W lv, g W lv,d
Tbase
dW/dt
Tsum
dTsum/dt(dW/dt) lv,d
(dW/dt) lv
(dW/dt) st
(dW/dt) rt
(dW/dt) su
(dW/dt) bu
W st
W rt
W su
W bu
dGLAI/dt
dDLAI/dt
LAIDTR
TRAN
W co
(dW/dt) co
LUE
KDF
WATER
EXPLOR
EVAPO
W rt,d(dW/dt) rt,d
RAIN
RNINTC
DRAIN
RAIN
RNINTC
RAIN
RNINTC
RAIN
RNINTC
RAIN
RNINTC
RN
PARINT
DTR
SLA
A
CB
+
=
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
On-farm testing of best-bet technologies
the APEP project
APEP demo plots
• application of blanket NPK fertilizer
• 94 demos versus 84 control
• Demos yield 25 – 100%
• MRR > 500% close to Kampala
• MRR < 100% beyond Masaka
Conclusion:
Fertilizer only profitable near Kampala
New fertilizer recommendations
Banana and Coffee taking into account
• nutrient deficiencies (= region)
• target yield (= resource availability)
Van Asten et al., APEP final technical report
Wairegi, van Asten, et al. AFNET conference paper
Van Asten et al., Mombasa presentation, Act Hort
Uganda matooke farm gate bunch price
0
100
200
300
0 50 100 150 200 250 300 350
Distance to Kampala
Bu
nch
p
rice (
US
H/k
g)
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Understanding existing cropping systems
Comparing banana-coffee mono and intercrop
APEP-funded project
300 farmer fields in Uganda
• Bananas do not reduce (<13%)
coffee yields, but Robusta
banana yields
• Banana intercrop generates
+ 700 $/ha/yr in Robusta
+ 1900 $/ha/yr in Arabica
van Asten, Mukasa, Uringi
poster Mombasa – Act Hort, to be submitted
R4D review feature story
PhD research on banana-coffee
systems has started in Burundi
under CIALCA-II
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org
Projected banana-coffee work
Output 4 Capacity &
synergies
Capacity development
Partnerships & training materials
Scientific synergies
Output 3
Socio-economics Strengthen coffee-value chain through:
Determinants for investments
Access to input markets
Output markets (niches)
Organisational structures
Output 1
Crop physiology Effect of banana shade under different levels of water and nutrient stress on:
Coffee yield (quantity, quality)
Photosynthetic capacity
Pest & disease pressure
Trade-off analysis
Plant arrangement recommendations
Output 2
Agronomy Identify and test improved soil and water management technologies
Identify drivers of productivity
Map nutrient deficiencies
Participatory testing
Cost-benefit analysis
Improved soil and water practices
Empowerment of coffee actors
organ plant field farm farm organisation market
IITA NARO
AIT IFPRI
Figure 2: Relational diagram showing the relationship between the research conducted for the four outputs, the spatial level that the research activities primarily target, and the technical backstopping domains of the project research partners.
Strengthening coffee-value chain