Recombination DNA Technology (Nucleic Acid Hybridization )
RTB-led International Alliance for Banana Bunchy Top Disease Control in Africa: Progress and Prospects
1. RTB-led international alliance for banana
bunchy top disease control in Africa:
progress and prospects
Lava Kumar, Charles Staver &
the Alliance Team
www.bbtvalliance.org
RTB Annual Meeting, 8 Dec 2015, Lima, Peru
2. Project team
Lava Kumar, R. Hanna, H.
Kirscht, Nkengla Lilian Wopong,
A Adediji, S Ngatat
IITA, Nigeria and Cameroon
Charles Staver, Bonaventure
Omondi Aman, A Rietveld, S.
Ajambo, G. Blomme
Bioversity International, Uganda and France
M-L. Iskra-Caruana CIRAD , France
C. Niyongere
Institut des Sciences Agronomiques du Burundi (ISABU),
Burundi
M. Soko Bvumbwe Research Station, Malawi
P. Mobambo, GH Vangu Université de Kinshasa, Kinshasa, and INERA DRC
B. Dhed’a Djailo and B Ibadna Université de Kisangani, Kisangani, DRC
M. Z-Tachin and C. C. Tossou
Université d’Abomey-Calavi and INRAB, Republic of
Benin
C. Onyeani, Ogunfunmilayo and
S. Akinyemi
Nigerian Agricultural Quarantine Services and National
Institute of Horticultural Research, Nigeria
AC Mvila
Institut National de Recherche Agronomique, Congo
Brazzaville
M. Andeime
l'Institut de Recherches Agronomiques et Forestières
(IRAF), Gabon
Male to Female ratio 2.2 : 1
3. Outline
Introduction to problem
Strategy
Overview of achievements
Seed multiplication and seed flow management
Gender study
Diagnostics
Virus & vector diversity
Host resistance
Surveillance
Communications and advocacy
Next steps
Conclusions
4. Key points
1. BBTV is an important threat to banana and plantain production
2. RTB initiative is the first major effort to control BBTD in SSA.
3. Galvanized stakeholders across sub-Saharan Africa to adopt a
unified approach to tackle BBTD - ALLIANCE approach
4. Adopted interdisciplinary approach
(virology, entomology, propagation, epidemiology, extension and
social sciences)
5. Developed practicable model, tools and procedures for
containment and recovery of banana production.
6. Capacity development through implementation by partners
7. Communication and advocacy is helping additional funds to
upscale Alliance program.
11. Before 1960s
Since 1980s
Since 1990s
Since 2008
Since 2011
Since 2012
DRC
Angola
Zambia
Nigeria
Central African
Republic
Benin
Gabon
Egypt
Burundi
Rwanda
Equatorial
Guinea
Since 1920s
• BBTV is an introduced
disease in Africa
• Two separate events of
introduction into Africa
• One event of introduction
in central SSA expanded
to 13 countries
• Threatening 35% of Musa
production in Africa
Bunchy top spread in Africa
12. Quantitative data on yield losses not available
“Production declined from truck load to cycle load”
0
2
4
6
8
Total production
area
In BBTV affected
countries
35%
ha(x106)
• Mean incidence of 5% in BBTD
affected countries in SSA
translate to ~100,000 ha.
• Average yield per ha is 7.6 tons
• 760,000 tons of production loss
in SSA due to BBTD (net value
~320 million US$)
13. BBTD control: RTB leading the way in Africa
•Host resistance offers simple and effective solution
but not available
•Integrated and interdisciplinary model developed to contain
BBTD and recover banana production
BBTD containment
and recovery: Building
capacity and piloting
field recovery
approaches through a
learning alliance
•Planning grant awarded in 2012
•Project commissioned in 2013 for 3 years
(2013-15)
•Inception in 2014
•Benin, Burundi, Cameroon, Congo
Brazzaville, DR Congo, Gabon, Malawi
and Nigeria
•Partners: 12 NARES & NPPOs, 3
Universities
14. • Disease spreading through movement of planting material (aphid
vectors contributing local spread)
• Lack of awareness about the disease (inconspicuous symptoms at
early stage / disguise attention)
• High inoculum presence in endemic areas
• Lack of clean planting material
1. WA1 – Benin
2. WA2 – Nigeria
3. CA1 – Cameroon / Gabon
4. CA2 – Congo Republic
5. CA3 – DRC-Bas Congo
6. ECA1 – DRC - Kisangani
7. ECA 2 – Burundi
8. SA1 - Malawi
Challenges
BBTD is
widespread
(endemic)
BBTD is
localized
(emerging)
15. • Pilot integrated community approaches for
recovering banana production
• Establish strategies to ensure low-
cost, healthy planting material production
• Understanding disease
epidemiology, farming systems for
effective containment and recovery
• Develop tools for disease surveillance and
monitoring recovery
1. WA1 – Benin
2. WA2 – Nigeria
3. CA1 – Cameroon / Gabon
4. CA2 – Congo Republic
5. CA3 – DRC-Bas Congo
6. ECA1 – DRC - Kisangani
7. ECA 2 – Burundi
8. SA1 - Malawi
Alliance framework
17. Seed multiplication
Before intervention After intervention
•Mapping disease farms
•Gaining farmer consent
•Eradication of infected plants
•Replanting healthy planting material
•Isolation distance of at least 50 m
Nkhota-kota site in Malawi
18. Understanding gender relations in banana
cropping systems
Gender Division of Labour (GDoL)
• Land clearing: Mostly men (Burundi 64%)
• Weeding: Mostly women (DRC 87%)
Knowledge of BBTD
• Very low among both men and women
• In Gabon over 80% men and women not able to
accurately identify BBTD
Cross-sectional study carried out by gender
specialists using standard protocol in all pilot sites
Access, Use and Control of Productive
Resources
•Land ownership: Mostly men (56%) while land
use is mostly joint (83%)
19. Status of the BBTD gender and social
studies in Pilot sites
Pilot Site CG Centre Data collection Data Analysis Partners
Cameroon IITA Completed:
• 149 surveys
• 15 FGDs and KI interviews
Complete -University of Yaoundé
-University of Dschang
Gabon IITA Completed:
• 57 surveys
• 15 FGDs and KI interviews
On- going -University of Omar Bongo
-Projet de Developpement et Rural,
(PDAR), Gabon
Nigeria IITA Completed:
• 150 surveys
• 15 FGDs and KI interviews
Complete -University of Ibadan
Benin IITA Completed
• 168 surveys
• 10 FGDs and KI interviews
On- going -University of Ketou
Malawi Bioversity Completed for one site:
• 167 surveys
• 4 FGDs and KI interviews
Partially
complete(complete for one
site)
-University of Mzuzu
Burundi Bioversity Pending-security situation :
• 221 surveys
• FGDs and KI interviews-
pending
Complete University of Burundi
Kinshasa Bioversity Completed:
• 108 surveys
• 20 FGDS and KI interviews
Complete University of Kinshasa
Kisangani Bioversity Completed:
• 200 surveys
• 20 FGDs and KI interviews
On- going University of Kisangani
Congo
Brazzaville
CIRAD/ In 2016 - -
20. Diagnostics for BBTV detection
1 2 3 4 5 6 D H B W
ELISA PCR LAMP Real Time PCR
1= 1:101 dilution + + nt nt
2 = 1:102 dilution + + nt nt
3 = 1:103 dilution - + + +
4 = 1:104 dilution - + + +
5 = 1:105 dilution - - + +
6 = 1:106 dilution - - + +
7= 1:107 dilution - - + +
D = Diseased control
B= Buffer control
H = Healthy control
W= Water control
M 1 2 3 4 5 6 7 H B
M 1 2 3 4 5 6 7 H B
A
B
PCR LAMP [New] Real time PCR (TaqMan probe) [New]
ELISA
21. •Understanding selection pressure and
recombination events
•Within a plant
•Within a field
•Within a location
•Within the country
•Characterizing all the six segments of
BBTV genome in each target country
BBTV-C-BENIN
BBTV-C-Idologun43
BBTV-C-Ibola5
BBTV-C-Mende76
JQ820463|BBTV-Rwanda-138
JQ820469|BBTV-Rwanda-142
JQ820457|BBTV-Malawi-73
JN250597|BBTV-SriLanka-Kandy
JF957681|BBTV-Tonga-310
FJ609643|BBTV-India-Bihar
AM418564|BBTV-Pakistan-CL-IM
JF957684|BBTV-Tonga-S28
HQ378193|BBTV-China-Haikou4
68
47
98
66
67
88
63
54
35
55
0.002
C-gene
BBTV-SCP-Mende62
BBTV-SCP-Mende76
BBTV-SCP-BENIN2
BBTV-SCP-Ibola5
BBTV-SCP-BENIN26
BBTV-SCP-Owotedo80
JN250595|BBTV-SriLanka-Kandy
JQ820455|BBTV-Malawi-73
JQ820467|BBTV-Rwanda-142
JQ820461|BBTV-Rwanda-138
AF148943|BBTV-Burundi
JF755981|BBTV-GAB-TV18.2
JF755979|BBTV-CAM-TV14.1
JF755978|BBTV-CAM-TV4.11
JF755986|BBTV-DRC-23
JF755984|BBTV-DRC-TV24
JF755982|BBTV-GAB-TV-17.5
JF755987|BBTV-DRC-25.2
JF755980| BBTV-MAL-TV5.4
FJ605507|BBTV-India-Bihar
FJ859739|BBTV-Pakistan-TA2
JF957660|BBTV-Tonga-S28
HQ378191|BBTV-China-Haikou4
AB108451|BBTV-Japan-JY1100
79
49
99
60
50
55
52
60
63
35
41
54
31
23
51
97
73
0.01
SCP
Understanding BBTV diversity
•97 to 100% identity (very
low diversity)
22. Banana bunchy top disease
NJ Phylogenetic tree
based on the 240 bp
BBTV R (replicase)
gene sequence
Single source of
virus for SSA spread
JQ37549: Benin
JX290301: Nigeria
BBTV Gabon
BBTV DRC
BBTV Malawi
BBTV Zambia
JN204214: Rwanda
BBTV Cameroon
JN204215: DRC
JN204198: Burundi
AY996562: Pakistan
EU140342: India
head office: Egypt
AF416466: Fiji
NC 003479: Australia
AF416467: Tonga
FJ009240: India (Ensete superbum)
KC119098: India (BBTV-Umiam)
AB113659: Vietnam
AF246123: China
AB108458: Japan
AB186926: Indonesia
AB189067: Philippines
AF416468: Taiwan
JX867550: CBDV
EF546813: ABTV
66
69
97
78
64
96
95
99
71
61
83
81
42
51
78
54
14
0.000.020.040.060.080.100.120.14
Clade 2
South-East
Asia (SEA)
Clade 1
Pacific and
Indian Oceans
Group (PIO)
Outgroup
SSA
Sequence divergence
~10% between sub-groups
~5% within sub-groups
23. NJ Phylogenetic tree based on
the Mt COI gene
•Vector populations assessed using
mitochondrial COI gene marker
•Almost exclusive association of
P. nigronervosa with banana in Africa
•P. caladii observed on Alpinia spp.
•How many species are involved in virus
transmission?
Aphid role in BBTV spread
25. Understanding mechanisms of host tolerance
0
5
10
15
20
25
30
35
40
DNA 1 DNA 2 DNA 3 DNA 4 DNA 5 DNA 6 UBQ
Symptomatic
Agbagba
Recovered
Agbagba 1
Recovered
Agbagba 2
Healthy
Control
Ct
Symptomatic
Recovered
plant
• Quantitative PCR to quantify virus titter
• Recovery trait is linked to lowered virus titter
• Potential for exploitation in endemic areas to reduce planting
material replacement rate
26. Understanding mechanisms of host tolerance
BBTV DNA – R
R2= 1
Eff.= 99.66%
0
50000000
10000000
15000000
20000000
25000000
30000000
35000000
40000000
Millioncopies
• Virus titter not necessarily correlates with
symptom severity
•Quantitative PCR
for titter estimation
•BBTV DNA-R gene
29. Boost to ALLIANCE approach
TCP/SFC/3503 :
Appui à la prévention et la gestion de la Maladie de
Bunchy Top du Bananier (BBTD) (2015-17)
Cameroun, Gabon and Equatoriale Guinée
Similar program for
Benin, Malawi and Nigeria in
pipeline
19 - 23 October 2015
30. Linkages and Clusters
Seed degeneration project:
Effect of BBTV on degeneration on
planting material (Farmer practices
vs. positive selection)
Seed system framework:
Effective model for generating
healthy planting material for disease
control in endemic areas
RTB Cluster:
BA 2 (Viral): Improving the livelihoods of smallholder banana producers in
Asia and Africa through recovery and containment of banana bunchy top
disease
31. Conclusions
1. Evidence of disease expansion in West Africa
2. Multifaceted tactics required to contain and recover production in
BBTD affected areas
3. Supply of clean planting material is a key to motivate farmers to
participate in the control efforts
4. Success of the eradication depends on sponsored programs
5. New knowledge on genotype x virus interactions offering a hope
for selection of ‘tolerant clones’ for use in endemic areas and
even breeding
• RTB initiative contributed to a model, tools, procedures and
partnerships for BBTD control in Africa.
• There is a need to continue this momentum and expand to other
countries not included in this phase