Presentation delivered at the CIALCA international conference 'Challenges and Opportunities to the agricultural intensification of the humid highland systems of sub-Saharan Africa'. Kigali, Rwanda, October 24-27 2011.

1. Mitigating the impact
of biotic constraints
to build resilient banana
systems
in Central and Eastern Africa
Rony Swennen

2. Guy Blomme, Pascale Lepoint, Eldad Karamura,
Piet van Asten, Emmanuel Njukwe, Jim Lorenzen
2

3. Setting the scene
A story from planting till harvest
What’s next?
3

4. Black Sigatoka
4

5. Breeding
Yield increase 225%
5

6. 6

7. The pathogen can adapt: Black resistance breakdown
7

8. 8

9. Influence of farming system on black Sigatoka
Farming system Youngest % Leaf area
leaf spotted with symptoms
Field 4.9 22.2
Homestead 6.9 17.1
LSD* (0.05) 0.9 2.1
9

10. Host response and Yield of plantain
under different management practices
Cultural Youngest leaf % Leaf area with Yield (t/ha)
Practice spotted symptoms
Control 5.5 a 19.6 d 15.8 a
Vigna unguiculata 7.5 b 10.3 c 18.3 a
N-P-K 8.1 b 6.9 b 21.7 b
Wood sawdust 9.3 c 4.2 a 25.0 c
Rice husk 10.9 d 3.8 a 29.2 d
10

11. Different infestation with
a different soil fertility
11

12. The plant-disease/pest complex
12

13. CIALCA characterization study
13

14. G X E: warrants multilocational testing
14

15. Setting the scene
A story from planting till harvest
What’s next?
15

16. Planting:
3 different starts
16

17. Planting
17

18. Cleaning of suckers
18

19. 19

20. Planting
20

21. Banana bunchy top
21

22. Fusarium oxysporum f.sp. cubense (Foc)
22
Healthy sucker???

23. Different densities
23

24. Different densities
Increased soil temperature
with effects on nematodes
24

25. Banana streak virus
All bananas carry the virus genome,
Need to avoid stress Good agronomy
25

26. Host response and Yield of plantain
under different management practices
Cultural Youngest leaf % Leaf area with Yield (t/ha)
Practice spotted symptoms
Control 5.5 a 19.6 d 15.8 a
Vigna unguiculata 7.5 b 10.3 c 18.3 a
N-P-K 8.1 b 6.9 b 21.7 b
Wood sawdust 9.3 c 4.2 a 25.0 c
Rice husk 10.9 d 3.8 a 29.2 d
26

27. Host response and Yield of plantain
under different management practices
Cultural Youngest leaf % Leaf area with Yield (t/ha)
Practice spotted symptoms
Control 5.5 a 19.6 d 15.8 a
Vigna unguiculata 7.5 b 10.3 c 18.3 a
N-P-K 8.1 b 6.9 b 21.7 b
Wood sawdust 9.3 c 4.2 a 25.0 c
Rice husk 10.9 d 3.8 a 29.2 d
Soil cover
27

28. Intercrops
with cocoyam
with climbing beans
28

29. With sweet potato???
29

30. Sucker thinning
30

31. Banana Xanthomonas wilt
31

32. High mat and weevils
32

33. Weevil trapping
33

34. BXW and weevils
34

35. BXW and Sigatoka control
BXW and matooke consumption
35

36. Setting the scene
A story from planting till harvest
What’s next?
36

37. Improved banana germplasm
NSH 20 and NSH 42
FHIA 23 and FHIA 17 37

38. In vitro culture
38

39. Macropropagation
need to get certified healthy
planting material
39

40. Improving productivity
Training on recognition, prevention, and resolving pest and disease
problems in bananas
40

41. Selection criteria of farmers for
banana varieties
Criterion PC1 PC2
Bunch size 0.09 0.44
-0.02
Drought tolerance 0.46
-0.01
Marginal-soil 0.58
tolerance
Availability 0.18 0.32
Taste 0.01 0.41
Maturation 0.05 0.41
Market 0.02 0.43
Longevity 0.60 0.02
= sustainability
Pest tolerance -0.02 0.30
Toppling -0.23 0.24
Eigen Value 2.2 2.0
Total Variation % 22 20 41

42. Mitigating the impact
of biotic constraints
to build resilient banana
systems
in Central and Eastern Africa
Rony Swennen