1. Unleashing the power of cassava: new cassava varieties for Africa
Unleashing the power of cassava: new cassava varieties for Africa
Alfred G.O. Dixon et al.
International Institute of Tropical Agriculture (IITA), PMB 5320 Ibadan, Nigeria

2. Africa
Confronted with a rapidly growing population and rising urbanization
Parallel increase in demand for food, feed for livestock, and raw materials for industries

3. Collaborate study of Cassava in Africa (COSCA)
Lessons learnt
Collaborate study of Cassava in Africa (COSCA)
Field production costs (cost of planting materials and field operations’ labor per unit weight of output) declines as yield increases because most of such costs are constant per unit area, irrespective of the yield
Costs per unit weight of output: constant as yield increases, because the processing technique employed is manual with a low level of capital investment
Restricted market opportunities for the final products and expanded production impeded by high cost of production, and product qualities both of which are results of dependence on traditional production and processing technologies
Reliable markets will greatly increase yields of improved varieties of cassava as farmers will pay more attention to their crop
Don’t solve problems alone, capitalize on opportunities

4. Future of Africa’s cassava sub-sector can follow two pathways
Surplus cassava products find no market
Subsistence farming
Very limited adoption and impact of technologies
2. Markets available for surplus cassava products
More of a cash crop
Technologies readily adopted with large impact at producer and consumer levels

5. Production Orientation
Improved cassava varieties responsive to markets will drive down costs of production, harvesting, processing and marketing
Improve the quantity and quality of cassava products for diversified uses
Make cassava products competitive with other raw materials
Production Orientation
Assumes market demand exists for increased production
Entry point for research agenda is prioritization of production constraints
Market Orientation
Market is the driver
No assumption necessary
Entry point for research agenda is the identification of market opportunities

6. Genetic improvement Breeding Paradigm
Developing varieties that are responsive to changing demands
Requires knowledge of producers to consumers’ continuum
Require application of modern science and technology and conventional breeding, as well as increased partnerships
Breeding Paradigm
Phenotype = Genotype x Environment x Crop Management x Policy x Institutions x People

7. Varieties for Africa in the next decade
Gear the crop to more efficient production, postharvest and marketing operations
Attract urban consumers and industries
Create demand for the crop
Stimulate increased production
Provide more income for producers, processors, and traders
WHAT will WE do Today that will MATTER Tomorrow

8. Varieties for the next decade
multiple sources of resistant genes for emerging pest threats for durable resistance
high storage root starch quantity per unit area and time, and quality, for food, feed, and agro-industrial uses
enhanced nutritional content of storage roots (high protein and micronutrient contents)
delayed onset or deactivation of physiological postharvest deterioration (PPD) of storage roots
Acyanogenesis to reduce costs of processing, enhance nutrient bioavalability and or to prevent setback in cassava global market

9. drought resistance as cassava expands to non-traditional areas and in the light of global climate change
nutrient use efficiency
herbicide resistance for durable weed control (e.g. round-up ready resistant cassava)
good plant architecture for ease of mechanized operations and ease of processing
high root and foliage yield (dual purpose cassava) for food and feed

10. Addressing the limitations of the Crop
Bulkiness of edible crop portion and plant propagule which has implications for handling, transport, storage, crop hygiene
Perishability of the edible crop product and plant propagule which has implications for marketing, utilization, and crop management
Low multiplication ratio of plant propagules using standard propagation techniques, which has implications for area planted per unit time

11. Efficiency and effectiveness tools
Shortened breeding cycle and robust seed production methods (e.g. double haploids for rapid production of homozygous lines, pure hybrid seed production, apomixes)
Profuse flowering at will” to access a greater diversity of parental materials
Development of effective molecular markers to optimize the use of genetic resources and in marker-aided introgression/selection
Genotype neutral and efficient transformation and regeneration system
Rapid, and cheap molecular diagnostic tools for important diseases to ensure the safe movement of germplasm
Cheaper and robust rapid multiplication of planting material

12. Location of cassava gene sources
World collection at CIAT = Ca 6000
IITA Collection
Field bank - Manihot esculenta: 3078 accessions with passport data
- In vitro bank = 2300 accessions
National collections = variable numbers
Embrapa collection not already in world collection

13. Different cassava ß-carotene root types
Sources of genes 5 10 15 20 25 36 37 38 39 40 41 42 43 44 45 46 47 48 49
Dry matter percentage
Number of clones
Dry matter distribution among selected genotypes
Delayed PPD in F1 Hybrid of M. walkerae 14 days after harvest
CW 429-1: 0%
Different cassava ß-carotene root types
CM 523-7: 51.9%

14. Potential performance of the top 3 genotypes in various on-station trials in E. Africad
Clone
RTNo a e
F.Yield b
D.Yield c DM
CNP
Rubona, Rwanda
MM96/3733 91
75.5
34.0
45.1
50.8
MM96/5526 97
89.0
33.7
37.9
95.0
MM96/3318
137
67.5
28.9
42.9
70.6
Serere, Uganda
MM96/5373 85
58.4
24.1
41.3
141.0
MM96/1642 75
55.9
22.7
42.0
189.0
MM96/2649 90
59.3
21.6
36.4
227.0
Alupe, Kenya
Just wished farmers get these yields on their farms
MM96/5280
132
217.2 – – –
MM96/1871 98
194.0 – – –
MM96/7151 92
191.6 – – –
Mtwapa, Kenya
LL97/0604
143
50.7 – – –
LL97/0290
137
41.8 – – –
LL97/0727
135
36.0 – – –
aNumber of storage roots/plot; bFresh storage root yield (t/ha); cDry storage root yield (t/ha); dPercentage dry matter; eCynogenic potential (mg HCN eq./dry weight of storage root).

15. Technology will go nowhere without the markets
Re-think what helps the poor most

16. Thank you