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Beyond the current NERICAs: better exploitation of Oryza glaberrima Steud. Koichi Futakuchi*, Howard Gridley and Moussa Sié Africa Rice Center (WARDA) Africa Rice Congress 31 July – 4 August 2006, Dar es Salaam, Tanzania. Current basic concept of the interspecific breeding at WARDA:
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Beyond the current NERICAs: better exploitation of Oryzaglaberrima Steud. Koichi Futakuchi*, Howard Gridley and Moussa SiéAfrica Rice Center (WARDA) Africa Rice Congress 31 July – 4 August 2006, Dar es Salaam, Tanzania
Current basic concept of the interspecific breeding at WARDA: To develop NERICAs possessing the adaptability of O. glaberrima to local conditions in WCA and the characteristics of O. sativa associated with high yielding (Combination of the resistance of O. glaberrima and the high yield potential of O. sativa)
Brief history of the interspecific breeding (for upland) at WARDA 1990 and 1991: Screening of WARDA’s germplasm collection, O. glaberrima (1130), improved O. sativa (316) and traditional O. sativa (275), in relation to morpho-agronomic characteristics. 1992: Start of crossings between O. glaberrima (8 lines) and O. sativa (5 varieties). 1994: First fixed fertile interspecific progenies. 1996: Start of farmers’ participatory varietal selection (PVS) in CI. 1997: Start of Interspecific Hybridization Project (IHP) 2000: First release of interspecifics (CI and Guinea). 2000: NERICA 1–7 numbered. 2005: NERICA number increased up to 18.
Possible improvement in rice breeding with better • use of O. glaberrima • To fill a gap between existing NERICAs and O. • glaberrima already used in the interspecific breeding • in relation to resistance to local constraints and other • traits (weed competitiveness, high protein etc…) • 2. To exploit characteristics of O. glaberrima which are • not currently focused • 3. To seek better O. glaberrima in relation to important • traits • 4. Intra-specific breeding of O. glaberrima
1. Filling a gap between NERICAs and O. glaberrima 1-1 Example of a gap (weed competitiveness) Ideal plant type of high yielding weed competitive rice
1. Filling a gap between NERICAs and O. glaberrima 1-1 Example of a gap (weed competitiveness) NERICA 1 WAB56-104 (O. sativa) CG 14 (O. glaberrima)
1. Filling a gap between NERICAs and O. glaberrima 1-1 Example of a gap (weed competitiveness) Current NERICAs
1. Filling a gap between NERICAs and O. glaberrima 1-2 How to fill the gaps - No need to change the current basic concept - Conventional breeding by efficient selection with populations of sufficient size - MAS for some traits such as high protein content Prototype of NERICAs with the O. glaberrima-like vegetative growth developed by conventional backcross breeding
CG 14 WAB56-104 NERICA NERICA NERICA Bouake 189 2. Unutilized characteristics of O. glaberrima 2-1 Multiple resistance of O. glaberrima 2-1-1 Example (CG 14) Iron toxicity Seedling vigor
2. Unutilized characteristics of O. glaberrima 2-1 Multiple resistance of O. glaberrima 2-1-1 Example (CG 14) (Data from Tobita)
2. Unutilized characteristics of O. glaberrima 2-1 Multiple resistance of O. glaberrima 2-1-1 Example (CG 14) - Drought resistance (Jones et al., 1997) - Drought recovery (Audebert, personal communication) - Weed competitiveness (early vigor, droopy leaves…) (Jones et al., 1997; and others) - Resistance to nematode (Coyne, 1994) - Adaptability to acid soils (Tobita, unpublished data) - Resistance to water logging (Futakuchi et al., 2001) - Iron toxicity tolerance (Sahrawat and Sika, 2002) - Zinc deficiency tolerance
2. Unutilized characteristics of O. glaberrima 2-1 Multiple resistance of O. glaberrima 2-1-2 How to introduce such a comprehensive trait to NERICAs - MAS? - Conventional breeding by more efficient selection with populations of sufficient size However, more O. glaberrima-like progenies than current NERICAs have to be developed. The number of backcross to the O. sativa should therefore be restricted. - More assistance of biotechnology to overcome the sterility barrier
2. Unutilized characteristics of O. glaberrima 2-2 For higher yield than the O. sativa parents 2-2-1 Yielding types of current NERICAs
2. Unutilized characteristics of O. glaberrima 2-2 For higher yield than the O. sativa parents 2-2-2 New concept New high yielding NERICAs with weed competitiveness
2. Unutilized characteristics of O. glaberrima 2-2 For higher yield than the O. sativa parents 2-2-2 New concept Some prototypes of new NERICAs (WAB1159) are possessing the same size of panicles with current NERICAs and O. sativa and the larger number of panicles than they have. The prototypes were developed by conventional backcrossing breeding. (Data from Osiname)
2. Unutilized characteristics of O. glaberrima 2-2 For higher yield than the O. sativa parents 2-2-3 How to develop such NERICAs - With the new concept - Conventional breeding - …
3. Seeking better O. glaberrima 3-1 Which traits? - Re-screening with traits already checked (and also lines already tested), If improved screening tools have been developed for such traits - Relatively less information is available for resistance of O. glaberrima to lowland constraints than upland ones - Traits, with which little information is available, such as micronutrients - If new germplasm can be available for screening, any important traits for rice cultivation in WCA should be focused
3. Seeking better O. glaberrima 3-2 Example (short duration and early vigor) IRGC AC 104038 CG 14 IRGC AC 104038 CG 14 Seeded on 22/05/06 Seeded on 22/05/06 Seeded on 11/05/06 90% heading on 11/07/06 Seeded on 11/05/06 90% heading on --/08/06 Ref. The 90% heading date of NERICA 8 (seeded on 11/05/06) was 17/07/06.
4. Intra-specific breeding of O. glaberrima 4-1 Advantages - Intra-specific breeding of O. glaberrima will be the best way to exploit its assets such as multiple resistance to major constraints in WCA and high protein content etc…
4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks 4-2-1 Lodging and grain shattering
4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks 4-2-2 Grain quality (Watanabe et al., 2002a)
4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks 4-2-3 Taste (texture) (Watanabe et al., 2002b)
4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks? 4-2-4 Yield (Dingkuhn et al., 1998)
12 WAB56-104 10 ( O. sativa ) 8 CG 14 Frequency (%) 6 (O. glaberrima) 4 Bouake 189 ( O. sativa ) 2 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 6.5 7.0 7.5 8.0 Yield (t/ha) Yield of NERICAs (WAB450 series) in irrigated lowland in DS 4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks? 4-2-4 Yield
4. Intra-specific breeding of O. glaberrima 4-2 Drawbacks 4-2-5 Summary - Grain shattering - Lodging which accelerates grain shattering and ruins grain quality - Unacceptable grain quality at market (red rice, low whiteness and high breakage in milled rice) - Difficulty to develop lines with a range of texture meet to various preferences of people in WCA However, lines with an acceptable yield level can be developed.
4. Intra-specific breeding of O. glaberrima 4-3 The drawbacks can be remedied?
4. Intra-specific breeding of O. glaberrima 4-3 The drawbacks can be remedied? - Much more studies will be needed…
Thank you Merci Asante sana Obrigado Melesi ありがとうございます