Beyond the current NERICAs: better exploitation of

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Beyond the current NERICAs better exploitation
of Oryza glaberrima Steud. Koichi
Futakuchi, Howard Gridley and Moussa SiéAfrica
Rice Center (WARDA) Africa Rice Congress 31
July 4 August 2006, Dar es Salaam, Tanzania
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Current basic concept of the interspecific breedin
g 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)
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Brief history of the interspecific breeding
(for upland) at WARDA 1990 and 1991 Screening
of WARDAs 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 17
numbered. 2005 NERICA number increased up to 18.
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• 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

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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
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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)
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1. Filling a gap between NERICAs and O. glaberrima
1-1 Example of a gap (weed competitiveness)
Current NERICAs
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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
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2. Unutilized characteristics of O. glaberrima
2-1 Multiple resistance of O. glaberrima 2-1-1
Example (CG 14)
Iron toxicity
Seedling vigor
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2. Unutilized characteristics of O. glaberrima
2-1 Multiple resistance of O. glaberrima 2-1-1
Example (CG 14)
(Data from Tobita)
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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
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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
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2. Unutilized characteristics of O. glaberrima
2-2 For higher yield than the O. sativa
parents 2-2-1 Yielding types of current NERICAs
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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
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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 backcros
sing breeding.
(Data from Osiname)
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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 -
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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
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3. Seeking better O. glaberrima
3-2 Example (short duration and early vigor)
IRGC AC 104038
IRGC AC 104038
CG 14
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.
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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
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4. Intra-specific breeding of O. glaberrima
4-2 Drawbacks 4-2-1 Lodging and grain shattering
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4. Intra-specific breeding of O. glaberrima
4-2 Drawbacks 4-2-2 Grain quality
(Watanabe et al., 2002a)
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4. Intra-specific breeding of O. glaberrima
4-2 Drawbacks 4-2-3 Taste (texture)
(Watanabe et al., 2002b)
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4. Intra-specific breeding of O. glaberrima
4-2 Drawbacks? 4-2-4 Yield
(Dingkuhn et al., 1998)
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4. Intra-specific breeding of O. glaberrima
4-2 Drawbacks? 4-2-4 Yield
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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.
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4. Intra-specific breeding of O. glaberrima
4-3 The drawbacks can be remedied?
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4. Intra-specific breeding of O. glaberrima
4-3 The drawbacks can be remedied?
- Much more studies will be needed
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Thank you Merci Asante sana Obrigado Melesi ??????
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