Breeding of indigenous plants for
Southern Africa:
Domestication of Marama bean
Percy CHIMWAMUROMBE
DEPARTMENT OF BIOLOGICAL SCIENCES
Faculty of Science
UNIVERSITY OF NAMIBIA
pchimwa@unam.na
UNAM
Faculty of Science
2
Outline of Presentation
1. Introduction to Marama bean.
2. Marama bean
domestication/breeding program.
3. Setting up a
domestication/breeding program
4. Summary of past and ongoing
actions.
3
Tylosema esculentum
Marama bean (2n=44) :
Family Fabaceae, subfamily
Caesalpinoidae
Creeping perennial non nodulating
legume (25-36m²)
Edible seeds (3g) and large roots
(25kg-100kg)
Grows in the Kalahari sands regions
(Namibia, RSA & Botswana)
Grows well in low rainfall ( 50-500mm)
Drought avoiding plant
High protein, fatty acids and starch
4
Marama bean life cycle
5
6
Edible Marama bean seeds- 3g per seed
7
8
Marama young roots (bulged)
9
Marama large root, rich in edible and industrial starch
10
Domestication: is the outcome of a selection process that leads to increased
adaptation of plants and animals to cultivation or rearing and utilization by
humans considering the positive or negative role of microorganisms
microbes
microbes
microbes
11
The Performance Gap in Agriculture
100
pgA
80
60
40
20
0
a
A
12
Modern Crop
Domestication and
Breeding:
Southern Africa Context
13
Summary of the Projected impacts of
climate change in Africa
1. By 2020, between 75 and 250 million people in Africa are
projected to be exposed to increased water stress due to
climate change.
2. By 2020, in some countries, yields from rain-fed agriculture
could be reduced by up to 50%. Agricultural production,
including access to food, in many African countries is
projected to be severely compromised. This would further
adversely affect food security and exacerbate malnutrition.
3. Towards the end of the 21st century, projected sea level rise
will affect low-lying coastal areas with large populations.
4. By 2080, an increase of 5 to 8% of arid and semi-arid land in
Africa is projected under a range of climate scenarios.
5. The cost of adaptation could amount to at least 5 to 10% of
14
Gross Domestic Product (GDP).
Source: Report. Summary for Policy Makers, IPCC, 2007
50 yr Climate Change projections
Tylosema genus distribution
15
African Child Wellness Statistics
1. It has been estimated that every minute eight under-five children die in
sub-Saharan Africa.
2. Two thirds of the under-five deaths in the African Region are due to
preventable causes. The chief causes of death are complicated by
malnutrition that accounts for one third of all deaths in children under
five years.
3. Food insecurity in Africa threatens the lives of millions of vulnerable
people.
4. Under nutrition is directly or indirectly responsible for 3.5 million child
death every year.
5. Sub-Saharan Africa has one of the highest prevalence of low birth
weight ranging from 7-42%.
6. Although the degree to which indirect determinants of death are
expressed varies between countries, malnutrition is a critical risk
factor in most countries, and nutrition and food security remains a
fundamental challenge to child survival.
16
Source: Report. WHO Regional Office for Africa, 2012
What are the Southern African
regional common issues?
•
•
•
•
Food production-Climate change effects
Health issues
Nutritional issues (child protein deficiencies)
Jobs (and jobs creation)
17
Modern Crop Domestication
1.
2.
3.
4.
5.
6.
7.
8.
An open-minded approach is required, even hearing brutal non conventional
ideas.
Prioritize participatory approaches until better empowerment tools come.
Mixing past practices and new styles in domestication- learning from the current
and past experiences invoking new ways.
Consider the current, past nutritional trends (e.g. most people nowadays
remove chicken skins, running away from fats, this is a new trend. It was not like
this 30 years ago). Now is a there is need to breed for lean chicken!
Consider climate change effects.
New mindset: develop indigenous crops (just looks at what Africa eats today,
and ask how much of that is native to Africa, only 3-4 crops only, there rest of
them are invasives, for lack of better word).
This is time to develop local crops that resilient and adapted to local
environments for millennia, may be we can combat climate change effects.
In many fora where health issues of Africa are discussed one always hear that
people should start eating traditional foods to avoid exposure to
modern/western/eastern foods which their physiology is not genetically adapted
to. Whether true or false, real of perception, these voices need to be listened
and something must be done, lest the future generations will not have kind
words to us.
NOTE
1. Time is limited.
2. So be fast, move away from
BUSINESS
AS-USUAL
(BAU)
domestication
approaches.
19
Central Goal:
v
Domestication
of
Marama bean
1.Basic Plant
Biology
Central goal:
v
domestication
of
Marama bean
1.Basic Plant
Biology
Central goal:
v
domestication
of
Marama bean
2. Crop
breeding
1.Basic Plant
Biology
Central goal:
v
domestication
of
Marama bean
3. Crop protection
2. Crop
breeding
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
4. Product development
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
4. Product development
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
4. Product development
6. Product piloting
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
4. Product development
6. Product piloting
8. Conservation Genetics
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
4. Product development
6. Product piloting
9. Omics and gene discovery
8. Conservation Genetics
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
4. Product development
6. Product piloting
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
4. Product development
6. Product piloting
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
4. Product development
6. Product piloting
11. Participatory product piloting
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
12. Bio-fertlisers
4. Product development
6. Product piloting
11. Participatory product piloting
13.More gene discovery
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
12. Bio-fertlisers
4. Product development
6. Product piloting
11. Participatory product piloting
13.More gene discovery
14. Commercial scales of production
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
12. Bio-fertlisers
4. Product development
6. Product piloting
11. Participatory product piloting
13.More gene discovery
14. Commercial scales of production
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
12. Bio-fertlisers
4. Product development
6. Product piloting
11. Participatory product piloting
15. Commercial scales for byproducts
13.More gene discovery
14. Commercial scales of production
9. Omics and gene discovery
8. Conservation Genetics
10. Participatory production
5. Agronomy
1.Basic Plant
Biology
2. Crop
breeding
Central goal:
v
domestication
of
Marama bean
3. Crop protection
7. Microbiology& Entomology
12. Bio-fertlisers
16. Future perspectives
4. Product development
6. Product piloting
11. Participatory product piloting
15. Commercial scales for byproducts
Building capacity on crop diversification
in light of climate change:
A broad skills training vehicle.
37
Initial Research Questions
• Is there variability between- and in marama populations?
• Are there any superior genotypes in the environment?
• Can molecular genetic tools be used to identify and selected
such?
• Can phenotypic tools be used for selection?
• Is it possible to increase the yield of marama?
• Do bacteria play a role in enhancing marama nutrient
acquisition?
• Is it possible to prescribe best growing areas and cultural
practices?
• Does marama have other uses besides food and feed: ITK
uses?
• Is marama bean acceptable and viable as a commercial
crop- locally, regionally and internationally?
38
Marama
Distribution Map
T. esculentum
T. humifusum
T. argenteum
T. angolense
T. fassoglense
Genotype variations
Using SSRs, We have found
low inter-population genetic
diversity and high intrapopulation
variability
in
marama subpopulation
The similarities for each
cluster were between 75-92%,
which is high, indicating low
genetic variability.
40
The case for domestication in sA
• Most of the Kalahari concept is in sA, semi desert to
desert
• High value nutrition (Protein, FAs, Starch)
• Low seed production (1-2) seeds/pod) remains a
challenge that can be dealt with plant breeding
• Disappearing accessions is another concern
• Malnutrition high in Southern African can be
addressed by supplemented the protein with local
marama
• Selection of superior accessions important and is on
going
41
• Can be grown on land considered to be waste land
Rainfall Map of Namibia
42
43
44
Value addition: development of
Marama prototype products
•
Namibia, South Africa, Botswana
– Roasted marama bean nuts
– Green marama
– Full fat and defatted marama bean flours with
various confectionery uses
– Marama-sorghum composite meals to be used
for preparation of porridge
– Marama milk
– Marama oil
Cosmetics
Pharmeutics
Starch
45
46
Isolation and characterization of the starch of
marama bean young roots in terms of its physical &
chemical and pasting properties.
Marama amylose (35.74%)
Cassava amylose (18 -28%,)
Sweet potato amylose (28%),
47
Marama AGPL
Phaseolus vulgaris
Glycine max
I
Pisium sativum
Lens culinaris
Cluster I
Medicago truncatula
Cicer arietinum
Solanum lycopercium
Solanum tuberosum
II
Arabidopsis thaliana
Zea mays
Brachypodium distachyon
Cluster II
Sorghum bicolor
Escherichia coli
1.
Isolation and molecular characterization of marama starch biosynthetic genes
(SSSI, AGPase & SBEs).
2.
Physicochemical and functional properties of native marama starch finalized. Better
properties than most root starches
3.
Isolation of serine protease inhibitor gene for marama
48
Comparison of total seed protein
content
Legume
% Protein content
Soybean ( some varieties)
38
Marama
32
Lupine
31
Lens
24
Pea
23
Broad bean
23
Phaseolus
22
49
Germplasm Conservation
1. 450 accessions have been collected
2. Community centred in-situ germplasm
conservation
3. Phenotypic selection of desirable
characteristics
50
Marama bean is an obligate outcrosser
Pollination by bumbble bee
51
Germination characteristics
14
12
10
8
6
Number germinated
4
2
0
52
Inter-nodal lengths
53
Gamma irradiation increase
germination rates
54
On-Farm Cultivation Trials in
Namibia
•
•
•
•
•
One farm in Okakarara
4 farms in Epukiro
2 farms in Vaasdraai
90kg-200kg/ha (1.2-2 tonnes/ha potential)
Planned 12 farms in Omaheke region with
NEPAD/SANBIO support
55
Marama
farm
preparation
56
Shortening the Reproductive
Life cycle
• One of the priorities is to shorten
the life cycle. We hypothesize that
marama appears to grow slowly
because in its natural environment
moisture and fertility is restrictive.
57
Pending & Current Activities
1. Molecular Breeding
1.
2.
3.
4.
5.
Genotype identification- molecular makers
Crosses
Genetic maps
Selections
Mutation breeding
2. Field trials
1.
2.
3.
4.
Cultivar trials
Plant-water relationships
Yields evaluations
Seed quality evaluations (populations and individuals)
3. Molecular Studies
1. Libraries
2. Gene discoveries
4.Plant-Microbe interactions
5. QTLs and Drought avoidance
6. Heat Stress tolerance
58
Bacteria in the rhizosphere of Tylosema
esculentum (Marama bean): Possible role in
nitrogen fixation and growth enhancement
1. Does marama, in its developmental stages,
harbour tissue specific advantegous
endophytic microorganism communities?
2. What are the identities of the active
endophytic diazotrophs associated with
marama with respect to tissue and
developmental stages?
59
So far
Bacteria isolations from
germinated gnotobiotically
grown seedlings have started.
60
We now know that marama bean seeds
are home to at least:
1. 34 culturable bacterial species from
• 16
genera
including
Bacillus,
Rhizobia,
Curtobacterium,
Pantonea,
Microbacterium,
Enterobacter, and Burkoholderia were isolated.
2. 16 isolates with <95% similarity to published 16SrDNA
sequences are being treated as potential new species
and work is ongoing to characterize and describe them
further.
3. Some of the endophytic bacteria species have strong
characteristics for promoting growth directly on
stimulating the plant and indirectly creating a
permissive environment for growth.
61
Marama plant growth promoting bacteria and mycorrhiza
• We observed IAA production activity,
ACC deaminase activity, siderophore
forming activity, phosphate solubilizing
activity, endoglucanase production and
AHL production activity and nitrogen
fixing activity and more.
62
Concluding Remarks
1. Marama farming is possible, conservation
and high production.
2. New biological details on marama are
being unravelled.
3. Microbial-interactions key to its nutrient
provision.
4. The enigma still persist, many unknowns,
however we are closing the gaps: from the
known knowns, known unknowns to the
unknown knowns.
.63
5. Marama bean domestication is WIP.
Acknowledgments
• Marama Research Group at UNAM
• Kirkhouse Trust
• Swedish Development Agency (SIDA)
• CPP initiative on Integrated Sustainable Land
Management
• NRF, South Africa
• MAWF (IPTT)
• UNAM, Namibia
• University of Botswana
• Swedish University of Agricultural Sciences
• University of Pretoria
• University of Bremen
• McGregor Foundation in USA
• TFO (BMBF)
• Alexander von Humboldt Foundation
64
Thank you
pchimwa@unam.na
65