P. Njau, R. Wanyera, S. Bhavani, L. Karani, M. Gethi

1. Breeding
for
rust
resistance
in
Kenya:
Successes,
setbacks
and
future
approaches
P.Njau, R. Wanyera, S. Bhavani, L. Karani and
M. Gethi
njaupnn@yahoo.com

2. • “Ug99”
–
first
reported
in
Uganda
1998/9.
• Muta9ng
and
migra9ng
(2012:
8
races
iden9fied
in
group,
present
in
11
countries)
• Race
TTKSK
(original
“Ug99”
[red])
only
predominates
in
Ethiopia
• Other
Ug99
race
group
races
predominate
e.g.,
Sr24
variants
in
Kenya
Ug99
a
challenging
race
to
beat

3. The
cri9cal
screening
facility
in
Njoro
1. 12
Hectares
of
land
available
for
screening
2. Irriga9on
facility
3. Greenhouse
underway
4. Trained
personnel
5. Room
for
expansion
available
• Over
300,000
accessions
have
been
evaluated
so
far
• Ability
to
evaluate
50,000
accessions
every
year
• Winter
wheat
are
vernalized
and
screened
in
the
field

4. Breeding
for
Resistance
New
mutants
of
the
Ug99
race
easily
overcome
the
deployed
genes
as
was
experienced
in
2007
Na9onal
Breeding
Programme
plays
an
important
role
in
incorpora9ng
the
resistant
gene
in
the
commercial
varie9es

5. Mexico (Cd. Obregon-Toluca/El Batan)- Kenya International Shuttle
Breeding:
a five-year breeding cycle)
Cd. Obregón 39 masl
High yield (irrigated), Water-use
efficiency, Heat tolerance, Leaf rust, stem
rust (not Ug99)
Toluca 2640
masl
Yellow rust
Septoria tritici
Fusarium
Zero tillage
El Batán 2249
masl
Leaf rust,
Fusarium
Njoro, Kenya 2185
masl
Stem rust (Ug99
group)
Yellow rust
● F1 and F1top/backcross developed at CIMMYT, and
advanced to F2.
● F3 and F4/F5 evaluated in Njoro.
● Advanced F6 and initial observation in Mexico
● Observation and selection in Njoro where lines with
suitable adaptation are retained

6. Varie9es
developed
Commercial
Name
Pedigree
Kenya Wren
THELIN # 2/TUKURU
Robin
BABAX/LR42//BABAX*2/3/TUKURU
Kenya Tai
ND643/2*WBLL1
Kenya Sunbird
ND643/2*WBLL1
Eagle10
EMB 16/CBRD//CBRD
Kenya Korongo
BABAX/LR42//BABAX*2/4/SNI/TRAP#1/3/KAUZ*2/TRAP//
KAUZ
Kenya Kingbird
TAM200/TUI/6/PVN//CAR422/ANA/5/BOW/CROW//BUC/
PVN/3/YR/4/TRAP#1
Kenya Hawk12
URES/JUN//KAUZ/3/BABAX/4/TILHI

7. The
Seed
System
and
seed
produc9on

8. Our
focus
• In
future,
breeding
for
rust
resistance
will
focus
on
combining
both
major
and
minor
genes
for
maximum
protec9on
and
durability.
• The
use
of
molecular
markers
to
increase
efficiency
will
aid
selec9on
of
complex
resistances.
• KARI
is
collabora9ng
with
CIMMYT
and
Na9onal
Ins9tute
of
Agricultural
Botany
(NIAB)
in
a
BBSRC
funded
project
to
improve
molecular
laboratory
facili9es
in
Kenya
so
as
to
implement
marker
assisted
breeding
strategies

9. Training
and
capacity
building
Training
course
organized
at
KARI
every
year
under
the
DRRW
project
are
designed
to
train
wheat
breeders
from
public
and
private
sector
in
Africa,
the
Middle
East
and
Central
and
South
Asia,
who
wish
to
learn
about
stem
rust,
evalua9on
of
germplasm,
and
standardiza9on
of
note
taking,
as
well
as
to
update
themselves
with
the
global
knowledge
and
innova9ve
techniques
that
can
enhance
progress
and
efficiency
in
their
breeding
ac9vi9es.

10. This work is funded by the BMGF through Cornel
University under the DRRW project
Need
to
play
a
regional
role
• Training
• Breeding/selec9on
• Breeder
seed
and
cer9fied
seed
produc9on
and
distribu9on
• Screening
of
regional
advanced
wheat
lines