The performance of CIMMYT wheat germplasm in East Africa

with special emphasis on Ethiopia

INTRODUCTION

Ethiopia is the largest producer of wheat in sub-Saharan Africa. Wheat occupies about 1.8 million

hectares annually and ranks 4th in area and 2nd in productivity among the cereals (CSA, 2010).

Bread wheat (Triticum aestivum L. em. Thell.) and durum wheat (T. turgidum var. durum Desf.) are

the major types of wheat grown. Bread wheat was introduced to Ethiopia more than eight decades

ago while durum wheat was indigenous to the country which is considered the secondary center of

diversity for tetraploid wheat (Hailu, 1991; Solomon et al., 1995). CIMMYT and ICARDA have

the largest collection of wheat accessions (i.e. 150,000) in the world which serves as a major source

of germplasm for national programs in developing countries. Currently, CIMMYT distributes over

5000 new genetically diverse wheat genotypes targeting the different environments of Ethiopia

through its international nurseries. Introductions are valuable sources of germplasm in the country.

Their continuous assessment against major diseases is necessary because of the frequent changes in

pathogen races and virulences (Johnson, 1988). The objective of this paper is to asses CIMMYT’s

germplasm for their adaptation, yield performance, disease resistance and stress tolerance under

diverse environments in Ethiopia

B. Abeyo1*, H. Braun2, R. Singh2, K. Ammar2, T. Payne2, A. Badebo3, F. Eticha3, B. Girma3, and S. Gelalcha 3

1CIMMYT-Wheat Program, P.O. Box 5689, Addis Ababa, Ethiopia

2CIMMYT Wheat program, Apdo Postal 6-641, 06600 Mexico D.F., Mexico

3Ethiopian Institute of Agricultural Research , P.O. Box 32, Addis Ababa , Ethiopia

*Corresponding author: b.abeyo@cgiar.org

MATERIALS and METHODS

Germplasm Source: CIMMYT is the major sources of wheat germplasm. It develops adapted

germplasm for diverse environments by exposing them to simulated environments, and evaluating

under different conditions (i.e. flat and raised beds, different irrigation types and frequencies, late

planting, moving back and forth between Obregon (MEX) and El Batan/Toluca (MEX) or Obregon

and Njoro, Kenya, through shuttle breeding.

Germplasm Composition: Most CIMMYT introductions were advanced lines though there are few

segregating populations. A total of 27 and 14 bread and durum wheat nurseries comprising 3243

and 5197 genotypes respectively were evaluated across locations in Ethiopia during 2010-2012.

Plot size and Testing sites: Seeds were initially checked for new pests and then planted on 2-4

rows of 20 cm apart and 2.5 m long plots at quarantine sites. Standard and local checks were

included at certain intervals. In case of stem rust, spreader rows were inoculated using mixture of

prevalent races. Then, genotypes were evaluated at Kulumsa for rusts and high yield potential; at

Melkasa for moisture deficit; at Holetta for high rainfall conditions and septoria; and at Debre Zeit

for stem rust during the main and off-season periods. All recommended management practices

were employed for each location.

Data collection: All genotypes were evaluated for their adaptation, including agronomic

performance, disease resistance, stress tolerance and end use quality parameters. Pertinent data

were recorded and genotypes promoted.

RESULTS and DISCUSSION

Since 2005, more than 60,000, 40, 000 and 10,000 germplasm from various sources were evaluated

at Njoro, Kenya; Debre Zeit and Kulumsa Ethiopia respectively. Out of these, many lines were found

to have high level (≤ 20%) of resistance to rusts specially to the Ug99 races (Table not shown). In

Ethiopia, stem rust incidence was quite high during the off-season whereas yellow rust and septoria

were more prevalent during the main season (Fig 1). About 60 and 40% of bread wheat and durum

wheat lines exhibited high levels of resistance (≤ 20% severity) to stem rust (Fig 2).

Fig. 1. Frequency (%) of bread and durum wheat germplasm under different stem rust severity classes in

CIMMYT Nurseries in Ethiopia.

CONCLUSION

Ethiopia and Kenya have a very good representative germplasm screening sites to identify rust

resistant lines in the region. As observed in Ethiopia most CIMMYT germplasm have good

agronomic performance, although rusts and septoria are the major limiting factors. Most semi-

dwarf wheat genotypes are susceptible to Septoria tritici. Identifying and pyramiding resistant

genes for rusts and septoria in those high yielding lines remains its crucial function to maintain

viable breeding program. Many national programs in East Africa have limited resources for

wheat research. CIMMYT was and will continue to be the major source of germplasm in the

region. Genetic biodiversity is a key for sustainable wheat production in vulnerable

environments. Breeders should utilize this immense diversity that is available at CIMMYT and

ICARDA. CIMMYT’s role in facilitating germplasm, information and technology exchange,

regional networking, and capacity building remain crucial in attaining sustainable wheat

production in the region. Wheat has been and will continue to contribute its share to the

economic growth in the country.

REFERENCES

Central Statistical Authority. 2010. Agricultural Sample Survey, 2010/11. Addis Ababa: CSA

Hailu Gebre-Mariam. 1991. Bread wheat breeding and genetics research in Ethiopia. pp.73-94. In: Hailu

Gebre-Mariam, D.G. Tanner, and Mengistu Hulluka (eds.). Wheat Research in Ethiopia: Historical

Perspective. Addis Ababa: IAR/CIMMYT.

Johnson, R. 1988. Durable resistance to yellow rust (stripe) rust in wheat and its implications. In: Breeding

Strategies for the Resistance of the Rusts of Wheat CIMMYT: Mexico

Solomon Asefa, Bekele Geleta; Getinet Gebeyehu and D. G. Tanner. 1995. Major achievement of bread

wheat breeding and future prospects in Ethiopia. Paper presented during the Second African Crop

Science Society Conference. Blantyre, Malawi, February 3-7, 1995.

0

10

20

30

40

50

60

70

<20 20-40 > 40

Bread wheat (N=3243)

Durum wheat (N=5197)

Frequency (%)

Stem rust severity classes

The relatively low proportion of durum wheat germplasm could be due to the exposure of the

nurseries to virulent stem rust races at Debre Zeit. Most germplasm had good agronomic

performance and thus were advanced to different stages of variety trials for further testing at

multiple locations. Well-adapted elite lines with outstanding performance were identified and

released.

Of the more than 100 wheat varieties released since the inception of wheat research in Ethiopia,

80-90% originated from CIMMYT. Bread wheat varieties, ‘Danda’a’, ‘Kakaba’,

‘Ga’ambo’, ‘Ogolcho’, and ‘Hidase’ were recent releases to replace the susceptible varieties

(Kubsa and Galama) and sustain production in the country. ‘Kakaba’ and ‘Danda’a’ are

currently under significant area cover to replace the susceptible varieties. Farmers using these

improved varieties achieved ≥ 6 t/ha yield under well-managed conditions. The major durum

wheat varieties such as ‘Yerer’ and ‘Ude’ have multiple diseases resistances, high yield and

good industrial quality. Recently, two CIMMYT originated varieties (‘Hitosa’ and ‘Denbi’)

were released, and these varieties gave 5-6 t/ha in a variety verification plots at Sinana and

Kulumsa. The country is currently improving wheat productivity by releasing elite CIMMYT

lines with adult plant resistance.

Stem rust Yellow rust Steptoria leaf blotch

Fig 1. Severity of stem rust ,yellow rust and Septoria at Debre Zeit , Meraro and Holetta respectively