By: Teklay Abebe*, Getaneh Woldeab, and Woubit Dawit *Corresponding author: teklayabebe6@gmail.com or teklayabebe@yahoo.com

1. Seasonal variation in occurrence of wheat rusts with special consideration of stripe rust in Tigray,
Ethiopia
Teklay Abebe , Getaneh Woldeab2, and Woubit Dawit3
1
1
TARI, Alamata Agricultural Research Centre, PO. Box 56, Alamata, Ethiopia
2
EIAR, Ambo Plant Protection Research Centre, PO. Box 37, Ambo, Ethiopia
3
Ambo University, PO. Box 19, Ambo, Ethiopia
*Corresponding author: teklayabebe6@gmail.com or teklayabebe@yahoo.com
Introduction
Wheat rusts are major diseases of wheat in the Tigray region of Ethiopia, causing significant
losses to yield and quality in years with suitable conditions. The rust prevalence changes from
year to year and from place to place, depending on climatic conditions.
Materials and Methods
A survey of wheat rusts was carried out in southern Tigray during 2010 and 2011 to monitor
rust diseases status and relative economic influence. Roadside and farmer wheat fields were
visited and data were collected from each 5-10km stop.
Results and Discussion
Sixty-six and 52 wheat fields were examined for the presence of wheat rusts in 2010 and 2011,
respectively. Of these, 6.1% were infected with yellow (stripe) rust, 34.5% with leaf rust, and
33.3% with stem rust in 2010, and 63.5%, 11.5% and 7.7%, respectively in 2011. In 2010, the
lowest mean (0.5%) incidence was recorded for yellow rust, while the highest score (24%) was
noted by leaf rust, followed by stem rust (15.1%). The highest severity was recorded for leaf
rust with range and mean severity values of 0–100% and 11.9%, respectively. This was followed
by stem rust, with a range of 0–50% and a mean severity of 12.3%. In contrast, the lowest range
and mean severity was registered by yellow rust with a mean severity of less than 1%. However,
a complete shift occurred during the second year (2011), when yellow rust became the most
important disease in all surveyed areas, putting a significant wheat proportion/germplasm at
risk. The peak incidence and severity of stripe rust reached 100% in some places. The overall
mean incidence and severity of stripe rust was 25.9% and 19.5%, respectively while the mean
incidences and severities of leaf and stem rusts were much lower, below 5%.
34.9 63.5
33.3 70
40 23.95
60
30 11.9
15.1 50
20 40 25.9
8.4 19.5
10 6.1 Leaf rust 30 11.5
0.5 Stem rust 20
7.7 4.2
0 0.2 10 2.5 Stripe rust
Stripe rust 0.2 Brown rust
0 0.33
Stem rust
Fig. 1. The status of wheat rusts in south Tigray in 2010 and 2011, respectively
The occurrence and variability of stripe rust in most bread wheat cultivars is of concern, as it is
expected to have a major economic significance in the Tigray highlands, especially with climate
change.