Surveys led by Dr Fikre Handero (SNNPR Agricultural Research Institute) with assistance from Dr Getaneh Woldeab (Ambo PPRC) and CIMMYT were undertaken in the mid-altitude / highland areas of SNNPR between Butajeira and Arba Minch during the period 5-10th Nov 2012. A total of 44 fields were surveyed, these were predominantly bread wheat with a few triticale fields included in the Chencha highlands close to Arba Minch. Surveyed crops were mostly at the milk-dough growth stage. Following the 2010 yellow rust epidemic there has been a rapid uptake of the resistant cultivar Digelu. On the survey, 15 out of 38 farmer fields surveyed (40%) were planted with Digelu and the actual proportion of Digelu in the area surveyed was considered to be higher, as there was some avoidance of Digelu on the survey due to the high rust resistance observed.
stem rust was widespread on the survey, but at low incidence and severity (<20% and predominantly trace amounts). Stem rust was present in 21 of the 44 fields surveyed, but moderate (20-40%) severity was only observed at 1 site. Most of the stem rust sites were below 2400m (mean elevation of positive sites 2283m, overall range 1993-2792m). Kubsa and Galema were the cultivars on which stem rust was most often recorded. Digelu had good resistance with very few, tiny pustules observed. The improved cultivars – Dand’a, Hidase, Kakaba and Shorima all had a very low incidence and severity of MSS to S type pustules at the Angacha Research Station. A total of 24 DNA samples and corresponding live samples were collected on the survey. These are undergoing analysis at the USDA-ARS, Cereals Disease Lab, Minnesota and the Ambo PPRC, Ethiopia.
Yellow rust was observed at 18 of the 44 sites surveyed. The disease was widespread but generally at low levels of incidence and severity. High incidence of yellow rust was observed at 8 sites in the southern part of the survey area, predominantly on the cultivar Galema. Only 2 sites in the Chencha highlands had high severity (>40%) of yellow rust on the cultivar Galema. The mean elevation of sites with yellow rust was 2364m (range 1993-2795m). Yellow rust was also observed on Triticale in the Chencha highlands. Fourteen samples of yellow rust were sent to the Global Rust Reference Center in Denmark for race analysis.
Leaf rust was recorded at 21 of the 44 sites surveyed. High incidence was observed at 7 sites, but generally there was low to moderate incidence and severity of leaf rust within the survey area.
Septoria was the most prevalent and widespread disease recorded on the survey, all cultivars (including Digelu) were affected. This matches observations from other regions of Ethiopia with conditions in 2012 main season being particularly favourable for Septoria development.