Plant breeding for organic and sustainable, low-input agriculture

Yield performance of yellow rust resistant winter durum wheat landraces under dryland
conditions of Turkey
T. Akar , F. Dusunceli, M. Avci, S.Yazar, T. Sanal
Central Research Institute for Field Crops, Ulus, Ankara, Turkey.
Turkish highlands are characterized with severe cold damage before and after long winter season
and drought period especially just after pollination stage of cereals which limits yield level
around 2 tons per hectare. Farmers especially living under remote areas of these regions
generally use low fertilizers and chemicals due to their limited socio-economic situations and
unfavorable ecological conditions. In addition to these, erratic rainfalls some years could cause
yellow rust epidemics which resulted in low yield and grain quality for wheat production. So far
many effort were spent for improving yellow rust resistant bread wheat cultivars but there are
few durum wheat cultivars resistant to yellow rust which have been cultivated under dry-lands
of Turkish highland.
So for that reason twenty durum wheat (Triticum durum L) landraces collected from various
provinces of Turkish highlands including old and new durum wheat cultivars such as Kunduru,
Kiziltan, C-1252, Cakmak and Altintas developed for Central Anatolia and Transitional Zones
(CAT) of the country were tested under mist-irrigated conditions in order to determine their adult
plant yellow rust (Puccinia striiformis f. sp. tritici) reactions. These germ-plasm screened for
yellow rust population consisting of Yr2, Yr6, Yr7 and Yr9 virulence genes during 2003 and
2004 seasons were winter planted.
Average of yellow rust infection coefficient of populations and cultivars was 32,44 in 2003 while
26,24 in 2004. It is clearly indicated that more severe epidemic occurred at Adult Plant Stage
(APS) in 2003, therefore variation between resistant and moderately resistant line numbers
greatly changed. Selected lines and cultivars number were 31 in 2003 while 70 in 2004,
respectively. 20 of the 30 resistant and moderately resistant lines selected from 18 populations
according to the first year epidemic results were also included one year yield trial including five
checks under low input areas of Turkish highlands in the next year. Yield, quality and yellow
rust resistance data were bi-plotted. Promising yield and grain quality data of some yellow rust
resistant lines compared to the commonly cultivated checks demonstrated that lines 19-5, 13-5,
20-5, 15-1, 17-4 and 13-4 can be directly used as candidate lines or genetic sources for durum
wheat breeding studies under dry-land conditions of Turkey. Due to the fact that these types of
disease resistant germ-plasm do not need chemical control and that they can tolerate low input
application they are suitable for small scale farmers in the region.
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