Meeting the Challenge of Yellow Rust in Cereal Crops - ICARDA

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considerably increased. The peak wheat production of 645 000 tonne was
achieved in 2003.
Among the diseases affecting yield during the last 15 to 20 years, smuts
were considered as dangerous. However rusts, particularly yellow rust, is
becoming a very dangerous disease that significantly decreases grain yield.
Infection by yellow rust has been observed in all zones of Tajikistan under both
irrigated and rainfed conditions. The increase in yellow rust infection has a
direct relationship with expansion of the growing area in all Central Asian
countries and a decrease in existing natural barriers. Severe epidemics of
yellow rust have occurred in years with high rainfall, and the pathogen
damages wheat everywhere. Yellow rust epidemics may totally destroy wheat
crops and decrease wheat yield by up to 60–70%. Most of the widely grown
wheat varieties are very susceptible to this disease.
Materials and methods
After independence several wheat varieties were introduced and disseminated
to farmers by international humanitarian agencies. However, the
GTZ/CIMMYT Project aimed to strengthen wheat breeding and the seed
multiplication system in Tajikistan. During the implementation of the project
since 1999 to present, a number of wheat varieties and advanced lines have
been tested in different agro-ecological zones of Tajikistan, varying from 500
up to 1800 masl. The genotypes tested originated from CIMMYT, ICARDA and
the breeding programmes of USA, Turkey, Russia, Ukraine, Bulgaria,
Hungary, Iran, Kazakhstan and Tajikistan. In addition to yield data, disease
resistance, and specifically yellow rust reaction, was used as a criterion to
select the best varieties for release and large-scale multiplication. In 2002, 30
entries were tested in multilocational testing nurseries (MLN); 28 in yield
trials; and 36 in preliminary yield trials.
Results and discussion
The results of uniform trials show that there are several varieties very well
adapted to the climatic conditions of the country, that demonstrate resistance
to rust, and produce high grain yield. Among genotypes selected, cultivars
such as Jagger, Atay, Sulton 95 and Kinaci became very popular in Tajikistan
due to high yield and yellow rust tolerance.
The advanced lines and varieties tested in multilocation nurseries, such as
Kauz, Attila, Zander-12, PYN/BAU, CHAM 6/1D13.1/MLT,
GRK//ESDA/LIRA, NWT/3/TAST/SPRW//TAW12399.75, DORADE-5,
NORKAN//TJB406.892/MON, TAST/PCH//BEZ2B/CGN/3/ZAR
VORONA/HD2402 and RSK/CA8055//CHAM-6, showed rust resistance.