ITEMS FROM SYRIA
P. O. Box 5466, Aleppo, Syria
H. Ketata 1, H. Braun 2, A. Morgounov 2, O. Mamluk 1, S.K. Yau 1, K.
Makkouk 1, M. El Bouhssini 1, F.J. El Haramein 1, M. Tahir 1, H. Ekiz 3,
M. Keser 3, L. Cetin 3, S. Beniwal 1, and A. Amiri 4.
1 ICARDA; 2 CIMMYT; 3 Cereal Improvement Program, Turkey; and 4 Cereal Improvement
Program, Iran.
Growing conditions.
Despite a high seasonal rainfall (434 mm), the growing conditions at Tel
Hadya, Aleppo, Syria, were marked by drought throughout the grain-filling
period (no rain after heading) coupled with high temperatures during the
same period (mid and upper 30's and up to 41°C) and resulted in low
yields and very shriveled grains. Earlier in the season, a 10-week cold
spell (45 frost days, with an average minimum temperature of 5.6°C
during January-March) severely damaged the spring types and enabled a good
screening of facultative types for frost tolerance. The temperature pattern
was similar at Breda, but lower rainfall (231 mm) at this site explains
the 50 % yield reduction as compared to Tel Hadya (2 T/ha vs 3.8 T/ha).
Sarghaya, a highland site at 1450 m and 70 km northwest of Damascus, was
used to screen facultative and winter wheat germplasm for adaptation to
highland environments similar to those in mountainous areas in Lebanon and
North Africa. There were 148 frost days at Sarghaya, with a minimum of 19°C
recorded in early February, and an average minimum temperature of - 7°C
from October through April. Natural epidemics of yellow rust, leaf rust,
and stem rust were enhanced with one irrigation in May.
Germplasm development and screening.
Improvement of facultative and winter wheat at ICARDA is conducted jointly
with CIMMYT and the Turkish national wheat research program within the framework
of the International Winter Wheat Improvement Program; IWWIP (see Items
from Turkey in this newsletter); and in collaboration with several NARS's
from West and Central Asia and North Africa (the WANA region) including
Iran, Pakistan, Afghanistan, Azerbaijan, Armenia, Georgia, Turkmenistan,
Uzbekistan, Kyrghyzstan, Tajikistan, Kazakstan, Morocco, Algeria, and Syria.
Research at ICARDA, Syria, is focussed on: (a) enhancing the genetic variability of IWWIP materials through crossing with land races and specific germplasm from the region's highlands and cold areas and (b) germplasm screening for diseases (mainly yellow rust and common bunt), insects (Russian wheat aphid, wheat stem sawfly, and Hessian fly); BYDV; boron toxicity; and bread-making quality. Desired types are identified through 2-year repetitive testing before inclusion in the genetic stocks for specific traits that are made available to requestors through IWWIP.
Yellow rust epiphytotics were used successfully at Tel Hadya over the last 3 years, leading to a steady improvement of resistance to the disease in germplasm. Combined with the simultaneous testing of the same materials in Turkey and Iran, this yellow rust screening contributes to higher and more stable wheat yields in the cool and cold areas of the WANA region. Based on this season's screening of segregating populations (750 F2s) and preliminary yield trials (1,500 entries), the following parents seem to be good combiners, especially for yellow rust resistance:
The following advanced entries combined resistance to yellow rust and tolerance to BYDV and to boron toxicity:
Observational plots of intermediate, advanced, and elite yield trials were
grown at Sarghaya, where they were screened for winterkill, spring frost,
and diseases. About 1,700 entries were evaluated for protein, kernel hardness,
and 1,000-kernel weight.
Germplasm characterization and targeting:
Special studies on vernalization and photoperiod characterized wheat
germplasm, helped to understand adaptation to the highlands and cold areas
of the WANA region, and targeted germplasm for specific megaenvironments.
The 48 cultivars and advanced breeding lines were grouped into three categories:
(a) entries with a high vernalization requirement and a low response to
daylength, representing true winter types, including Karl, Dogu 88, Sadovo
1, and MV17; (b) entries with a moderate vernalization requirement and a
moderate response to daylength; these entries are semi-winter or facultative
types, and included cultivars such as Vratsa, BJN C.31, Fandango, BJN C
79, and 'SXL /Glennson'; and (c) spring or spring-like types that head in
summer planting at Tel Hadya and showed a low response to vernalization
and a moderate response to daylength.
In most of the WANA region, spring frost is a frequent phenomenon and usually more damaging than winter cold, which is only severe in limited areas of eastern Turkey and northwestern Iran. Successful cultivars that stood this type of stress for years are old local varieties (land races) such as Sardari in Iran and Achoura and Kirik in eastern Turkey. These and other land races in the region possess a high level of winter hardiness, vernalization, and photoperiod to enable them withstand and/or escape frost, as well as the ability to rapidly fill the grain. This allows them to avoid terminal drought and heat stresses, typical of these environments. Some of the entries of the second group were found to possess such land race characteristics and are being used in the crossing program. Recent results of 3-year testing in northwestern Iran showed that the three most promising breeding lines are derived from crosses involving local cultivars.