I - --ii

98
3. Identification of as many sources of registance to different physiologic races
as possible will assist in developing cultivars with a broad spectrum of
resistance.
Implications of Information on Genetics of Resistance on Breeding
Strategy
1. In the absence of detailed information on the nature of inheritance of resistance,
both lines showing location-specific resistance should be used. This
would provide diversity among the material being generated through hybridization
and should result in increased protection against new virulent forms
or races of the pathogen.
2. If different major genes are identified, the development of multiline cultivars
may provide a good long-term solution.
3. The identification of resistance to blight which is conferred by polygenic
systems would allow the development of cultivars with horizontal resistance
which is again likely to be a better long-term solution than relying on a single
major resistance gene.
Conventional Breeding Methods
Introduction and Selection
ICARDA has assembled 3400 kabuli germplasm accessions from 29 countries of
the world. All have been evaluated for resistance to ascochyta blight at Tel
Hadya and 22 lines have been found resistant. These lincs were tested for
adaptation and yield at Tel Hadya and other sites in Syria, and elsewhere in the
Mediterranean region. As a result, ILC. 482 (ex-Turkey) seems to be a candidate
for release for commercial cultivation in a few countries. This line has a high
yield potential, wide adaptation, high level of resistance to ascochyta blight and
acceptable seed characteristics. This is perhaps one of the rare examples of a line
having resistance to a disease with a high yield potential, and wide adaptation
being identified directly from a gerniplasm collection. Future collections of
germplasm may yield additional sources of resistance.
Another line, ILC. 484 also has good agronomic and resistance attributes like
ILC 482 and may also be considered for release in a few countries. Three tall
lines, namely, ILC. 72, 202 and 3279 have been found resistant to ascochyta
blight and high yielding but have unacceptable seed characteristics for the
Mediterranean region. But in certain countries where mechanical harvesting is
the primary requirement and such seed quality is acceptable, these lines may also
become candidates for release.