I - --ii

107
Variation in disease reaction has been observed from location to location.
Although a few lines have been identified as resistant across all sites so far tested,
many more lines have reacted differentially. One reason for this may be the
existence of different pathotypes and further information on variation in virulence
of the pathogen is urgently required. It is necessary that all resistant lines
developed at ICARDA should be widely tested in as many environments as
possible. It is also imaportant to reevaluate the germplasm collection in other
environments as other sources of resistance may exist which may not have been
identified by the screening conducted at Tel Hadya.
In order to ensure that this widespread testing is carried out effectively it is
essential thait ICARDA and the national programs work together in close collaboration.
In several countries, adequate facilities and manpower already exist
for carrying out the work. In others, ICARDA may be able to make a special
input in terms of training, frequent visits, etc. In order to work more closely with
the national programs, ICARDA is currently developing several subregional
programs (e.g. for North Africa) through which it is hoped to achieve a greater
degree of coordination of the research efforts. The joint efforts of all concerned
scientists in the region are required if the advantages of ascochyta-resistant
cultivars are 'o be realized on farmers' fields in the region.
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