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84<br />
ing of the remaining collections of desi germplasm maintained at ICRISAT<br />
Center and future collections of 'the kabuli germplasm will be continued. The<br />
availability of a large number of resistant lines in desi and kabuli background<br />
should help breeders to develop-resistant and high-yielding cultivars.<br />
It was earlier believed that kabulis lack resistant genes to ascochyta blight but<br />
screening a large collection revealed many lines having a high level of resistance.<br />
However, it is worth noting that none of the extra large seeded kabulis had the<br />
desired level of resistances. Most of the resistant lines had small seed size. But is<br />
evident that desis (10.91%) have a higher proportion of resistance thon the<br />
kabulis (0.65%).<br />
Most o1 the resistance sources have their origin in the USSR, Iran, India,<br />
Afghanistan and Turkey., which are belived to be the primary and secondary<br />
centers of the origin of chickpea. The majority of the desi resistant lines was<br />
folad to be black st:eded originating from Iran. Kaiser (1973) also found most of<br />
the resistant lines to be black seeded in Iran. Additional search for sources of<br />
resistance in black-seeded types originating from Iran should result in greater<br />
success. More collections from the region on a priority basis is suggested before<br />
the landraces are replaced by new genotypes.<br />
In the past, lines identified as resistant at one location were usually not tested<br />
out at other locations (Grewal and Vir 1974; Nene et al. 1979). A strong need is<br />
feit to collect all sources of resistance and test them at other locations to identify<br />
lines with a broad spectrum resistance. Also, a line may have become susceptible<br />
in its original habitat due to the emergence of a new race but it may still be<br />
r-,;tant to the original race that may be prevalent elsewhere. For example, C<br />
235, identified as resistant in India during 1962 is now found susceptible there<br />
(Bedi and Athwal 1962) b'it has shown resistance in Syria and some other places.<br />
The international testing of resistant lines through CIABN helped in the<br />
identification of six lines, namely, ILC 72, 191, 194, 202, 3279 and PCh 15,<br />
resistant across locations and/or years. These lines seem to possess location/race<br />
nonspecific or broad spectrum resistance and should be very useful in the future<br />
breeding programs. Such lines were not available earlier. In addition, a large<br />
number of lines, such as ILC 182, 183, 200, 201, 2380 and ICC 1903 were found<br />
promising across locations and years.<br />
The differential reaction of some lines at different locations strongly indicates<br />
the presence of races. Aujla (1964) and Bedi and Aujla (1969) have indicated the<br />
possible existence of races in A. rabiei in India. Later Vir and Grewal (1974)<br />
identified two races and a biotype. The present study indicates the variability in<br />
the blight pathogen in the wider geographic region.<br />
Maximum effort has gone into tackling the blight problem in Pakistan since<br />
the early 1930s, yet the solution is nowhere near. It could be due to lack of either<br />
durable sources of resistance or sustained effort on the part of plant breeders. It<br />
is not only true for Pakistan but also for other parts of the world. In the Mediter