I - --ii

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