I - --ii

proposed a biochemical explanation involving the sulphydryl (-SH) groups of the
proteins in the cell.
The study has helped in identification of a few lines that are resistant to this
kind of stress, which is of importance in winter planting of chickpeas in the
region. Fortunately several lines identified as frost resistant are also resistant to
ascochyta blight. Some of these are ILC 3279, 72, 194, 202, 482 and 484. ILC
202 showed a high level of tolerance even at the flowering stage. It will be
desirable to confirm the tolerance of these lines to late frost either under controlled
environmental conditions or by growing at locations where frequency of
late frost is higher.
Summary
For the success of winter planting, tolerance to cold winters during the early
vegetative phase as well as tolerance to sudden late frosts are essential attributes
of a chickpea genotype. With this objective in view, accessions of kabuli genotypes
were evaluated against these two stresses under field conditions.
The evaluation at Tel Hadya (Syria) and Terbol (Lebanon) sites of ICARDA
in the lowland region during 1978-79 revealed that most chickpea lines can
tolerate the cold winter conditions of this region. However, evaluation at the
intermediate elevation site at Hymana in the Anatolian Plateau (Turkey) showed
that only a few lines were capable of tolerating the harsh winter conditions there.
Six lines have been identified as tolerant, and they are being utilized in the
hybridization program for the development of high-yielding, winter-hardy cultivars,
for the plateau regions of Turkey and Iran.
The evaluation of the kabuli collection for late-season frost tolerance showed
that there was no correlation between the tolerance rating at the preflowering
and seedling stages. Evaluation at the reproductive phase seems to be more
desirable. A large number of lines have been identified as frost resistant, but they
will have to be reevaluated for confirmation.
The need for evaluation of more lines and an understanding of the bases for
cold tolerance and late frost resistance has been emphasized.
References
HARRIS, H.C. 1979. Some aspects of the agroclimatology of West Asia and North Africa. In Food
Legume Improvement and Development (Hawtin, G.C. and Chancellor, G.J. eds), ICARDA,
Aleppo, Syria and IDRC, Ottawa, Canada.
HAWTIN, G.C. and SINGH, K.B. 1981. Prospects and potential of winter sowing of chickpea.. in
the Mediterranean region. This volume, pp. 7 -16.
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