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Proceedings of the Workshop on Ascochyta Blight and Winter Sowing ofChickpeas (Saxena, M.C.
and Singh. K.B., eds.), ICARDA. 4-7 May 1981, Aleppo, Syria
Physiological and Moisture-Use Studies on
Growth and Development of
Winter-Sown Chickpeas
J.D.H KEATINGE and P.J.M COOPER
Crop Physiologist and Soil Physicist, respectively, iCARDA, Aleppo, Syria
The adoption of a winter sowing agronornic practice has only become realistic
under Syrian environmental conditions following the development of chickpea
lines resistant to ascochyta blight. Winter sowing is likely to result it, the vegetative
and early reproductive phase of development taking place under cool, moisture
assured conditions, thus deferring the onset of the period of high evaporative
demand and consequent moisture stress to c-op's later growth cycle. Potential
productivity of winter-sown chickpeas should 'hus be enhanced in comparison
with the traditional spring-sown ones.
However, the interactions between physical environmental factors, :uch as
radiant energy interception, moisture supply and temperature, and growth and
development are usually complex. This particular experiment is designed to
investigate these interactions, to examine the intensity and timing of onset of the
significant environmental constraints on potential chickpea productivity. In addition,
the ascochyta blight resistant lines can currently be subdivided in terms of
their br nlching morphology being either of an erect or spreading habit. Such
morphological differences may well result in genotype-environment interaction
and in broad terms these are considered in this experiment.
Methodology
One line representing each morphological group was selected, for the erect group
- ILC 72 and for the sprea'ling group - ILC 482. These lines were handplanted
in early November 1980 at a rate sufficient to achieve what is currently considered
to be optimum stand r'ensity, i.e. 300,000 plants/hectare. An additional
treatment was employed in the erect line in which a superoptimal density of
600,000 plants/ha was established to examine the effect of more rapid canopy
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