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Proceedingsofthe Workshop on Ascochyta Blightand Winter Sowingof Chickpeas (Saxena. M.C.
and Singh, K.B.. eds.). ICARDA. 4-7 May 1981. Aleppo, Syria
Third Session: Winter So%.ag
Agronomic Studies on Winter Chickpeas
M.C. SAXENA
Agr.,nomist/Crop Physiologist,
Food Legume Improvement Program. ICARDA, Aleppo, Syria
The productivity of an agro-type can be maximized by developing the agronomic
practices and crop genotypes that would ensure matching of various phases of
crop growth and development with the periods of crop season when most of the
physical factors of environment are at their optimum for these phases: The winter
planting of chickpeas, in the 'lowland' zone of West Asia and North Africa,
which is characterized by coastal to continental Mediterranean climate, is one
such exercise inoptimizing the matching of growth phases with the environment.
The climatic endowments of the 'lowland' zone of the West Asia and North
Africa region have been discussed in detail by Harris (1979), Kassam (1981) and
Smith and Harris (198 1). From these studies, it isclear that in most of this zone,
a favorable soil moisttre balance (because of increasing rainfall and low evaporative
demand, coupled with mild temperatures) permits the winter period to be
quite suitable for extending the potential growing season of a crop like chickpea,
which is traditionally planted in spring.
The general trends ;n the physical environment in relation to various stages of
ontogenic development of achickpea crop, when planted on different dates, are
shown in Fig. 1. It isapparent that the period of vegetative and reproductive
growth of the winter-planted crop is exposed to relatively lower thermal and
better moisture regimes than that of the spring-planted crop. Thus, the winter
planting obviously results in the development of plants with a larger vegetative
frame capable of supporting a bigger reproductive structure, thus leading to
increased productivity. Data have beer, generated, in the past, to support this.
They will be briefly discussed in !ater sections.
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