Physiological Responses of Wheat to Early Sowing Under Nonirrigated Cultivation and to Late Sowing Under Irrigation*

Advancement of sowing date for taking advantage of more favourable soil moisture status in barani cultivation, and delay in sowing in a multiple cropping system with irrigation, should expose a wheat crop to high temperatures. A brief account is given, in this context, of the effects of high temperatures on the early and late growth stages of the wheat plant. The importance of a comprehensive study of the effects of early sowing on early developmental stages, and of the effects of late sowing on grain growth, in a wide range of genetic stocks is discussed in relation to the programme for breeding of cultivars suitable for early and late sowing.