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In dryland areas of India, rainfall is the main source of water for raising crops. For these areas, the greatest problem is not water shortage per se, but rather the tremendous variability in rainfall from year to year and season to season. In planning for the coming season, we currently have little or no ability to predict the date of the onset of rains or their amount, distribution, or duration. However, uncertainty about rainfall is lessened when information is available concerning the possible variability and frequencies of historical occurrences of rainfall. This information can be obtained by coupling water use to water production functions that enable estimates of associated crop yields and economic returns (Stewart and Hagan, 1973; and Doorenbos and Kassam, 1979). Therefore, in the present study, a simple water balance model developed by Frere and Popov (1979) was used to estimate crop water use; when coupled with water production functions, it explains yield behavior of the following crops (with respect to different dates of commencement of the rainy season): sorghum (Sorghum bicolor L. Moench), pearl millet (Pinnisatum americanum L. Leek), sunflower (Helianthus annus L.), castor (Ricinus communis L.), and pigeon pea (Cajanus cajan L. Millisp.) These crops are grown in Hyderabad under high management and rainfed conditions.