Variability of yield of an irrigated crop and its causes: 2. Input data and illustration of results

The data needed in order to evaluate the impact of the variability of different parameters upon crop yield variability were collected from various sources in the literature. Two fields (Paoche in the United States and Bet Dagan in Israel), which had been studied extensively in the past, were selected as representative for a wide range of soil conditions. In a similar manner, standard values of the expectations and extreme values of variances of other soil‐plant‐atmospheric parameters were inferred from the literature. The adopted values are summarized in a table. The dependence of the relative yield and its derivatives upon each of 19 parameters, while the remaining ones are kept fixed at their standard expected value, is illustrated.