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Considering the limited water resources in Iran and the need to improve agricultural water productivity, the nessesaty to study the volume of irrigation water in the production of limes in Iran becomes apparent. Therefore, in this field study, irrigation water volume and limes yield in over 210 selected orchards in Fars, Hormozgan, Kohgiluyeh, Boyer-Ahmad and South Kerman provinces were measured directly. Analysis of variance was used to investigate the possible differences in yield, irrigation water volume and water productivity in limes production. The results showed that the differences in yield, applied water volume, and indicators related to water productivity were significant in the mentioned provinces. The weighted average, minimum and maximum yield of limes were 21.6, 14.3 and 30.1 tons per hectare, respectively. The weighted average, minimum and maximum volume of applied irrigation water were 12578, 8390 and 13963 cubic meters per hectare, respectively. The weighted average, minimum and maximum irrigation water productivity were estimated to be 1.90, 1.46 and 2.80 kg/m3. Weighted average, minimum and maximum water+long-term effective rainfall productivity was 1.59, 1.25 and 2.40 kg/m3. Weighted average, minimum and maximum of water and current year effective rainfall productivity were 1.75, 1.35 and 2.71 kg/m3, respectively. The proportion of irrigation water volume of limes orchards with gross water requirement in selected provinces was similar. In general, the average difference between the depth of irrigation water of limes and annual and long-term gross water requirement in the country was -17 and -1 percent, respectively. In the case of lime orchards, the results were different from the limes orchards. In Fars province, the depth of irrigation water was higher than all three scenarios of gross water requirement and in Hormozgan province was less than all three scenarios. On average in all orchards, the irrigation water depth of limes orchards was 17% higher than the long-term gross water requirement and 1% lower than the annual gross water requirement. In the limes under drip irrigation system compared to surface irrigation, fruit yield and water productivity increased significantly and irrigation water volume decreased. On average, water application efficiency in the lime orchards was estimated to be about 90%.
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