Citrus Yield and Quality as Affected by Subsurface Irrigation1

Supplemental subsurface irrigation resulted in increased yield and fruit size of ‘Washington’ navel and ‘Owari’ satsuma oranges. The larger fruit size, as a result of irrigation, induced a slight but significant increase in peel thickness. Supplemental moisture resulted in a reduction in juice content of ‘Owari’ satsuma. With ‘Washington’ navels irrigation increased juice content, or was equal to the control, in 4 out of 6 years. Irrigation did not greatly influence pH, percent soluble solids or solids/acid ratio of the juice. Two years results showed that irrigation did not affect peel color of ‘Washington’ navels. In 1973 irrigation had no effect on juice color of both types of oranges.