Ratio of yield to irrigation use was highest in Exp-1 with

drip irrigation and lowest with sprinkler irrigation (Fig. 8).

Higher rainfall in Exp-2 caused the ratio to drop rapidly as

irrigation use increased. Actual irrigation efficiency for Exp-2

was 0.48 tons/acre-inch. The ratio of yield to irrigation use was

nearly constant in Exp-3 because irrigation was the only source of

water for plant growth. About 2.5 tons of tomatoes/acre-inch of

irrigation were produced in Exp-3; this is similar to values in

Exp-1 after accounting for rainfall effects. Therefore, 15 inches

of effective drip irrigation would produce about 38 tons of

tomatoes.

 Yield:Irrigation Use Ratio (Tons/Ac-in)
 4
 Irrigation Exper.
 I Exp. #1 E Exp. #2 E Exp. #3




 2-


 1- M



 38.76 10.32 26.9 19.43 12.96 6.48 8.98 7.83 4.02
 Total Irrigation (Inches)

Figure 8. Ratio of yield:irrigation use versus total irrigation
for all experiments.