3.2. Yield and yield components
The results of the variance analyses (ANOVA) for tuber yield and its components were
presented in Table 5. The mean values of the yield and yield components were given in
Tables 6 and 7.
The surface or subsurface drip irrigation methods had no significant effect on yield and
the yield parameters in both years. Phene (1995), Weatherhead and Knox (1998) also
reported no significant differences between surface and buried tape methods on potato
yields. However, the irrigation levels significantly affected all yield parameters in both
years (Table 5). The irrigation methods levels interactions were also significant on tuber
yield per plant and total tuber yield per hectare in 2000 (Table 5).