Yield and quality of potato tubers under different regimes of conventional sprinkler irrigation

The conventional sprinkler irrigation system is widely used in water supplementation in the potato crop. This is pressed due to the low efficiency of water application, so it has been replaced by central pivot and trickle irrigation, which is more efficient. The adoption of more efficient systems for irrigation management programs can increase the efficiency of water use on potato crop. In view of this, the study aimed to evaluate the effect of different water blades and irrigation regimes on potato cultivation during the fall/winter of 2007, in the southern region of Minas Gerais state, Brazil. The experiment was conducted in a randomized block experimental design with split plots and four replications. In the plots two irrigation frequencies [F4 (four days) and F6 (six days)], and in the subplots the four water irrigation levels were evaluated, based on the percentage of total irrigation necessary (ITN) (L-1: 80% ITN, L-2: 100% ITN, L-3: 110% ITN and L-4: 125 ITN). Qualitative variables were analyzed by t test with a probability level (<= 10%) and regression analysis, considering the values of the regression coefficients (R-2). The total cycle was 119 days with average evapotranspiration from 181.0 to 186.4 mm. The lower water blades 129,5 mm and 133,3 mm were applied in the treatment L-1, in the frequency 4 and 6 days and the higher water blades 203.4 mm and 209.3 mm in the treatment L-4, in the frequency 4 and 6 days respectively. The highest yield of great tubers production occurred in water blades of 0.99 and 1.05 ITN and in the frequency F4 and F6. The highest production was obtained in F6, with the water blade of 1.06 ITN. The highest value of efficient water use was 38.05 kg of tuber m(-3) of water, obtained with the combination of treatments F6/L-2 and the lowest value 32.89 kg of tuber m-3 of water in the combination F4/L-1.