Specifics of irrigation regime for growing early potatoes in southern Slovakia | Zvláštnosti závlahového režimu pre pestovaní skorých zemiakov na juhu Slovenska

Irrigation is an inevitable requirement for agricultural production. Exploitation of irrigation in various climatic areas expects to bring increase in yield of agricultural crops. Water conditions slowly alter spatial configuration of fields, along with heterogeneity of soil in the given area (structure, topography, field water capacity, filtrate proportion, and others). Therefore, irrigation requirements can be different in variant sectors within the specific location. In this paper the soil moisture regime for growing early potatoes (the variety Impala) in two horizons (depth 0.3 m and 0.6 m) was evaluated. In the first horizon (0.3 m) the value of actual moisture of soil decreased four fold below the hydrolimit value of wilting point. However, in the deeper horizon (0.6 m), the value of the actual moisture of soil fell below the hydrolimit value of the wilting point only once. In the horizon of 0.3 m, the hydrolimit value of the field capacity of water [FC] was 50.6%, while in the deeper horizon (0.6 m) it was 56.5%. The value of the hydrolimit of the wilting point in the depth of 0.3 m was 22.59%, and in the depth 0.6 m it was 23.83 %. The actual moisture of the soil ranged approximately 70% between the values of low water capacity (Zmin) and the wilting point. Our results show that used irrigation was late and less effective, because the actual soil moisture content could not reach the value of the low water capacity after 15.6.2004. In this case, the first irrigation amount of water should have been applied in the middle of June, when the soil moisture started its significant decrease. Afterwards, it would have been easier to manage the trend of the present soil moisture content and place it above the low water capacity Zmin. Evaluated results show that the failure of the first planned irrigation rate had significant negative affects, since it was impossible to correct the optimal water requirements for plant species.