Irrigation Effects of Red Beet as Affected by Rainfall in Different Regions of Poland

The purpose of research was to determine the irrigation effects on the root yield of red beet grown on light soil in different regions of Poland, depending on rainfall amounts during the period July-August. Relationship between the increases of root yield and applying of irrigation was estimated using the Grabarczyk’s formula. The amounts of rainfall in the average dry year, medium dry and very dry were determined by the Ostromecki’s method. Rainfall deficits in the cultivation of red beet were determined according to the difference between optimum and real precipitation in five meteorological stations. The highest precipitation deficiencies in the red beet crops in July-August were observed in the central Poland, where amounts 51–52, 98 and 118–124 mm, in average dry, medium dry and very dry years, respectively. The highest increases of the root yield obtained using irrigation were estimated also in the central Poland, where amounts 9.26 and 8.96 t ha−1, 17.30 and 17.28 t ha−1, and 20.92 and 22.00 t ha−1 in average dry, medium dry and very dry years, respectively. The increases of red beet yield obtained using irrigation showed the large possibilities of raising its productivity in the field cultivation under optimal water conditions.