Dates of chemical treatment against cutworm were determined according to Zach (1966) and on the base of obtained results from field and growth chamber experiments. Experiments were aimed at the affect of heat sum and sum of effective temperatures on adds incubation and larvae development till L2.
The aim of the experiment conducted in 2006–2008 in Żelazna was to determine the degree of root damage caused by cutworms and their effect on root yield and its quality of two cultivars of sugar beet. The evaluation was performed including two different rotations (after sugar beet and after spring wheat) and different postharvest methods of tillage. Cultivation of sugar beet after sugar beet during 3 subsequent caused fourfold increase in the number and percentage of damaged roots by cutworms. Subsoiling significantly lowered the number of damaged roots by cutworms. Different variants of postharvest tillage did not influence the percentage of damaged roots per plot. Traditional postharvest tillage caused a significant increase of damage degree by cutworms. Percentage share of damaged roots negatively affected biological and technological yield of sucrose, and the degree of root damage negatively influenced root yield of sugar beet.