In addition to a growing population, extreme weather conditions also require the continuous development of maize production. The negative impact of Western corn rootworm damage is one of the biggest obstacles to successful maize production with good yields, and it is therefore essential to record the damage caused by these destructive insects, evaluate the results and put them to practical use. For this reason, the diversification effect of the Western corn rootworm was investigated at the University of Debrecen's Látókép Crop Production Experimental Station in 2020. In our experiment, we investigated the extent of damage by Western corn rootworm larvae in maize hybrids of different maturity FAO 330 (H1), FAO 490 (H2), FAO 490 (H3), at different N-dosage (N0/120/300+PK) and soil moisture. The results showed that the extent of corn rootworm larvae damage can be detected by root tensile resistance test and TDR moisture meter. Root lodging resistance was lowest at the 0 kg ha-1 N level (78.2 kg). Based on the measured parameters of the TDR, the higher moisture content (26.3 V/V%) at the 0 kg ha-1 N level favoured the damage done by the insects in the maize stover. Increasing N supply resulted in higher yields, as confirmed by the results of analysis of variance. No significant difference was observed between the 120 kg ha-1 N and the 300 kg ha-1 N doses. Regression analysis indicated a positive, strong relationship between protein content and soil moisture (r=0.71).

Keywords: Diabrotica v. virgifera, maize, soil moisture, long-term experiment, nutrient replenishment