**1. Introduction**

European corn borer (ECB) is a polyphagous insect able to attack more than 200 different plant species. This pest mostly damages maize plants; however, a yield of peppers can be decreased up to 60% due to the ECB feeding activity [1]. The intensity of the ECB attack in Croatia often reaches 100% of maize plants in the last 20 years, with few exceptions, which could be related to recent global changes in climate [2]. The cultural and biological controls are mostly used for the management of ECB in maize, while chemicals are mostly applied in sweet maize and production of maize for seeds. Tolerant maize hybrids are a very important

tool in integrated pest management programs against ECB. Plant breeders successfully developed hybrids with stronger stalk, a larger root system, and such plants are more tolerant to this pest. Tolerant hybrids are also characterized by the low potential of plant lodging and yield losses in conditions of the highest ECB infestation and stalk damage [3, 4]. One ECB larvae per plant on commercial hybrids can reduce yield up to 6.05% [5]. The amount of plant-available water has been studied as a potentially important factor for ECB infestation and damage. Irrigated plants have a higher yield, and grain quality is better [6]. If the water supply is satisfactory, plants will adsorb more micro and macro elements. Nitrogen is the most important essential element, and plants adsorb it in a mineral form. Agricultural soils usually contain 0.1–0.3% of nitrogen, and from this, only 1–3% is available for plants. Maize plants under nitrogen fertilization treatment are attractive for ECB females for laying eggs. Such plants contain more quality ingredients for larval nutrition. The positive correlation between nitrogen fertilization and ECB oviposition and larval feeding was found by many researchers [7–9]. C/N ratio is important for immobility and mineralization processes and varies with levels of nitrogen fertilization. If the C/N ratio is wider than 1:25, nitrogen would become immobile. However, if the ratio is narrower, the mineralization is possible. Plants alone are complex systems in which a lot of factors interact; therefore, we should elucidate damage potential of ECB in changing environments and techniques that will enable better and sustainable protection of plants against this pest.
